An Inconvenient Truth About The Energy Performance of Geothermal Heat Pumps

By Trish Holder

My home is heated and cooled with a geothermal heat pump – also known as a ground source heat pump.  I was sold on the idea of geothermal heating and cooling for the same reasons that I suspect most homeowners are:

  • The promise of lower energy costs
  • The attractive renewable energy tax credits, which make it easier to come to terms with the rather exorbitant cost
  • The belief that this is truly a more environmentally responsible choice since geothermal heat pumps do not rely on combustible fuel
  • The “cool factor” associated with owning a geothermal system (This was not a major driver for me, but I do get a warm glow when people are impressed that I have a highly regarded technology in my home.)

I now question (and with good reason) the validity of the first and most significant incentive for purchasing a geothermal heat pump:  Lower energy costs.

Energy Performance Not What I’d Hoped

The fact is, the utility costs in my all-electric, Energy Star, LEED-certified, geothermal heated and cooled home is not drastically better than my neighbor’s homes with far less expensive heating and cooling systems.  Now, the reasons for that are probably quite complex and have to do with numerous application and lifestyle matters that can make or break the efficiency of any type of heating and cooling system.

But none of those matters came up in that first, fateful meeting with the geothermal distributor.  No – that conversation was filled a lot of confusing yet highly persuasive information about why I should choose geothermal, including an estimate that projected a lifetime savings to me of nearly $40K!

Suffice to say the distributor offered a pretty compelling case for geothermal.  You may wonder if, after 4 years of living in my home, I find I’m on track for that type of savings.

I’d be lying if I said I thought I was.

The truth is, I suspect there was much in that conversation that would be terribly, terribly misleading to the average homeowner.  A building scientist might have called the distributor out on a lot of those details.  But neither I, nor most homeowners, go into these decisions with that level of expertise.

I open about this not because I am disappointed or disillusioned with geothermal technology.   Rather, I am disappointed and disillusioned with how the industry conducts itself, and I am concerned with the fallout to well-meaning homeowners.  Many homeowners will never see the true the advantages of geothermal energy because of misapplications.

Disadvantages of Geothermal Energy Reside in the Industry, Not the Technology

I got a hard dose of reality after the first cooling season in my home.  My system needed to be replaced because the original system was oversized—grossly oversized.  I went to a lot of trouble to confirm this fact and basically had to go through a six-month arm wrestling match to make those who were responsible bear the expense of the replacement.  I eventually won – but not before I got this depressing peek at the dark side of the geothermal/residential HVAC industry.

Were my experiences unusual?  I doubt it, especially after reading this article recently posted on, which confirmed much of what I already suspected.  Here’s is the gist:

  • The high cost of geothermal systems is not necessarily attributable to the cost associated with installing the ground loop (that is digging or drilling the holes or trenches that make it possible to transfer heat to and from the earth for the purpose of heating and cooling your home).  Over the last few decades, it is the cost of equipment, not the drilling, that has skyrocketed, making geothermal cost-prohibitive to most homeowners.
  • The cost-savings frequently touted by geothermal manufacturers are generally unrealistic and inflated, partially due to the nuances of how efficiency ratings are calculated.  One expert compared these ratings to scoring the fuel efficiency of car based on the car’s performance while coasting down a hill.  Sure, the savings estimates are based on mathematical data, but data that isn’t necessarily relevant to real life.
  • Manufacturers are more interested in selling more and bigger equipment than they are in the energy performance of your home.  This inherent conflict of interest undercuts the homeowner’s chances of getting the best bang for their buck when installing a geothermal system.  There are many factors that impact the efficiency of a geothermal system but the manufacturer and/or the installer is typically concerned with just two things:  (1) selling the equipment and (2) avoiding callbacks.  Neither of these have much (if anything) to do with actual energy performance.


Here’s the funny part.  I am still a fan of geothermal technology, as are many of the experts intent on “calling out” the industry for its…. shall we say….imperfections.

The best homeowners can do is be aware.  That’s why I implore you to read this article on  If you are considering geothermal you owe it to yourself to get the “big picture” before you dig into your pockets with your fingers crossed.


153 Responses »

  1. Thanks for the honest assessment of your GSHP system. Those of us who have gone against the grain and built way-beyond-code efficient houses sometimes take it on the chin financially. But if we share what we’ve learned (mistakes and all), we’re making it possible for lots more people to make the *right* decisions.

    The goal is to get everyone to build or retrofit green, and while we pioneers don’t always get the biggest payback, we get the honor (and good karma!) of bringing super-efficient construction into the mainstream.

    • Thanks for the comment, Andrea. It’s not always easy to be so transparent. It hurts one’s pride. :o) But you are right in that if we share “mistakes and all” we are helping ultimately helping the green building industry. And as I said, it’s not the technology, but the frequently poor execution in homes that undermines the potential efficiency.

      • My question is my home is currently heated by propane forced hot air and the cost this year was $5800 and while the geothermal solution is expensive it would seem I would start to see a return on investment after only a few years. Would you agree?

        • Bob, I replaced a propane system almost 3 years ago with a closed-loop, vertical WaterFurnace system and am very happy with the results. To measure the results, I have tracked the exact usage of electricity for both my heating and a/c since the system was installed (using a monitoring device on the HVAC circuits).

          The most difficult part of making the decision (for me) was the ability to accurately know what savings could be expected. The truth seems to be that there is no way to exactly know what the savings will be. This varies on the installer (pick someone with experience and good references), the geology below your house, etc. After monitoring for almost three years, my results were almost exactly what the predicted savings would be from the WaterFurnace website. I am not in any way tied to the industry or pushing their product. A family friend had even better results with a Climate Master system in a 4,000 sf historic house.

          Since the cost of propane and electricity varies, I will first give my results in terms of energy quantities used. I was using (on average) 1600 gallons of propane per year for heat. I am now using (on average per year) 9,800 kwh for heat and 1,400 kwh for A/C (see more on A/C below).

          At my electric cost (approx 15 cents per kwh), my cost of heat for one year is now $1,480 and my cost of a/c for the year is $220. For the first year of usage my utilities cost IN TOTAL (heat, a/c, h/w, other electric) dropped from $6,500 to $3,200. I estimate my savings for a three year period at $11,200. The actual savings are greater since I now set our thermostat to the most comfortable settings possible (69 in the winter, 72 in the summer). Previously, we kept the house colder in the winter and warmer in the summer to save money. During the summer months my electric bill was $300 to $400 per month additional for a/c. My cost of a/c now is about $40 to $75 per month (with the thermostat at 72). That was a bonus that I didn’t originally consider, I originally was focused on the obscene cost of propane (and the wild fluctuations in price).

          My house is 14 years old, 2900 square feet, center hall colonial in NJ. The insulation is average for when the house was built and described (when tested with a blower door test) as good. Our retrofit from propane to Geo involved only minor improvement in the insulation.

          The system installed is two vertical 350 foot wells – closed loop. It cost $37,000 total. We received $5,000 from the state and a $10,000 tax credit on our federal taxes. The net cost was $22,000. We have already saved half the cost and have a new HVAC system with 7 more years parts and labor guarantee. With the decrease in our utility costs, I would like to believe it increased the value of the house, but there are no guarantees. The maintenance cost of the system has been about $100 per year for new air filters every 3 months. With the wildly fluctuating cost of propane, I am thrilled with having the geo system installed and strongly recommend it as better alternative than propane.

          I did this primarily to save money and I would not describe myself as an environmentalist. That said, it can’t hurt to pollute less and I think it benefits us all if we are one step closer to energy independence as a country. Considering that the ground loop will last for generations (the well driller estimated 100 years), the long term energy savings for my house alone is truly significant. As an engineer and taxpayer, I find this a far better investment in energy savings than the investments in solar.

          As a final note, I chose a closed loop system primarily to keep maintenance at a minimum. I also understand an open loop is cheaper to install, but the ongoing energy costs would be greater since you are lifting the water rather than just pushing it through a continuous sealed loop. It also seems obvious to me, that it would have less environmental impact. I chose a vertical system because I didn’t want to tear up my lawn. I also have a gut hunch that I trust the even recovery of the surrounding earth temperatures in a vertical system as opposed to a horizontal, but I admit I may be wrong. Before installing a horizontal system, I would want to see long term studies of actual installations.

          Good luck and I hope this helps.

          • Kevin,

            You’re comment is way better then this opinionated article that provided no proof in the “Inconvenient Truth About The Energy Performance of Geothermal Heat Pumps”. The author had a lot of words he wrote with no clear example of his pain, other than to say he initially bought an over-sized system.

            I am looking to move from a heating oil / baseboard system to a high efficiency forced air system. Natural gas is not available and Propane is very expensive these days. I am looking at GeoThermal and trying to understand the operating cost. Your comment clearly outlined your experience in your specific house when you moved from propane to Geo…

            I just wanted to say thank you for your comment. You’re comment should be written as an article and published as it was very helpful for me. I’ve been having a had time finding real world information on geo thermal systems…

          • Kevin, your post is very helpful. Mind telling me the size of your house ? The sq-ft and bungalow or 2 storey etc ? I live in Ontario, Canada, have geothermal and started hating it. This is primarily due to very high hydro prices in Ontario vs very low natural gas prices these days. Effectively our hydro prices are 20 cents/kwh.

            Your statistics are very helpful, if I know the size of your house, can draw some comparisons. I already started thinking about switching to Natural Gas, possibly unheard of till date :).

          • We are currently contemplating the geothermal system in our new house. We have always liked our propane and the “hot” heat it provides. You could get up in the morning, turn on the heat, and 5 minutes later you were warm. Do you feel like you get the same effect?

          • We are considering this because of a problem I don’t see mentioned. Our house is a two story, but from the front it looks like a ranch. The lot has slope, and the lower level is entire above ground. No celler. It is an apartment.

            All the while we have lived here, our electric/oil bills have been staggering. We blamed it on a 16′ cathedral ceiling.

            Not so. The apartment has electric baseboard heat, which my mother swore she never had to use except once in a while to “take off the chill.” She has now moved upstairs with me, and my son moved in downstairs. It is summer, and he is freezing to death. Our thermostat readings are incomprehensible. Set at 75, shows room temperature of 78, and the air conditioner never shuts off unless we physically just turn it off.

            Winter isn’t as much of a problem. Since my son moved in and stopped using the baseboard electric heat, my bill has dropped by $150 to $200/month. My oil bill is only about $700 per year, depending on the year. We have a heat pump with oil backup, which is a stupid setup for PA as far as i am concerned.

            My son wants to look into geothermal. Does anybody out there have an opinion on whether that type system would even out the heat in the house? Obviously the people put in the apartment themselves. There are heat vents down there, but it just isn’t working. I’m afraid we won’t be able to sell the house when the time comes with this goofy situation. sorry to be so long.

        • My electric bill is somewhere btw $500-$800 a month on a 4000 sq foot home with geo thermal. So the least amount I spend is $6000 a yr

          • Hi there,
            I’m a former geo installer, now do geo only service work, and can’t believe all the sad stories…
            I’ve installed almost every brand since 1998, almost never had a compressor failure and have a long list of clients who brag about their low electric bills.
            The brand of heat pump you choose is almost irrelevant, it’s the design and installation that matters. Geo is physics 101, get the physics right and it works every single time.
            Do the due diligence on your potential contractor, call his references and ask if you can see their mechanical room. If you’re going to spend this much money, do the appropriate homework. The savings are all there and true, IF done right. All sorts of opportunists moved in when geo became popular and now we see the results. If you are planning a system, at least have an expert review your proposals or quotes. You should get at least 3 quotes and have a 3rd party review them and consult with during installation too.

        • Hi! I can only speak of what I know as a typical homeowner. We had geo installed in 2008 into a brick ranch in NE Ohio. We originally had hot water heat, therefore no ductwork. So, we knew up front the cost would be considerably more having to install the ductwork. Now our perticular house doesn’t have much insulation, only what we have been able to install over the years during remodels. It was built in 1959 and at that time Celotex and braick, according to everyone was all the insulation anyone would need or want. Wrong!! In the winter it was freezing and summers, the brick would heat up and stay heated, producing temps around 98 degrees even at midnight. Installing central air would be costly due to no ductwork. So weighing the cost, we decided on geo. Because of the lack of ductwork our cost for geo was around $23000.00. I weighed the pros and cons of the cost, figured out what my electric bill/fuel oil bill would compare to geo/electric. Prior to installation our combined fuel oil and electric was running around 350 (budgeted) for fuel oil, then play catchup in the Spring for several hundred dollars, and 220-325 for electric, monthly. And we were cold in the winter and died of heat in the summer! So that totals to 570-675 each month! That’s a lot. Now with geo, our monthly bill for electric runs 170-190 in the summer and in the winter it is 190-220, higher amount occurring around the holidays. We are now warm in the winter and I can have it as cool in the summer as I want!! We love it!! Now, it is a different kind of heat, if you are expecting to feel the toasty warm heat coming out of your registers, forget it!! I am amazed how the air coming from them can feel cool, yet heat the house up so warm!! And one degree can make an extreme difference in the feel! I would NEVER go back to conventional heating/cooling. The one thing I will tell you though is we are now in the process of finding a whole house dehumidifier since we are developing mildew/mold on the ceiling. Again no big deal, we find, we install! Simple as that! I love our geo!! I hope I didn’t ramble on too much—I just always have so much to say!

    • My question is are you comparing a home heated with lb or natural gas? You might be right if you look at natural gas price and your electric rate.

    • Thank you very, very much.

      • I’ve had my Geothermal vertical closed loop system for about 4 years now. Living in South Eastern, PA.

        Since then, I have.

        Re-insulated almost my entire house
        Replaced all the windows with energy star windows
        Replaced exterior doors with energy star doors.

        At the moment with temperatures in the single digits and teens. The system is struggling to keep the house at 69 while not going in to AUX heat. (AUX heat is what kills your electric bill) My electric bill in the winter is $500 – $800.

        I am considering installing a pricey propane Gas insert into the fireplace in order to help out during the winter.

        Non-heating months, the geo unit fares much better with my electric bill somewhere around $200 ish.

        • Your heating (electric) bill is $500-$800 in the winter? That’s super high.

          I live in Pittsburgh, PA. We have a 2000 Sq FT, 1960′s all brick veneer house, with older R12-R20 insulation in the walls, which are plaster veneer over drywall. Attic is R30-R45. Windows are vinyl, dual pane, gas filled, probably 10 years old.
          Forced-air Gas furnace with efficiency of 91%.

          January’s gas bill was $160. This includes a gas stove, gas water heat, and gas dryer. January was no picnic in terms of temperatures here.

          Our electric bill averages $100 fall, winter, & spring to about $160 during the summer, this with a 20 year old AC Unit, with a SEER of 13 (or is it 10?). So, total heating cost for the winter for us is probabaly around $200 month including gas heat and electric to spin the fan.

          I just don’t understand what the point of putting in a geothermal system is, if it is hideously expensive, and costs more to run than a forced air efficient gas furnace.

          • If you don’t have gas in your area you can’t have a forced air gas furnace. We had one in Maryland and paid less than half per month than what we are paying with this geothermal on the same square footage. I’d love to have gas heat again – warm and affordable.
            So disappointed in the geothermal.

          • Geothermal, when installed properly, will heat a home at a cost comparable to a natural gas system. Yes it is usually twice the initial installation cost of a comparable natural gas system but if you don’t have access to natural gas than it is a good option. If you have access to natural gas than geothermal systems usually do not make financial sense. The biggest problem with geothermal systems are companies that do not properly size and install the ground loop and heat pump, not the technology itself. My only advice is to research the company before you choose and contact their references.

        • First winter with geothermal, having replaced old heating oil system. While the jury is still out on cost savings (weren’t expecting to see savings for a few years anyway), I have to say I’m very disappointed with the performance of the system in our home, at least during this colder-than-average winter. We have had very few days when the auxiliary heat has not been on full-time.

          Even with the auxiliary heat, the far side of the house is so cold as to be uninhabitable. We had them come back and put in a separate zone (to the tune of several thousand dollars), and it’s still too cold to spend time in. Unfortunately, our laundry room is in that half of the house, and the hose/pipes freeze, rendering the washing machine useless without two or three space heaters in the room to thaw the unit before use. So not only are we using electricity like crazy, we have a situation that is, frankly, not very safe.

          I feel like either (a) the system they put in is too small, or (b) converting an older home (50-plus years old) to geothermal, even if you’re converting from heating oil, doesn’t make sense without a complete retrofit of the home’s insulation, doors, windows, etc. If we had spent the money to do that instead of geothermal, we’d have a comfortable house and lower energy bills to boot.

          Anyone else in mid-Atlantic to NE US area having the same experience?

          • Most inefficiencies in ground-loop geothermal systems are caused by poor installation of the ground coils and inferior ground coil materials. Unfortunately, the industry is not regulated and there are a lot of big money (hydro, oil, gas, government) that have a vested interest in having this technology gain a bad reputation.
            Unfortunately, it usually costs more to replace a ground coil than it did to originally install it so don’t expect any installer to admit to a ground coil problem. Best to pay an independent to verify its thermal transfer and backpressure. Easy tests and shouldn’t be that expensive.
            The main problem on installation, aside from not sinking it down far enough, is that they just lay thin plastic pipe down then crush it by piling the dirt they dug out on top of it. Thin plastic pipe with scoops of dirt weighing hundred of pounds dropped on it doesn’t stay round for long and often gets squashed. Your poor pump assumed you had round pipe, not squashed ones. This uses a lot of power on the pumps.
            As well, there is air entrapped when you put big lumps of dirt in. Air is an insulator. Ground coils need soil contact, moisture and proper depth to get to efficient levels. Properly done, GBHP systems do save 75% of heating and cooling bills. Improperly done, some don’t even work as well as a conventional system.
            There are even problems with vertical closed loop systems but usually less. Here, some contractors fill the drill hole with regular sand rather than silica/grout mixture. Saves them a thousand or two but costs you much, much more as you lose thermal efficiency. Also running the pipes back to the house too shallow and losing a lot of that wonderful free heat you just got.
            Sorry to say, the technology works like a charm but many installations don’t.
            Just for info, the first 10 ft of depth is influenced by storage of air and solar energy. True geothermal doesn’t occur until you are below 10 feet. However, the technology still works at 7-8 ft depths.
            Hope that was helpful.

          • Maybe your unit is too big. Just a thought.

            We have hydrothermal, closed loop, Florida Heat Pump brand, (30 yrs old!) for our lower floor, as well as part of the upper floor. We also have a currently non functional Trane Unit that is supposed to augment the 2 full baths, 2 halls, and two BRs upstairs, plus total of bonus room. The cooling on the first floor is great! The heat doesn’t really get it, but is good enough to live with here in NC. Right now we are trying to decide whether to replace the Trane with another conventional heat pump. We are leaning toward the conventional unit, but are having a hard time finding a qualified dealer for hydro. We want to find out if we could use the same source(350′ well plus underground loop of @ 300′) for a second system. Would apreciate it if anyone knew a truly qualified contractor within @ 50 mi. radius of Wake Forest NC. If I’m going to have a fool tell me something or do something for me, I might as well do it myself!

          • We live in Cleveland and have a 2200 square foot home built in 1929. Previous owner installed geo. Like others who have posted, the furnace seems enemic with aux heat kicking on constantly. Stinks but at least we weren’t the ones foolish enough to install the unit

          • I’ve had a geo system for about 7 years now in my current house, and have had zero issues. This is my third home that I have installed a geo system, all without any issues. My average electric bill, for the entire year, is about $93 per month, that is for hot water, all electric use, and heating and cooling. It is a 60 year old split level home, insulated to a setting of 11 on the Spinal Tap dial.

            The first month that I was in this house, without making any changes to the insulation, windows, siding, etc, I used an entire 275 gallons of heating oil, in just one month.

            Any HVAC system will not be able to work properly without the proper insulation, and that insulation must be properly installed.

            From many, many houses that I have looked at over the years, it seems that a majority of people who install fiberglass batt insulation believe that it only needs to be placed in the walls, and it will work as it should. Most of the installs have gaps in between the wall studs and the insulation. Fiberglass batts must be a snug fit in the entire wall cavity, and snug fit to everything in that cavity, electrical boxes, etc. So many installers simply compress the insulation behind an electrical box, instead of cutting around it for a snug fit, creating gaps on all sides of the box. Just haphazardly placing insulation is hardly better than not having any insulation. Air movement is the big issue. My house originally had some wall insulation, but it didn’t fill the entire cavity, and air freely moved in the gaps, negating any value the insulation added. I sealed all holes, added the proper insulation levels where needed, and now my house is just extremely comfortable.

            I have assisted friends and family, and have looked at probably hundreds of homes over the years, and I can’t recall even one that had properly installed, or proper levels, of insulation. EVERY attic that I have ever looked into, you could see the ceiling drywall below through gaps, or light fixtures that you could see the light from the room below in the dark attic, or dust around holes from the walls, a clear indication that air was freely moving between the rooms below, through receptacles, through the holes that the electrical wires go through, just so many issues, that it is hard to believe that so many home owners probably pay a contractor to do this work, without ever checking the work.

            Don’t blame the HVAC system when it may be your insulation that is the culprit. Air movement is your biggest enemy.

            The numbers simply work for supporting a geothermal install. If you don’t have the properly installed insulation, you are wasting your money, regardless of the system you install.

        • Harmon pellet stove

        • We had a similar experience. Our home is 2,500 sq ft, new construction with good insulation in Southern CT. We opted for a geothermal for 48,000 by the time it was all done. It worked reasonably well in the first year, electric bill went up about $250 a month in the winter months. But after the first winter, the system couldn’t keep the house warm at all. It kept failing for a number of reasons and finally we had someone other than the installer look at it. The heat exchanger was installed in reverse and the ground loop was leaking. $7,000 later we barely got through another winter and finally opted to install a regular heat pump. Since then, we’ve been reasonably ok, though we need space heaters when the temps drop into the teens. Worst decision we’ve ever made.

          Problem was the installation and absolute lack of support. There is only one installer for this kind of system in our state, and that guy went to a 4-day course and became a certified installer for that franchise. People who opt for geothermal are at risk to be taken to the cleaners by a hack due to lack of training and oversight. Never again.

    • Hi I have a geothermal furnace. A letter from Hydro One states I use 116% more hydro then my neibors! Great paid thousands upon thousands for a hydro sucker! So angry, now what? Take it out? Absorb the lost $.

      • Is your geothermal run on city water (metered water you pay for) ??? It should be run from a well on your property.

      • Bonnie
        Just deciding which system to install. I live in the Goderich area debating between a geothermal,propane or oil. Since you live in Ontario and hydro costs are rising would you recommend a geo thermal system?

      • Hi Bonnie,
        I’m feeling like a sucker, with Hydro Ottawa, just got it installed… and the date it was turned on in late November the usage sky-rocketed. The home is about 2200 sq ft, and in the fall I had a $50 monthly hydro bill and a $60 hydro bill (warm autumn). Late November-December was worse, it went up to $407, and I got a bill Friday for Dec-Jan for $897. So I’m so disappointed and upset. I don’t know if I can turn off the auxiliary heat myself to ensure it doesn’t come on (assuming that is the issue). We can insulate the house better, I’ve already caulked and put shrink wrap on the windows, and we’ll blow insulation in where we can this summer, but I feel like a complete sucker.

      • Bonnie, I noticed you mentioned Hydro One…does this mean you are in Ontario? I have had the same experience…very high hydro bills…but Hydro One never mentioned anything about me using more electricity than my neighbours, so now I am wondering whether that is the case, and whether it is due to our geothermal system. That makes me angry because one of the things the salesman promised was lower heating costs. I’d like to sue the company for false advertising!

      • I feel your pain.

        Our house came with geothermal…we didn’t install it. But we’ve been paying above and beyond our worst nightmares for it, especially here in Taxtario. The Ontario Hydro rates make Geothermal utterly unrealistic. The system cannot even keep up at moderate winter temperatures…I swear the system stays “on” for hours at a time, failing to raise the temp of our main floor even one degree.

        We will be talking to our neighbours about collaborating to get the Natural Gas run down our end of the road. Natural Gas will be far cheaper than this hydro-eating white elephant in our basement.

        I’d like to know why the biggest Geo provider in Ontario, NextEnergy, went out of business. Could it be because geothermal is just not realistic, especially in Ontario? The guy that ran NextEnergy was one of the biggest evangelists for geo…and now the company is just dead and gone.

      • Oh and by the way, we’ve gotten the same letter from Hydro One. it’s an incredibly stupid letter given that our “neighbours” are all mennonite farmers who largely use wood heat (which actually works, unlike the geothermal).

    • No offense, but I live in a tiny 10 x 20 cabin. My heating bill is $8 a week and that includes cooking when the temperature drops to the teens and below. I live in Upstate New York where we get -34 and below at times. I have solar taking care of everything else. And I only use my gas generator for back up (last year that meant only using 1/2 of the gas in my 5 gallon container being more than usual). All I’m saying is people used to laugh at me and now they don’t. By the way, with last year’s horrible winter, I still only spent about an extra $8 a month and I was walking around in shorts and a t-shirt shirt inside, while keeping the temperature at around 75.

    • Look guys True Geothermal ….real Geothermal, your only going to find in areas with active Hot springs. If you want real Geo. move. Anywhere else is a joke and a wast of money. Your only going to pick up a limited amount of heat from the ground and make up the rest of the heat you need to feel comfortable with the standard mechanical compression action of a heat pump..and that uses electricity! Lots of it !

      Think of it this way. your standard heat pump pulls heat from the outside air. Great if you live in Florida and the outside temperature never really gets cold in the winter months, but in the northeastern states…Forget it ! Conversely a Geothermal system pulls heat from the ground…that’s great if you live near a hot spring or volcanic earth where ground temperatures are into the hundreds of degrees and no additional mechanical heat action has to be applied for your home to reach comfort.

      A good example of Real Geo is found in Iceland where hot springs work great to pull heat from ! Google it, do the research, learn some basic thermodynamic laws, and make good informed decisions.

    • I can look at Geothermal from a totally different angle. We have a brick ranch built in 1959, so, in that day insulation wasn’t used, at least on ours because the builder claimed brick and Celotex were all the insulation needed. We also have plastered walls. We were facing a new furnace and installing central air in the attic, since we didn’t have heat ducts due to the fact that we had hot water heat that ran through copper pipes to the registers. No cold air returns were used. So, since no duct work it would have cost a ton to install for the central air. We were facing thousands of dollars to install the heat and air. After spending $2400+ for fuel oil over the winter and a minimum of $230 per month for electric, not to mention no central air in the summer and let me tell you a brick ranch without insulation really heats up in the summer, the decision was a no brainer. We were lucky to have found an awesome contractor who was honest and trustworthy. We had the heating and cooling installed along we duct work for the main floor and the whole basement, approximately 2400 sq ft. I will be totally honest, yes it was costly because of the duct work. Our bills have changed exponentially along with the temperature in our house. We no longer need to keep the thermostat at 70 daytime and 64 nights, freezing continually. Nor do we have to swelter in the heat of the summer when our lovely brick ranch would heat up to a stifling 96+ degrees and would never cool off at night. We lived in this house for 30 years dealing with this problem before changing over to Geothermal. I mentioned above what our expenses were per month, approximately $575 to $650 for electric and fuel oil and usually had to pay catch up on the fuel oil bill. Our bills are now one bill for electric, and at the very most it has been $315 and that was over the holidays with all the baking I do.
      We are thrilled beyond thrilled that we now can have Geothermal, which we’ve had since 2008, long enough to know if it is good or bad.
      So my take on it is this, get referrals, others who have Geo in your area can be the best way to find out information , along with who should do the installation. As I said, we were lucky in our choices. Our whole installation and equipment was half of Trish’s! And we needed duct work installed!
      I will tell you that the heat feels differently from forced air, you don’t get that warm blast of heat from the registers. Our Geo is a contstant heat, you really can’t ‘feel’ the warm air coming out of the registers, but, the rooms are now an even heat, no cold spots. And the air, oh my, I am thrilled to have air conditioning. No more melting every evening all summer long.
      I think the answer to Trish’s problems stem more from the contractor than from the actual GeoThermal. These days, you can never have too many referrals, word of mouth is the best way to save money. For example, we need a new roof so I contacted one gentleman who quoted verbally anywhere from $15000-$20000. We knew automatically that was rediculous. We checked reviews and everyone we met we asked and now will have a new roof with shingles removed, all the bells and windows done for only $8000. And I have seen this contractor’s work first hand. So it pays to do your homework upfront. That is the key.
      I feel badly for Trish and here experience and can see why she is disenchanted. Sorry she didn’t have our contractor do the work!

      • Sorry I misread Trish’s note, thinking she paid $40,000 for her unit, instead she was told $40000 for lifetime savings. That sounds like a far stretch to me, but, then again her contractor wasn’t upfront on a lot of information.

        • Pam,

          I wonder if some of the result of your lowered heating costs were due to the fact that you upgraded your ductwork. In other words, your home sounds like it suffered from an inefficient (if not nearly ineffective) airflow design – no system can be effective without proper airflow.

          • Barbara,
            Our ductwork which we had for our previous hot water heating system consisted of copper pipe which ran through the whole house into each room connecting to a register, and heated through a hot water boiler. I would imagine similar to the way the old radiators worked. So I guess you could say, we ‘upgraded’ our ductwork.

    • The author of this article Trish sounds like she might be the kind of person who is hard to please. First hints…complaining about her system being grossly oversized, then insisting that someone else pay for it. Hint Trish: do some research. Its not that hard to determine what size unit you need. Why didn’t you get more than one opinion before installing an oversized system? Whose fault is that? If it was undersized, you can bet you would have complained about that too.

      You also fail to provide ANY details…just generalizations. How much oversized? What was your power bill before and after? Sounds like you have an axe to grind, or you’d provide some specifics.

  2. Nice post! Some really good writing, cuts right to the issue of incentive.

    NMEB is the disconnect. Not My Energy Bill. No accountability or incentive to drive the clients energy bill down.

    Here’s something from Wisconsin on gshp:

    Uncertainty of installation is another issue. I really like air source, the technology has really advanced, much less uncertainty.

  3. I completely retro-fitted a 1939 brick ranch house in Beverly Hills, Michigan (outside of Detroit)

    1725 square feet before we added 775 sqft in a second story.

    We blew in cellulose (recycled paper) insulation in all the walls, old and new.

    When we were finished, the total energy cost for the home, including the hot tub, was around $2400 a year.

    You can’t just install the HVAC and expect return. You have to take the house on as a system, and ensure you have all factors right.

    This article gives geothermal a bad name, largely, I suspect, due to the owner’s failure to address insulation (or he used fiberglas, thinking that it is insulation. It’s not. It’s better than nothing, but not by much).

    His failure to do proper and thorough research is his fault, not the vendor’s.

    • Whoa Pete! You would be waaay wrong about that! My house is insulated with a hybrid system of closed-cell SPF insulation and blown cellulose, micro-caulking, super efficient windows (argon-filled), California Corners, CFL lighting, all Energy Star appliances, etc. etc. etc. As I said in the article, my house is not only Energy Star rated with an impressive HERS, it is also LEED Silver certified. Short of going to school and becoming building scientist AND a mechanical contractor myself, I’m not sure what else I could have done to ensure an energy efficient home.

      • Trish,

        Whether you have certifications or equipment is not what makes the structure more efficient. It sounds like you did allot of homework and are continuing to do so. kudos for you for being engaged and willing to tell your story.

        I contend that this project you took on that is also your home has given you experience that no building science class can give.

        Interesting and well written.Thank you for sharing

      • Hello Greenspiration,

        Was wondering if you could provide a little more information.
        Do you know how many kwh your GEO heating / cooling /system pulls annually? Are you able to separate your space heating / cooling consumption from your base load consumption?
        Do you know the heat / cool loads on the house? Your HERS documentation should provide that. What is the size of your GSHP? Standing column, bore hole or ground loop.
        Is your GSHP running on electric strip mode for some reason and do you have controls that tell you when it is running on electric strip? Usually the TSTAT will say it’s running in emergency stage or 3rd stage (assuming it’s a multi stage)
        Does your GSHP generate any DHW?

        I can tell you from rating / working on over 200 GEO homes that a properly sized, well installed system can run very low electric bills for many homeowners in truly excellent building shells. Is the heat pump and ductwork in insulated space / basement?

        Yes, there are definitely clunkers out there that will never perform well, but a GEO install contractor that 1) actually knows how a system should be designed and commissioned and 2) does truly care about his business reputation, will be able to install a system that pays off your capitol investment.

        If your contractor can’t or doesn’t want to help you find out what’s wrong, Call his competition and consider recommissioning the system. If the competition is an experienced GEO tech, he should be able to help you.

        • Kevin,

          This was all several years ago, and as I say in the article, it took about 6 months to get the manufacturer to send another contractor out who did confirm the system was oversized and he replaced it with a smaller unit.

          I do not have all of the metering you mention, but I would like to at some point. It’s on a very lengthy list of “to dos”. Like I said in the article, I do not blame the equipment for the inefficiencies. The equipment does what it does. And I am well aware that the unit is but one part of a system (loop design, ductwork, envelope, controls, and even thermostatic control). The contractor (who was also the manufacturer’s territory manager — a no-no) was certainly at fault.

          As I said, this has since been resolved, although getting it done was like pulling teeth. Everyone wanted to blame someone else for the screw-up. Luckily, I had some crucial documentation to prove culpability.

          • Trish,
            I totally agree with your assessment. Too often contractors want to install and run. Give the “tailight warranty” instead of true customer service. We take on a 2 year warranty on all our labor for all our installs. We also give 1 year maintenance with all the installs so that we are maintaining the system as it should be and teaching the home owner. I believe a contractor must be willing to be “married” to each project to be the “go to” expert with any issues. The HVAC industry is supposed to solve indoor comfort issues, not just sell a box.
            The bottom line is..the contractor should have been giving you great customer service and working with you to find a solution, not passing the buck.

          • Rick,

            I love the idea of a 1 year maintenance and I hope that your homeowners take advantage of that one-on-one time. When you give a homeowner knowledge you empower them — and it shows that you respect them. I so wish all HVAC contractors did this. And for all you homeowners out there who think this involves an extra expense or can’t be worth it, I strongly, strongly disagree. Experience the service, expertise, and respect of a good contractor and you will gladly pay extra for it in the future.

  4. The key element for losing efficiency in your story is what happens with many HVAC systems whatever their type, OVERSIZING. Fix the whole house if you can, size HVAC accordingly, install it correctly, test it, be more comfortable, save energy and money and get refferal business from a satisied energy saving customer.

  5. I commend your honesty and willingness to share your real experience with geo thermal. We picked up the message somewhere that ‘bigger is better’ and ‘how can you have too much of a good thing?’ Many people want others to think they never make mistakes and as a result contribute nothing to advance social conciousness. Truth is, we learn more from our failures than we do from our successes. Your story will directly benefit me in the near future. Cheers!

  6. There is still much we do not know about this case: where is the house and its climate zone; the size, number of bedrooms and occupants; the pattern of use, especially at peak demand times when utilities might ramp up charges; separation of house loads from plug loads; any peculiarities of the site that might be causing problems.

    A Manual J calculation, part of LEED for Homes requirements should have given the right sizes for HVAC components.

    Suggest getting an independent commissioning agent (not part of designers or contractors) to review the whole house systems and verify that they are working as intended.

    • What vexes me about this, and what nobody has mentioned yet, is the energy star requirement to not oversize equipment. 15% oversize is all that is allowed in the new version, not sure of what year version your home went through, but since this was a 2013 article I assume 2012. Anything after 2012 should have hit that 15% maximum allowed requirement and I believe that was still a requirement of the old v2 energy star as well.

      Your hers rater should have cought that when you hvac guy submitted his manual Js etc…. but sometimes that waits until a project is completed because the hvac guys never actually did them in the beginning…..

      What this also comes down to is watts per sq ft. It is hard to attribute higher than normal energy use without some kind of miles per gallon sticker. Passivehouse makes this the basis of their standard:

      “The building must be designed to have an annual heating and cooling demand as calculated with the Passivhaus Planning Package of not more than 15 kWh/m² per year (4746 btu/ft² per year) in heating and 15 kWh/m² per year cooling energy OR to be designed with a peak heat load of 10W/m²”

      Our last LEED house was about 2300 sq feet, HERS of 50% better than code so no crazy amounts of insulation or anything, and about $1100 a year in total energy bills which exactly matched out energy modeling calcs. They also had some solar thermal that brought the water heating down a bit, but I would expect geothermal to be slightly better than this. If it is not then something is obviously wrong. $90 a month for a 2300sq ft house is pretty legit without having to go geo. They just had a good forced air heat pump.

      Thats about 4.34kw per sq ft per year. Passive standard would be 4746btu/sq ft per year. That is 1.39kw. Insanely low and achievable only with massive amounts of insulation.

    • “The fact is, the utility costs in my all-electric, Energy Star, LEED-certified, geothermal heated and cooled home is not drastically better than my neighbor’s homes with far less expensive heating and cooling systems. Now, the reasons for that are probably quite complex and have to do with numerous application and lifestyle matters that can make or break the efficiency of any type of heating and cooling system.”

      When you draw a conclusion simultaneously admitting you have no data from whence it came it’s kinda of lousy to suggest ignorance, wrong doing or poor business practice of others.

      A comment like yours above reminds me of someone who rates gas milage of their car by where the needle is pointing with complete disregard to tank size or miles driven.

      Sizing is an area of debate in the industry, particularly in heating dominated climates. Some think auxiliary heat is bad while others think a little auxiliary heat goes a long way in first cost savings adding a few dollars to the annual bill but saving thousands on the system cost. Oversizing rarely adds a significant amount to annual operating cost and may reduce it (unless other factors are present such as undersized duct system) but can if it is literally 2 to 3 tons oversized.

      “Inconvenient Truth About……” your title and conclusion is that you don’t even know if it is accurate or not. That’s not very “Greenspirational”.

      For others, when shopping for geothermal (like anything) find the best dealer and the rest will take care of itself.

      • I agree. When I read the lines:

        Suffice to say the distributor offered a pretty compelling case for geothermal. You may wonder if, after 4 years of living in my home, I find I’m on track for that type of savings.

        I’d be lying if I said I thought I was.

        You mean you don’t know?

        After this there was no way to read the rest of the article with an open mind.
        And what about the old adage, “if it sounds too good to be true, it probably is”.

        My own estimate is about a $250 savings per year. $40K in a lifetime?
        That sounds fishy already. Especially since the lifetime of the units are rated
        at about 25 years.

        It is amazing that the author did not do calculations with previous bills in her own home instead of simply comparing bills after the fact. Then going on an emotional rant about something of which she admittedly has no specific details about.

        On of my neighbors has 3″ of Polyurethane spray foam insulation on the roof, and insulated concrete siding which looks exactly like wood. The rarely if ever have to heat or cool their home. They also have strategically placed trees as an added benefit.

        I could just as easily compare my current energy bills in my not yet “greenified” home to theirs go on a rant.

        • Shane, I have to disagree. For me, it’s very clear that Trish is right and the contractor is wrong.

          All the client needs to know how much the project costs and how much the energy bill will drop. And of course the break even period.
          It doesn’t matter how complex the required calculations are. That’s the job of the contractor.

          • Tony,
            “All the client needs to know how much the project costs and how much the energy bill will drop. And of course the break even period.”

            Really? Do you take everything a salesperson says at face value? The client (“shopper”) should know some of the geo installers previous customers and success stories in applications like theirs. The client could learn very easily from a google search that if Nat gas is available or electric rates are high geo may not be a good fit in their home or that even with a carefully designed system the payback horizon is much further away.
            The client could stumble on some geo forums where many pros offer advice about systems they may purchase.

            If you had a friend who bout a 1 ton pick up truck because the salesman said it would pay for itself in 5 years with fuel savings over his 6 cylinder van, you would likely not blame the salesman when the predictions didn’t come true. You’d ask your friend why they didn’t do a modicom of research and if that’s true, then you do hold people accountable for knowing more (and seeking it on their own) than how much it will cost and save…..

    • So many knowledgeable responses here! I am impressed!
      Maybe someone can give me an approximate on what a whole house dehumidifier would cost for an approximately 2400 sq ft ranch in zone 6, with a GeoThermal heating system already installed!

  7. Trish, It is beyond words how disappointing that your experience has been. When you take on a home project, you want it to be fun and rewarding as well. Rewarding as in finacially sound decisions as well as pride in a job well done. I can say first hand that geothermal has been very efficient at my fathers homes in Iowa. When he first spoke to me about the heating system selection process I was sticker shocked by geothermal. Having gone to school with the contractor,I was cofortable with his decision to get it. His bills are so low it is unbelievable. I had to see the bills themselves. He was very proud. My parents have their home,in my opinion,too cold in the summer and too warm in the winter. The science never let you down. It was something else. I hope you can get it corrected and have something to be proud of.

  8. Excellent post Trish, and great conversations. I would like to add that while I heartily agree that a whole house approach is necessary to get results, I believe that there are fundamental issues with ground source heat pumps as residential HVAC systems and the way they are marketed. I base this on research I did while on the staff at the Vermont Energy Investment Corporation several years ago with my colleague Bret Hamilton.

    In the best possible case, installing a GSHP as opposed to a conventional HVAC system is trading a larger upfront cost for long-term savings. We found that whether or not that is a good trade was very dependent on the local climate and the price of electricity vs. alternative heating fuels. In short, if you lived in a heating dominated climate with relatively expensive electricity and access to natural gas it was hard to make the numbers work given the typical cost of a GSHP installation. In a hotter climate with cheaper electricity GSHP looks better.

    Unfortunately, the “best possible case” is not the norm. The energy performance and installation cost of a GSHP is really sensitive to the skill of the installer, as is the installation cost. If you get an experienced installer and a site with no complications it can turn out well. If you are working with someone who only does GSHP infrequently, and you have interesting soil or groundwater things can get expensive or performance may be poor.

    The big problem is that all of this gets glossed over in industry promotion and there is a history of support from electric utilities more interested in selling electricity than in saving their customers money. I wish that the GSHP industry would provide 1. broad research on actual costs and savings from residential GSHP installations, and 2. a savings guarantee with each new system. This might reduce the number of GSHPs going into the wrong places, and force the kind of attention to cost and quality that the industry seems to need.

    • “I wish that the GSHP industry would provide 1. broad research on actual costs and savings from residential GSHP installations, and 2. a savings guarantee with each new system.”

      That WOULD be great wouldn’t it, Chris. It will, of course, never happen and for some pretty obvious reasons.

      • Trish, thanks for bringing this subject into the open. I appreciate hearing of your experience and of the many postings either pro or con GSHP.

        It is my understanding that ESCOs frequently amortize efficiency projects for commercial and industrial projects so that the payments come directly from utility cost reductions. Should a homeowner require a similar payment plan following the ROI sales pitch, imagine how quickly GSHP manufacturers, distributors, and contractors would run for the door.

        I also read the reference article (and responses). There was discussion as to whether $42k or $24k was a more pertinent average for a residential system. I have spoken with a woman who reported converting her upstate NY 1500 sq. ft. summer home to a year ’round residence with GSHP and radiant floors. She claimed to have spent $70k on the “heating system”. Let’s hope that she got at least some sealing, high grade insulation, and ceramic tile floors for that price. Otherwise, we might think that local contractors reached into the deep pockets of a relocating NYC professional.

        • That does sound high — but then again if she included the radiant in with that, maybe not so much depending on what she had to deal with there. I’m really not familiar with pricing on radiant floors. Sure would like to have radiant though — especially in my master bath in the winter!

          • IN upstate NY, I have seen radiant cost more than $50K, without geo. However, radiant is the most expensive heating system, and in a high performance home does not even save money. In high performance home, the floors are rarely warm due to the low loads. Although they are not cold.

        • Let’s see: Average annual utility cost in cold climates is $2-$3,000 per year depending on fuel costs, with about a third of that for demand loads. Assume that the heating load is reduced 50% by the new system. What is the simple payback period? 70 years? or 24-25 years for just the GSHP!
          I’d say, start with a ballpark estimate. If the numbers look possible, then proceed with closer analysis. Otherwise, stick with insulation.

  9. With all the interest in GSHP this is a great exchange. We do HERS, Energy Star testing as well as Green Build verification and have seen a real uptick in GSHP installs in new as well as retro situations. I had a GSHP installed in a new home that I had built in 1985 and was thrilled to death but not before several issues were worked out. I live in climate zone 5 so we have more heating days than cooling and the first three months were winter months with the electric back up running most of the time and not being able to get more than a 70 degree register temp with the heat pump running. Air in the loop ended up to be the problem with register temps going to 110 degrees and 0 back up needed. As indicated lifestyle/rates/system layout is very important but so are elements outside of these. Three years ago we were called to a home that we had done a rating on in the fall of the year with GSHP with a very high electric bill. After a physical inspection with a thermal camera we found a few voids in the insulation where trades installing ceiling speakers but no “open window”. What we did find was a instant hot water system that was installed to have on demand hot water to three baths and a kitchen Nice feature but nobody thought to insulate the copper hot water pipes. The system was putting constant demand on the electric hot water heater above what the GSHP could provide by radiation thru the copper since the circulation was constant. The fix? Unplug the instant hot water system. Problem solved. The sales pitch may be over the top but the home as a “system” must be considered.

    • I have a geothermal unit for about 15 years and this is what I have learned.

      Energy usage: set the unit up on off peak energy metering, meaning the power company can turn it off during very cold weather. Your back up system should be a separate natural / LP gas forced air furnace Do NOT use the electric coils.
      This installation gives you several advantages. Warm gas heat when you want it, half price electric rate with the off peak metering. Two separate systems with two separate t-stats so no interlocking issues. Run the geo. System when you are not at home and gas when at home, set your gas t-stat 10 degrees or so below the geo just in case the geo doesn’t keep up.

      These systems work OK for heating and very good for cooling. Keep in mind that you remove the heat from the ground in the winter and recharge (add heat ) the ground in the summer.

  10. In full disclosure mode, I am a Certified GeoExchange Designer and geothermal/solar integrated systems contractor in Colorado and Texas for the past 12 years. I have an MBA, Masters in Architecture and Bachelor’s Degree in Aeronautical Engineering (thermodynamics). I was a RESNET rater and have Advanced Building Science Masters Certification.

    While I found your article interesting, and clearly an indictment on the industry as a whole — especially where non-certified HVAC companies are installing ground source heat pumps (GHPs), the headline should read “The Contractor Who Installed My First Geothermal Heat Pump Sucked.”

    Your experience and byline is more accurate – “Disadvantages of Geothermal Energy Reside in the Industry, Not the Technology.” Ironically, this is true of the HVAC industry in general. In full disclosure, please amend your posting to include your interest – “I am a writer and marketing consultant for the Heating Ventilating and Air Conditioning (HVAC) and construction industries. That’s what I’ve been doing for the last 14+ years.” Xcel Energy did an audit last year of their certified air conditioning contractors (NATE certified and Xcel trained and certified). Only 50% got the ASHRAE Manual J loads correct and most improperly sized ductwork and equipment. Like your experience, all of the customers that had oversized SEER 20 air conditioners installed suffered with poor performance. This is not an indictment on the technology, but on the industry.

    As an HVAC consultant, have you consulted for GHP companies or only convential heating and cooling? If the latter, the article loses merit.

    As the owner of a low energy home and ground source heat pumps (, I have tracked actual energy consumption against the software modeling provided by the GHP manufacturers. While I agree that the utility bill savings are not as predicted (as the estimates to not include non-related demand fees/tariffs), the energy use in kWh is accurate. We fully disclose simple payback and ROI for a variety of renewable energy technologies on our website. However, a more accurate metric is the internal rate of return (what payback do I get for investing in geo versus CDs, gold, solar PV, the stock market, etc.?)

    You will find as I have in dozens of installations that the IRR on geothermal versus propane is over 20%, and compared to natural gas prices in Colorado is over 10%. This IRR is more favorable against any HVAC technology or renewable alternative with the exception of upgrading insulation and air sealing.

    A final note. You live in North Carolina. Joe Lstiburek, Building Science Corp, once commented on the ten top mistakes that clients make. Buried in the list as this, “If you live in the South, don’t let a Yankee design your home.” The point is that the performance of GHPs is North Carolina is not representative to the other 12 climate zones/subzones in the United States. You can use air source heat pumps. These are not a viable option in Colorado. You can build a house to the PassivHaus standard (similar climate zone to Germany) and heat it with a light bulb. We can’t do that in Colorado. Your first contractor sucked. Well, yes we have a lot of those in Colorado.

    Engaging in dialogues like this will inform consumers what they need to look for when researching sustainable heating and cooling options. The first criteria – a trusted contractor who follows industry best practices when installing equipment. The second – a list of recent references that the contractor provides (six minimum) for similar projects (technical, size, and scope of work). Third – competitive pricing in a detailed quote by line item for all components in the system, including a validated energy model of the savings with the assumptions (such as building loads). When that is achieved, the actual tecnology that is implemented is mute. Solar PV panels make a statement to your neighbors. GHPs quietly save you money that would otherwise be sucked out of your bank account and sent to your utility. Along the way, someone up North might notice over ten years the ice is melting slower.

    Thank you for engaging this forum. I appreciate your insights.
    Al Wallace

    • So glad you asked that question, Al!!!! My writing communications services are focused in commercial HVAC, not residential. Nor do I currently have any advertisers who sell or make heat pumps of any kind-not that I would turn any advertisers away. Greenspiration Home is an initiative to educate homeowners. Getting clients or pleasing clients is not what this blog is about. And this particular entry is an absolutely true account of what happened to me (and validated by the findings from another article/study which are referenced in the blog.)

      I think other homeowners will benefit from knowing my experience whether they choose geothermal or not — especially if the choose geothermal.

      • With all due respect siting another bloggers opinion is not exactly factual validation. I have critiqued Martin Holidays writing on geo several times because I find it based on limited information and I know from my experience as a GSHP designer that both his and your conclusions are just plain wrong. If you only take a sample of the bad in any industry you will get negatively skuwed results. The fact is properly installed GSHPs are the most efficient way to heat and cool a home.

        • Jamie–Let’s not forget that the above blog references Martin Holladay’s article which references a VERY REPUTABLE study by Steve Kavanaugh, a professor of mechanical engineering at the University of Alabama and a nationally recognized expert on GSHPs. Holladay quotes Kavanaugh as saying: “I believe that the GSHP industry has created a deceptive rating system to counter the deceptive air-source heat pump rating system. I feel it really hurts the industry, as it promises unrealistic energy efficiency numbers when, in fact, they are less efficient units that what the ratings suggest.”

          You can discredit me as a simple “blogger” (albeit one who has worked and written in the HVAC industry for 20 years now) and you can try to discredit Holladay as well (although that’s REAL stretch) but I think Kavanaugh’s critiques of the industry carry quite a bit of weight — admittedly far more than mine.

          Finally, I can assure you my experience was factual. I’ve also been exposed to enough information (from HVAC professionals of all kinds and well as homeowners) to know that my experiences are far from unusual.

          • Trish,
            You are missing the point. Your article is an indictment of geothermal heat pumps, my point is geo is no more subject to the problems you have had than any other type of HVAC. So if you want to write an article about the issues across all HVAC systems I’m with you but to hold geo out as the loan offender is just inaccurate. To your point about Steve Kavanaugh his quote mentions the deceptive rating system in both air-source and geo so it really supports my point that both you and Holiday would be better off taking aim at the entire industry rather than focusing geo systems. Again I feel you are quite clear in your article you had a contractor problem and no it is not unique but the technology is solid as long as it is installed correctly. This next part may sound mean but if you have been writing about building science for 20 years and you let an HVAC contractor oversize your system then shame on you, you above all should know better.
            I seriously do not mean to be adversarial here I just get frustrated when people single geo out when writing articles like yours. I can assure you none of my customers have experienced the problems you described.

          • Jamie–You may have missed in the comments (see below) that it was the manufacturer who was the contractor. He wasn’t supposed to be wearing both hats, but he was, and I’m sure his own manager was well aware of this. So, it was the manufacturer who was advising me to install a much too large system. I came to the conclusion that the manufacturer would know the capability of their equipment better than anyone else. Who could blame me for that? Heck — an Energy Star rater took the same position! So I let them install the system they wanted. Shame on me? No. Shame on the manufacturer territory rep and everyone else at the company who was fully aware that he was acting as the manufacturer rep while performing work under his own contractor’s license. And shame on him for not performing an accurate Manual J.

            Not once in this article to I blame the equipment, so I’m not sure how you reach the conclusion that the article is an indictment of geothermal heat pumps. I say twice that that I am a fan of the technology. If there has been any indictment of geothermal heat pumps (or the use of them) I might argue that it is the industry that has indicted itself.

    • Al you are my hero! You just saved me 30 minutes of typing a response to this misinformed article. She has a contractor problem and is blaming the industry as a whole. Thanks for the great response.

  11. It sounds like you took a lot of time researching building components to build your house but then decided, as many homeowners do, to go with the cheapest quote on an installed system. I don’t like to jump to assumptions and say that is what you did so now I’ll ask the question to confirm. Did you go with the least expensive bid? Cheaper isn’t always better. We’ve been installing Geothermal for over 40 years and the systems work great. There are factors to consider before moving to geothermal. The building shell and how tight it may be is the first factor. If the home is leaky and has very little insulation the HVAC equipment is the last item to worry about. I come across numerous customers where the system has been oversized because the installing contractor didn’t understand the building assembly or used old rules of thumb for sizing. I to am a homeowner and look to get the best bang for my dollar but I also do a lot of research before dropping that kind of money with any contractor. The Tax credit has been not only an incentive for homeowners to purchase geothermal it has also been an incentive for contractors to start installing these. Unfortunately some of those contractors don’t have the experience to deliver upon those promises. I see the problem not being the geothermal system but the company who installed it. I guess I should be thankful for some of those companies because it does create work for us in the future when we do get the call to correct what was done incorrectly.

    • John,

      Least expensive bid? No. I was more interested in getting a good installation — ironically. I was in contact with the manufacturer from the very beginning, which led me down the ladder to the territory manager. He recommended a family member’s contracting firm — indicating that I would get him in the mix to keep an eye on the job. What he didn’t tell me was that the family member was not licensed and it was actually the territory manager’s contracting license that the family member was working under. Oh–but there were business cards, company name, the whole nine yards. Regional manager was aware also — he knew the installer. Somehow it never came up in all our numerous conversations. Territory manager visited the jobsite ONCE — before construction even began. But he stayed in touch, mostly to advocate the 4 ton system the installer wanted to put in. As I say in the blog, we’ve since replaced the system with a 3 ton system. We have plenty of capacity. And yes, a Manual J was done, but as I’m sure you know, a Manual J is only as accurate as the numbers that are entered, and if a contractor is determined to put in a certain size system, then those numbers can be manipulated.

      • Trish,
        I hope you reported these individuals. There is nothing that frustrates me more or for that matter that gives reputable HVAC contractors a black eye then people like this performing this work. We do a tremendous amount of training, not that a piece of paper with our names on it makes us qualified, to ensure that we offer our customers the best possible product at the most reasonable price. I’m sorry to hear that you got caught up in someone’s selfish desire to turn a quick dollar. You couldn’t be more correct about the manual J inputs. I can’t begin to tell you how many times I’ve come across those with some seriously flawed data. I wish you all the best with your new system.

  12. Trish/others –
    It is true that there are many variables involved in achieving a top performing geo system.
    As one commenter mentioned – Where is this project? How many heating hours annually? How many cooling hours? Load?, etc.
    Here in the northeast where we have alot of heating hours and a high electric rate a properly installed geo system delivers DRAMATIC savings.
    However, competent installers often find themselves under-designing systems to meet or beat the lowest bidder.

    Most common problems
    a.) Undersizing the earth coupling capacity. Yes it is expensive, but if you do not follow ISO-13256 design exchange temps (because you decided to undersize the loop or well to reduce first cost of that piece), your heat exchange will NEVER serve the heat pump what it needs to perform as AHRI/ISO confirmed in there system test.
    b.) Using electric resistance heat as a second or third stage. Augmenting a COP of between 4 and 6 with a COP of 1 is like eating salad all week, and having a tub of ice cream every weekend. Anyone purposefully designing a geo to regularly use electric resistance is really missing everything geo stands for.

    It is true, that there is nothing in it for the installer or builder, so they tend to deliver the lowest priced system. Not the best performing system. Look at the last generation retrofit a/c market. Long crimped flex duct runs, oversized condensers. Back in the 80′s and 90′s no one said they wanted the most efficient installation… they all wanted the least expensive installation. That is what is happening with geo now, and it is true, the manufacturers are NOT working to endorse ISO/AHRI installs. They are focused on selling boxes this quarter.

    In fact, as geo designer/distributors for over 38 yrs. we get challenged all the time re: our “no compromise” approach to design by our installer customers and there homeowners and builders in an effort to reduce first cost.
    While we will NOT yield to departure from ISO/AHRI designs WE publish, we ARE always interested in ways to minimize first cost as long as ISO-13256 is maintained.
    Unplug the resistance heater, don’t squeeze off your air flow (this may be what is causing your coil freeze ups), check your incoming earth fluid temps (different for open and closed system types) during summer and winter design conditions to be sure you are not outside AHRI/ISO exchange parameters and you will probably find your problem.

    The science is proven and the published SYSTEM efficiencies are 100% attainable when the install is done properly.

    To all the under-designers, short – loopers and electric resistance guys out there that are understandbly challenged by the “close enough” marketplace realities – This communication thread is clear evidence that Geo will not proliferate if we don’t stick to ISO – 13256 application protocols.

    • Hi Martin,

      You sound very knowledgeable indeed and I want my readers to get the full benefit of what you have to say. Some (not all) hvac contractors will be able to follow what you say, but few if any homeowners will. Can you translate this down in a way that informs and helps the homeowner?

      • Trish,
        I applaude your efforts to keep this dialogue focused on the homeowner and their needs. These are my takeaways from Martin’s post. though I will add a different perspective from Europe on the idea of using electric resistive heat strips.

        1. One third the price of geo heat pump (GHP) is the cost of the ground loop used to exchange heat with house – sending heat to the ground when cooling, and taking heat from the ground when cooling. THIS IS THE MOST CRITICAL COMPONENT of a ground source heat pump system, and the party most incorrectly installed in residences.

        This loop is called a ground heat exchanger (GHEX) and can be vertical well holes, a horizontal trench, or tubing in a pond. There is no water actually exchanged with ground water as these are closed loops as you have with a radiator in your car. Using manufacturer’s recommendations, a GHEX operates within a temperature range providing the best price/performance for the heat pump efficiency. The manufacturer is required to comply with a temperature range of incoming water to the heat pump in order to meet the efficiencies they advertise (in the U.S., this is an ARI or AHRI standard, in Europe this is an ISO standard). If the GHEX is too large, it is slighty more efficient but the first cost is prohibitive. If too small, the GHP is not efficient because it is using hot ground water when it is in cooling mode, and very cold water in heating mode — since the GHEX gets hot or cold quickly. A contractor can adjust these temperature ranges from manufacturer recommendations (say from 35 to 80 degrees) within the sizing software if their intention is to save money by letting the GHP operate at more extreme ranges (such as 20 degree to 100 degrees). I personally use the manufacturer recommendations and do not use the standard as my benchmark: similar to building codes, they represent the minimum performance not optimum performance. While a GHP may be designed to operate in extreme ranges, the goal is efficient operation at moderate ranges. Every major GHP manufacturer provides their dealers with a software program that is used to size the GHEX based on soil type and moisture content against the exact model GHP that is proposed. The GHEX sizing defaults to the manufacturer recommendations. A contractor can game the system by inserting soil types and moisture content that undersizes the ground loop, so follow these best practices:

        BEST PRACTICE – 1) Homeowners should ask for a printout of these calculations, and obtain similar reports from several geo contractors. If there is a great disparity in equipment or GHEX sizing, the homeowners should request an explanation. 2) The homeowner should also insist that the contractor is certified for GHEX installation by the International Ground Source Heat Pump Association (IGSHPA), and 3) The homeowner should ask for recent references (6 minimum) for GHP installations very similar to that proposed.

        2. Manufacturers offer the low cost option ($500-$800) to additional heating capability to the heat pump. This is called electrical auxiliary strip heating and consists of heating coils inside the exhaust duct of the GHP, similar to the heat elements in your toaster. The purpose is to provide emergency heating to your home if something happens to your ground heat exchanger pumping, and to supplement the heating output of the heat pump. Air source heat pumps (ASHP) utilize strip heat for all of the heating when the outside air temperature is too cold to effectively heat the house (less than 40 degrees).. The efficiency of electric strip heating by definition is 100% (Coefficent of Performance at COP of 1.0 = kilowatts out divided by kilowatts in). An ASHP efficiency is usually around 200% (COP 2.0). A GHP efficiency ranges from 350% to 500% (COP =3.5 to 5.0). When using strip heat only, an ASHP and GHP operate at 100% efficiency.

        Mario clearly believes from posting above, that the GHP GHEX should be sized for the peak heating/cooling load of the home. Unlike furnaces that have separately sized air conditioners, GHPs provide about the same output in heating as cooling. While all competent contractors agree the GHP should be sized to meet 100% of the peak cooling load, there is much debate in the industry about the heating sizing. It is critically important that homeowners do not take a stand on GHP sizing based on any one post here as much is dependent on the climate zone. Where I live in Colorado, the peak heating load is 60% of the peak cooling load. In Phoenix, the reverse is true. In Phoenix, the GHP must be sized for the cooling load making it oversized for the heating load. In Colorado, I can size it for the heating load and it is oversized in cooling. Or with strip heat, I can size it for the cooling load and make up the difference using strip heat … or somewhere in between to optimize the first cost with the cost of operation (less efficient using strip heat).

        In Switzerland, 99% of the homes utilize GHPs though most are in floor heating with hydronic coils (versus forced air heating used in the U.S.) The reason for the high percentage of GHP installations is that all equipment and ground loops are provided free by the utility company, and then the consumer pays for the BTUs that are used. Given the choice of any type of system, the utility companies invest in geothermal becasue it has the highest efficiency. However, the utility company must balance the first cost of the GHEX with the overall system efficiency. They found through research of actual installations, that the ideal tradeoff (for their specific climate zone) is a GHP that is sized for 85% of the PEAK heating load (highest demand at the coldest design conditions are usually warmer than the coldest possible outside temperature.)


        In Colorado, when I run the analysis using this metric sizinng for 85% of the peak load, the GHP meets 97-98% of the annual heating load (all BTUs used). The same program that provides GHEX sizing, also provides this information — amount of heat in kWh required by the heat pump and the amount of electric strip heat to augment. Again in Colorado for an average home (2500-3000 SF), the strip heat amounts to 2-3% of total BTUs at a cost ranging from $60 to $100 per year. When considering that the first cost of GHEX to meet all of the demand is an additional $3,000 to $5,000, it does not make sound financial sense for two reasons. 1) a consumer will never see a satisfactory return of $5-8 month for a first cost investment of $3,000, and 2) the increased cost of operation for a larger heat pump designed for worst case outside air temperature is not justified for 2-3% of the operating hours. I would rather have a 3 ton heat pump running 97% time and use strip heat when needed, than operate a 4 ton heat pump year round (at 33% higher energy consumption at peak load). I explain to my homeowners that this is like commuting to work in a Prius and renting a truck when you need to haul something big, versus driving a truck as a matter of routine.

        Finally, and before I get jumped on by my colleagues, understand that heat pumps we install are two stage heat pumps with variable speed high efficiency fans. A two stage heat pumps is like have a car with a turbocharger. It runs at 65-70% of the total output most of the time, turning on the second stage when demand requires. This is the same reason I do not size the GHP to the full heating capacity when our peak cooling load is 60% of that capacity. If in cooling mode, the heat pump can only operate at 65% of the total heating capacity making it oversized in cooling. By sizing it smaller, the heat pump has some capabilities at running less than full capacity of cooling. Using my example above, a 3 ton heat pump can operate as low as 1.8 tons in cooling to peak load in cooling at 3 tons. This represents real world conditions as our cooling load only hits peak 1/4th of run time, so I am only using second stage cooling when required.

        Al Wallace

    • Trish:
      This article with more than enough posts to point those with GHP’S, not performing correctly, those considering replacing existing system with GHP’S or considering for new construction.


      Is your GSHP running on electric strip mode for some reason and do you have controls that tell you when it is running on electric strip? Usually the TSTAT will say it’s running in emergency stage or 3rd stage (assuming it’s a multi stage)
      Does your GSHP generate any DHW?

      Unplug the resistance heater, don’t squeeze off your air flow (this may be what is causing your coil freeze ups), check your incoming earth fluid temps (different for open and closed system types) during summer and winter design conditions to be sure you are not outside AHRI/ISO exchange parameters and you will probably find your problem.

      Undersizing the earth coupling capacity. Yes it is expensive, but if you do not follow ISO-13256 design exchange temps (because you decided to undersize the loop or well to reduce first cost of that piece), your heat exchange will NEVER serve the heat pump what it needs to perform as AHRI/ISO confirmed in there system test.

      Using electric resistance heat as a second or third stage. Augmenting a COP of between 4 and 6 with a COP of 1 is like eating salad all week, and having a tub of ice cream every weekend. Anyone purposefully designing a geo to regularly use electric resistance is really missing everything geo stands for.

      My comment:
      ISO – 13256 application protocols must be followed and the homeowner should become vary familiar with it.
      Since the system relies on three systems, the Heat Pump, Earth coupling capacity and interior Supply / Return / Ducts and of course insulation and sealing each must work in conjunction.

      Would you install a septic system without performing the required tests, perc and mantle test?

      If ground water or soil charastics play a part in the GPH”S performance it seems a geologic report should be done.

      A great article and more than enough info to keep all out of trouble.

  13. After reading this article I cannot help but remember the old Latin phrase “Caveat Emptor” or let the “buyer beware”. It is unfortunate that this geoexchange system is not performing to your expectations, not only for yourself but for the industry at large. There are many instances when the customers expectations are not very realistic for a multitude of reasons, however, I don’t feel that this is the case in this particular instance. Based upon your comments, my perception is that you performed the neccessary exercises of due diligence and have done your homework from a technical perspective. So why is this happening to you? I am a firm believer in the geoexchange / Ground Source Heat Pump (GSHP) technology however, that does not automatically translate into an individual or company’s ability to effectivley implement that technology. I suspect that the issue of the substandard performance of your geoexchange system falls within one or more of the following areas; 1.) The required system desgin calculations were not sufficiently completed. 2.) An error occured within the calculations 3.) The installation of the system did not meet the design specifications. I don’t like to make assumptions however based upon what I read in the article, this is my initial reaction.

    While the actual idea of geoexchange is an old one, the frequency in which these systems are implemented is far less than a more traditional HVAC system design. As such, I think the opportunity for “error” during the installation phase is substantially higher, unless the contractor specializes in geoexchange systems, then it needs to be assumed that there was some cost cutting involved which is a no-no! Case in point!

  14. I think the answer lies in the ductwork. Go to Trish’s blog post, “Dirty little secrets about your homes ductwork” and blog post “What I did for LEED”. Look at the pictures and you will see the problem. The HVAC contractor installed a “standard” duct system for this area, which consist of seriously long flex duct runs that have kinks and are above the insulation, but go in in hours rather than days.

    For far too long, and continuing today, the HVAC contractor hears, “This is too expensive, you have to get the price down to get the job.” so often that he just designs for the lowest cost and does this because it is the “standard” and no one wants to pay more. Why waste his time trying?

    I tell people I am the most expensive when they call and ask for a quote. A third hang up and this is good since they never would be my customer because they are shopping for the cheapest contractor. The other 2/3 ask “How can you say this?” Which lets me get into best practice and why my duct systems are more expensive, but a better value.” Those who really listen become my customers, and I have to deliver.

    Unless you find a “nut” like me, or know how to get a great duct system, high performance geothermal systems will not be high performance.

    More attic insulation is also in order. Double would be about right, more cellulose is cheap once the crew is there anyway and you can get the contractor to do the extra for 1/2 normal price and he will still make money.

    Ductwork should be inside conditioned space.

  15. A ground-source heat pump (GSHP) based system needs to be well integrated with the building and the distribution system. Making these systems operate optimally requires an understanding of a lot more than the pieces of equipment that are bought. Some contractors may not yet adequately understand how to optimize system performance.

    It can often be useful to have a knowledgeable but disinterested third party to help homeowners understand their options across technologies before choosing the contractor. An energy advisor/systems specialist can be helpful to the client in discussing the attributes, benefits, and costs of various system approaches
    and help teh clinet choose the technology and the contractor best suited to help them.

    For a client desiring both heating and cooling A well-considered and designed system including GSHP or modern air-source heat pumps can perform very well and be be a very efficient system. GSHP does entail higher first costs, however.

  16. It is worth the money to call in a building performance consultant to evaluate and test your home for energy efficiency. They can advise you with the data that is collected on the best, most cost effective route to achieve your energy efficient goal. They will also give you a better unbias view of all the options available and the pro’s and con’s of geothermal vs. radiant cooling/heat vs. high performance HVAC. It is also possible the your current system could be plenty efficient and it is other factors in the home that are making the system in-efficient.

    Either way it is best to have a professional come in and test your whole house as a system.

    • A building performance consultant? As in a HERS rater or Green Rater. We had two of one and one of another. I would say I have a less biased biased view of geothermal than most green building advocates. I’m sorry I can’t report a more favorable experience. We tried our best to do everything right; everything by the book. And yet this experience was disappointing on many levels. As I say TWICE in the article, I am still a fan of the technology. It is the industry that troubles me. And clearly (by the articles I site) there are industry experts who share my views.

  17. As someone who has installed over 150 geothermal systems, I found the title of your blog very provocative. But, after reading through, I can definitely understand where you’re coming from and you have good reason to be unimpressed.

    Your situation is just another example of a bad design and installation that frustrates those of us who are advocates for geothermal. It’s especially frustrating because bad installations undoubtedly get more press time than the good ones and put a stain on the entire industry. I’m so sorry that you fall into the bad design and installation category.

    I hope you’ll keep writing about your experience and let us know what has been done to fix your geothermal system. It’s difficult to know where exactly things went wrong based on the information you have provided. I know I would be interested in seeing a resolution and seeing you write another post entitled “Geothermal Saved me Tons of $$$”!

    • Melanie,

      Thank you so much for your comment. It seems comments are divided squarely between people who are down on geothermal and those who are down on ME for sharing my story. I believe transparency is important for the green building industry. It hurts my pride as much as anyone else’s to say that this was a disappointing experience. As for “fixing” my system, I suspect entirely reworking our ductwork and adding more insulation (even though we spent a not-so-small fortune on insulation!) are probably the minimum we would have to do to getting the most out of our system. Which begs the question, would I have been better off to invest in a top of the line, all sheet metal duct system, designed by a building performance expert, and throwing in additional insulation and investing about 10K less in the heating/cooling system? I can’t say for sure that I have the answer, but I know how I’d bet if I had to bet….

      • I am very curious about which part of the system was oversized. Most problems I hear about in the Northeast are due to undersizing. Do you mean the groundloop, the heat pump, pumps, the ductwork or all of the above? It is unclear to me how adding insulation would help with an oversized geo system.

        Would you be willing to share more information?

        • Melanie — It was the geothermal heat pump that was oversized. You can read a little more about that here: And I think you may have understood some of the comments about insulation. Several people have pointed out that in order to maximize the efficiency of a geothermal system (or any system for that matter) you must have a tight envelope. I don’t think anyone intended to say insulation was an solution to an oversized problem. In fact, it would probably make it worse!

      • Wow! This is a great set of posts.

        In the post above, it is not a fair comparison. Almost anything done right is better than done wrong. I am disappointed you had the experience you did. But it appears you had a bad contractor and this just happened to be the geo company.

        As a home builder, we have taken over geo and conventional hvac installations in-house because we found even certified geo contractors did not do the job right. I think the most common problem is ductwork installations, which is a well-known common problem with conventional hvac installs. The second problem is having an understanding of the “big picture,” or the house as a system.

        In my home, in upstate ny, my geo system costs me a fraction of what it would cost to heat with propane. Much less than my last home and my neighbors home, both EnergyStar and built by me, on propane. And those homes have half the heated area.

        So at the end of the day, geo makes a lot of sense for many of us in heating climates, but it has to be done right. I think that your question in the last post might could be rephrased something like this:

        “If we had put in a conventional system at a much lower cost installed wrong too, would we feel better because we spent so much less?”

        It’s a shame this happened to you, but it’s all about the installation and design, not the technology.

        I hope you succeed in getting it corrected and encourage you to contact the manufacturer and your local licensing board.

  18. It is so sad that your builder allowed an HVAC dealer to do a poor design and installation. When geothermal is done correctly it DOES provide the benefits you and many others desire. Please understand that manufacturers of the geothermal heat pumps don’t do the design or installation of the systems. You can find poor quaility contractors in all fields. I can see your frustrations but a LEED home should have shown this as an oversized system before you took ownership.

    If you still have issues I will provide assistance for you. I work in this industry & I HATE to have peole put statements / articles like this out that send people away from a great technology. Please contact me if you need assistance.

    Reagrds, Richard

    • Richard — The manufacturer WAS the contractor! My original contact was always with the manufacturer. The regional sales manager pointed me toward the territory manager, who I originally met with. He recommended a family member for the job — saying I would get him (the manufacturer territory manager) in the mix. What he failed to tell me was that HE was the contracting license holder for the family member he recommended. That’s against licensing laws — I found out much later. I happened to have an email from the territory manager (from the manufacturer’s domain) urging me to put in the oversized system and suggesting that the numbers of the manual J could be manipulated to get to where they were sure I needed to be.

      Thanks — I don’t need your assistance. I fought this battle tooth and nail on my own and got the system replaced. And I will never forget what I went through while the manufacturer tried to blame everyone and everything else (from the unlicensed installer) to my ventilation fans. Finally, a very good geothermal contractor confirmed the system was oversized and after some more arm wrestling, I got the system replaced. As I said in the article, I am still “a fan of the technology.” I get that you “HATE” articles that share unfortunate stories relating to geothermal — but I HATE it when people in the industry respond to this article as though I was speaking of the technology, ignoring that I say within the article (twice) that I am a fan of the technology. Make no mistake, I was talking about the INDUSTRY and clearly, by the studies I site, there are experts in the industry who feel the same way I do. Oversized systems get installed every day by contractors that are trained by WHO? The manufacturer! Bottom line, if people want to have a successful geothermal installation (which also happens every day), they need to be aware of the potential pitfalls. It ain’t all roses and butterflies. Sorry. But it’s not.

  19. Trish
    Not to beat a dead horse here but you say over and over that your a fan of the technology and that your article was not an indictment on geo so why the provocative title ? Maybe a better title would have been “Geothermal HVAC design and install are everything !” I guess you get more responses from provocative titles and lets face it geothermal is the current punching bag of the building science blogosphere.

  20. Trish,

    We can easily get all caught up in the weeds discussing the pros & cons of geothermal heating technology, but I remember the words from a former colleague who was the VP of Quality Control at Carrier, when ever I would relay a piece of information that I felt certain was indisputable he would simply reply “…and you’re basing this position on a world wide sample of one?”. I did find it very motivating to pursue supporting opinions, but I eventually understood the real message, which is to understand fully and keep an open mind. I would like to share one experience regarding a geothermal system. After a system was designed by a Professional Engineer and installed by a competent contractor, the client walked into the mechanical room and inquired “Why is it so hot in here? (It was about 95 degrees), and the engineer explained with all the certainty in the world “Geothermal can only heat water to 52 degrees, after that you need a boiler!”. The client, very calmly explained that she had lived in Sweden for 40 years, and she had lived in many homes that were heated with geothermal and she never had a boiler….and she then fired the engineer, and hired our firm to evaluate and make a recommendation. It became clear that the only solution was to completely gut the mechanical room and start over, a decision that was not easy to make. And now after more than a year of monitoring the new system, we are providing 100% of the heating, cooling, domestic water heating, and heating a 58,000 gallon outside swimming pool without a boiler. The client is also purchasing “green electricity” from the grid, so she has successfully achieved “zero-carbon”. So, there are a couple of morals to this story…. Not all geothermal systems are alike….. and clinging to a perspective in spite of overwhelming evidence to the contrary, such as the engineer being firmly entrenched in his belief (delusion) actually can cause tremendous damage, financially to the client as well as reducing the incredible good that can be created by the widespread adoption of properly designed and installed geothermal systems. Be well!

    • John, see my response to Jen’s comment above. My reservations about the state of the residential geothermal industry are hardly based solely on my own experience. That’s not to say all projects go south — or have as many issues as mine. But there are too many.

  21. Trish,

    with interest I read you story, it sounds very familiar to me. I am a Certified Geoexchange Designer, and certified Installer in Buffalo NY.
    As I always say, geothermal can be heaven and geothermal can be hell!
    We hear similar stories from consumers all over, based on 2 scenarios. Either the contractor is new to geo, sees $$$ and thinks he can make a lot of money with it. That contractor then completely underestimates (or really does not know) what is involved to not only make those systems work, but also make them work efficiently. That contractor usually does 1 job and never touches geo again, but does not abandon the customer, and he or the customers calls us to fix it.
    The other scenario is that the contractor still does not know how to make geo work efficient, and and does not care, keeps building inefficient system, and soon or later goes out of business, as just happened in our area. Many people got hurt, I received calls from 17 customers this winter from a single black sheep installer. Shame on them (the installer).
    But part of the blame is also on the customer: The customer shops around, gets 5 quotes and takes the cheapest one, jumps ship for $200 less. That installer is usually not the best or experienced one, and he does not use the most efficient design or equipment.
    Not saying that you did that, but you did not do your homework and checked out the experience and reputation of your installer. If you need surgery, do you choose the surgeon who never did the operation, or the guy who does it 3 times a week for the last 20 years? In your case, the surgeon did not even know where to make the cut, e.g. did not even have enough skills to size the system correctly. You as a contractor should have seen the inherent issues and conflicts with the sales rep being involved in the design and construction.
    Now, to the specifics of your system: A 4 ton size versus a 3 ton size does not make a system inherently inefficient. The BTUs your house requires remains the same, and a larger heat pump delivers those BTUs with almost the same efficiency, it simply does not turn on as much due to its higher capacity. Yes, in general the COP (efficiency measure) of a 3 ton heatpump is slighly better than a 4 ton, and the larger unit turning on and off more will cost you a bit, but overall your performance due to over sizing should not be affect you more than 5-10% at the most.
    What oversizing does in heating dominated climate is reducing the comfort in cooling mode, especially in heating dominated climate, because due to the oversized capacity the thermostat gets satisfied very quickly, so the run time in not long enough to take the humidity out of the air. So it will feel cold but “wet”, and very dehumidified. But the impact on efficiency is minimal by a 4 ton instead of a 3 ton unit. If you don’t see the efficiency you should have there is something else going on with your system, again, not surprising giving the inexperience of your installer.
    Also the manufacturer is not to blame here, they deliver the boxes to you, cookie cutters, and unless there is something wrong with the box, they perform well as promised. I am not aware of a single manufacturer acting as a contractor, or territorial managers of the manufacturer acting as contractors. Please clarify who those guys are, what company?
    The rating system. Geo heatpumps are rated for heating at certain incoming ground temperatures, 41F in first stage and 32F in second stage, a temperature the ground loop reaches usually at the end of the heating season, after much of the heat is extracted out of the ground. The same is the case for cooling, 67F and 78F respectively. That means that most of the season the incoming water is warmer and the heat pumps actually perform much better than rated. The same can be said for cooling season, right now our ground temperatures for horizontal loops is around 40F (coming of the heating season), so the heatpumps perform with an EER above 40, much better than rated, and the maximum ground temperature at the end of the cooling season top out at 65F, much lower than what the heatpumps are rated at. This means that if the system is designed correctly, they perform at a higher efficiency than they are rated at, at least in our climate.
    How do I know this for sure? We monitor about 20 of our system online and stream the data live on our website.

    In other words, we proof to the customers that the systems perform the way they should. Especially energy efficient houses HERS rated house run very efficient.

    As others said here before, you blame your negative endeavor on the manufacturer, the contractor, the rating system, and geothermal system in general (according to your title), but your are not providing details and don’t allow other here to jump in and help, and allow them to pinpoint your problem with the geo system.
    There are 2 excellent forums where people can go to for help and professional installers are assisting with advise:

    They include Shoppers checklists to help people avoid problems like you have them.

    The inconvenient truth here might be that you, despite your experience in the HVAC field, did not do your homework correctly. Your story, as typical as it is, might mislead many people and paint a wrong picture of a reliable and money saving technology. I am a bit sad since I would have expected more objectivity from you in your position, and more responsibility. You used your position to vent you personal frustration. With your insistence that your story is an inconvenient truth about geothermal system you might need to consider that you damage this kind of green and renewable technology, did a lot of unwarranted harm, and painted a picture which could not be further away from the truth.

    • Thank you for your comment, Jens.

      The “inconvenient truth” about the efficiency of geothermal heat pumps, in my opinion, and as I have tried to illustrate in this article, is that which is promised is rarely delivered, because, as you say, there are many contractors out there who (for whatever reason) are not designing systems for optimum performance. Clearly, you encounter this quite often, as my story sounds quite familiar to you. That’s an important point I want homeowners to understand. A contractor can make or break a system depending on both his competence with geothermal and his integrity. No argument here.

      The question is, how easy or difficult (or impossible) is it for a homeowner to choose a good geothermal contractor? In my case (as it has come out in the comments here and my responses to them) my original contact was with the manufacturer — in fact, I first contacted the president, since I had his email. From there I was given the regional manager’s contact, who gave me the territory manager’s contact, who met with me multiple times, showed me his own home’s system, and generated a report on my estimated savings. He also recommended a contractor — a family member — saying that I would get his expertise (the territory manager’s) in the bargain. I think any reasonable homeowner would be thinking, “How could this possibly go wrong? I’ve got the territory manager riding shotgun on a contractor he personally recommended!” The territory manager remained in contact with me far into the project, urging me to accept the contractor’s advice that I needed a 4 ton system. I took his advice and ended up with a grossly oversized system. As I mentioned in a previous comment, the territory manager failed to mention that the installer he had recommended did not have his own license. In fact, he was working under the territory manager’s license. (Although that is against state licensing laws, I’m not sure this is an altogether uncommon scenario.)

      Now, the fact that it was the territory manager who urged me to install the oversized system tells me there is a problem within the industry.

      The fact that you tell me (and a ton of other industry professionals have told me) that they frequently encounter poorly designed systems, also tells me there is a problem within the industry.

      The fact that any of this could have happened to me under these circumstances tells me there is a problem in the industry.

      The fact that the industry expert I cite in the article has gone on record as saying “I believe that the GSHP industry has created a deceptive rating system to counter the deceptive air-source heat pump rating system. I feel it really hurts the industry, as it promises unrealistic energy efficiency numbers when, in fact, they are less efficient units that what the ratings suggest,” tells me there is a problem within the industry.

      The fact that I get contacted fairly frequently by people who are disappointed with their installations or people who know people who are disappointed with their installations, tells me there is a problem within the industry.

      The conversations between HERS raters, contractors, and other industry professionals that I am exposed to (and I mean almost daily) tells me there is a problem in the industry.

      The fact that I have witnessed more fingerpointing than accountability tells me there is a problem in the industry.

      Finally, the fact that I’m not sure there is any amount of homework a typical homeowner could do to totally avoid bad advice or erroneous installation, tells me there is a problem within the industry.

      Yes, we check out our doctors before letting them perform surgery. But we’re not typically given a bad recommendation by the chief of surgery. And we don’t typically have to dig into medical journals to learn the fine details of what errors might be made during surgery by how to avoid them. And Doctor’s don’t usually recommend other surgeons who don’t have medical licenses, or “share” their license with other people who want to operate too. I could go on, but I think you get the point.

      • Dear Trish,

        the problem in your case is that you did not go to the chief of surgery, you did not even go to a surgeon, you went to a business person who manages a company who supplies the instruments and tools for the surgeon. Then you were handed down to the local sales rep for the instrument company, who is not a surgeon nor is he even a doctor. Then, for some reason, you allowed this guys who has never done surgery before, to do surgery on you! Which urges the question: What were you thinking?

        Did you bother to look for people who are trained and certified to do the work?

        You also continue to insist that the over sizing is the root for your inefficiency problem. As I pointed out a 4 ton unit is not running significantly less efficient than a 3 ton unit. Actually, modern dual stage 4-ton units can modulate down to 2.5 tons and their ECM fan can reduce its blower speed. But you did not engage into that discussion, nor did you post data here for people here to see, despite numerous requests, to see what kind of load data your house requests. Also requests were made to you to post details, including information about loop performance, operational parameters, heat pump data (model, hydronic, forced air?) or even your location. So what else is going on what makes you system so inefficient? It is clearly not that a 4 ton heatpump was installed instead of a 3 ton. Unfortunately, you failed so far to provide any details about your case. So you accuse the geothermal industry here without providing any evidence.

        Unfortunately to did not post the link to our sample page where we post operational data for a bout 20 systems, here is another “neutral” link to an energy monitoring site with some example, but also data supporting the notion that system can operate even better than rated over the seasonal average,

        We display the performance of the systems on the web, putting proof behind the claim that systems perform at or beyond the rated efficiency when they are designed and installed correctly. About 80-90% of our referrals are from friends, relatives, neighbors and colleagues of former customers. Do you think they would refer people they care about to us if the systems do not fulfill their expectations.

        We have multiple builders in our area partnering with us for their building projects. They made geothermal standard in their houses, yes you have to specifically op out of it as customer. Do you think they would do so if they would not have the enthusiastic feed back from their customers?

        So I would challenge your industry expert that the rating system is flawed. Please point me to a single scientifically based study or report, where properly designed system are not performing.

        Did you know that over 90% of the new built houses in sweden use ground source heat pumps. Can an entire nation be mislead to use a technology which has all those issues you are citing?

        The only problem in the industry is that geothermal performance are complex system involving in depth knowledge about fluid dynamics, heat transfer, geology, and the efficiency of materials used including the electronic controls.

        This knowhow usually overwhelms inexperienced and untrained installers, and can leed to systems which are either not working at all, or work inefficient.

        All the other problems you site as problems in the industry are either based on your own personal dilemma (which you don’t really detail us about) or on hearsay from others.
        To pick an untrained and inexperient installer to design and install your system is like….allowing a person who is neither a surgeon or a doctor to perform surgery on you.

        • Jens,

          You sure take a lot of liberties with single analogy. Such analogous acrobatics are more suited for Cirque du Soleil than a reasonable debate. Nevertheless, I will try to responds to each of your statements.

          First, the installer of my system was factory trained. Sorry to burst your bubble. But you bring up an interesting point. IF a homeowner — say a green minded teacher or accountant — goes to a heat pump manufacturer and asks for a recommendation for a contractor, how many homeowners are going to question the manufacturer? After all, isn’t the manufacturer’s reputation on the line? How would the average homeowner even know that there was a published list of certified installers — not that that guarantees a successful installation. Clearly.

          Second, where in any of this did I ever insist that the root of my inefficiency problems were due to oversizing? For that matter, where did I even say that I knew for a fact that I had inefficiency problems? For the record, my system is no longer oversized — at least not to the degree that it once was. However, I suspected it was oversized because I could hear it cycling in short intervals with my very own ears. And I was also monitoring the humidity in the house that was staying over 60% during peak cooling season. The fact that it WAS oversized was confirmed by a certified installer.

          And, no, I will not post links to your geothermal contracting firm’s pages. If you want exposure for your business on Greenspiration Home I’m afraid you will have to pay for it just like any other sponsor. With the exception of our American Made Decor Pick-of-the-Week, we do not mention company names or website links in our blogs or in the comment section.

          Also, Mr. Kavanaugh is not “my” industry expert. I’ve never met him, but it is clear that he is a respected member of ASHRAE. I’ve ghostwritten for ASHRAE Magazine before and getting through their editorial advisory board is no cake walk.

          You challenged me to point to a single scientifically based study or report where a properly designed system is not performing. Interesting choice of words — but I’ve run into that careful phraseology before. Of course they are performing! The equipment operates exactly as it was designed to. The question is are they delivering the quality of performance that is promoted.

          I was not aware that over 90% of houses built in Sweden use ground source heat pumps, but if that is the case, perhaps the industry in Sweden is a bit more careful about who they allow to install their products. As best I can tell, it’s a little loosely goosey here. Not that there aren’t fine installers. I have had a very positive experience with my current contractor.

          I totally agree that geothermal performance has great complexities that necessitate an in-depth knowledge about fluid dynamics, heat transfer, etc. My question is, why would the manufacturers sell their equipment to incompetent installers? That just seems foolish, but clearly it happens. And sometimes (as was my own case) the installers are neither inexperienced or untrained. Just pig headed.

          The industry problems are well documented in Kavanaugh’s study. And if anyone wants more evidence that there are serious problems, eavesdrop on a few professional HVAC/RESNET linkedin groups.

          Please. This isn’t news to anyone in the industry. But it is not the kind of information consumers encounter, except for their own personal experiences. Sadly, they are the ones who are shelling out the money for these high ticket systems.

          • I wonder if you could tell me what humidity levels should be with a geothermal system that is operating correctly? I am experiencing ++ humidity my windows are virtually dripping and am wondering if it is due to something going awry with my heating system.

          • Hi Lenna,

            A comfortable healthy indoor humidity can range from 40 – 60%. Some people like it higher, some like it lower. I personally like 50 to 55%. In heating mode, virtually any forced air heating system in most US climates is going to dry out the air to the point that you’ll wish it was a little more humid. So I can’t begin to tell you why you should be having such problems. I would recommend getting a (GOOD) Hvac guy to take a look, but you could also call on someone who is more specialized in building science, like a home performance specialist or HERS rater.

  22. Right on posts! After implementing the first rule of energy efficient design: “reduce the building energy load through passive means”, it may turn out that geothermal simply is not worth the investment.

    Several points on geothermal:

    I have talked to developers who say, “look, between the state and federal rebates, so much is paid for, I would be crazy not to use geothermal”. Paid for by…your fellow taxpayers…us.

    Second: Walgreens is using geothermal in a net zero prototype. Payback with geothermal subsidies is about four years. Payback without subsidies may be over twenty years, by which time maintenance and replacement issues typically arise with geothermal. If a prototype is a model to be followed, is it a good business decision to plan on the subsidies being there years down the road?

    Third: Net zero is a worthy goal, but at what cost?

    Currently geothermal is winning awards as a tool used in conjunction with ICF’s to achieve net zero in schools. However, a geothermal/ICF system may deliver only slightly more energy efficiency than an insulated thermal mass building envelope with no geothermal.

    Insulated thermal mass (insulation exterior to thermal mass ) is recognized in the Advanced Energy Design Guides as the most energy efficient insulation configuration for mass walls in all climate zones. It can be a zero added cost alternative to the less energy efficient ICF’s.

    Consider a cost analysis of a 75k sq ft school, based on geothermal industry-supplied figures. A geothermal system costs taxpayers an additional million dollars and results in savings of about 2750 dollars per year (about 3 cents per sq ft), over an insulated thermal mass wall system.

    While geothermal is clearly slightly more energy efficient than an insulated thermal mass envelope, the cost of using the geothermal system instead of the insulated thermal mass system is not recovered until after 363 years. Consider that typical geothermal systems may require component maintenance/replacement after twenty to thirty years, so the payback time may actually exceed 363 years. That’s kind of a long time.

    Again, insulated thermal mass can replace ICF’s at no cost or cost savings, and eliminating geothermal altogether can provide upfront cost savings that may pay for more solar or other renewable sources that can bring a building to net zero efficiency with substantial cost savings. Cost savings translates into less tax money needed, and so less tax has to be collected.

    If the proponents of geothermal and ICF’s succeed in having an inefficient net-zero template emulated and implemented, the causes of energy efficiency and fiscal conservancy lose.

    Finally, no disrespect to engineers, but there is a tremendous incentive to advocate for geothermal. Each system requires site specific engineering, and many billable hours.

    Geothermal is a complex, active system, and the first rule of energy efficient design is….?

  23. Trish,
    besides my reply to your comments, I must also set the record straight.

    You stated
    “The cost-savings frequently touted by geothermal manufacturers are generally unrealistic and inflated, partially due to the nuances of how efficiency ratings are calculated. One expert compared these ratings to scoring the fuel efficiency of car based on the car’s performance while coasting down a hill. Sure, the savings estimates are based on mathematical data, but data that isn’t necessarily relevant to real life.”

    You also responded to my post
    “The fact that the industry expert I cite in the article has gone on record as saying “I believe that the GSHP industry has created a deceptive rating system to counter the deceptive air-source heat pump rating system. I feel it really hurts the industry, as it promises unrealistic energy efficiency numbers when, in fact, they are less efficient units that what the ratings suggest,” tells me there is a problem within the industry.”

    You site Martin Holladay’s article about Geothermal Heatpumps, and he states:

    “The problem dates back to 2000. On January 1, 2000, a new standard (ISO standard 13256-1) replaced two earlier standards (ARI 325 and ARI 330) used to rate the efficiency of GSHPs. Whereas the ARI standards included an allowance for the electricity used by pumps to draw well water or circulate fluid through ground loops, the new ISO standard eliminated all pumping energy from COP calculations. The effect was that COP ratings jumped up: for the same piece of equipment, the COP rating under the new ISO standard was higher than the COP rating under the old ARI standards.
    For consumers, the advantage of the old ARI method was that it at least made a stab at including pump and fan energy — unlike the current ISO method, which simply abandons any attempt to account for these essential energy inputs.”

    The performance standard AHRI/ASHRAE/ISO 13256-1 became effective January 1, 2000 and replaces ARI Standards 320, 325, and 330. This new standard has three major categories: Water Loop (comparable to ARI 320), Ground Water (ARI 325), and Ground Loop (ARI 330). Although these standards (ARI and ISO) are similar there are some differences.

    So a study was conducted by the National Institute of Standards and Technology with a grant from the Department of Energy to test the same equipment via those 2 different standards. Equipment was tested with and without air ducts installed. ISO cooling energy efficiency ratio (EER) with and without ductwork units were 4.5% higher and 3.9 % lower than the ARI, respectively. ISO heating coefficient of performance (COP) for the ducted units were 6.2 % higher and for the unducted units 1.0 % lower than the ARI, respectively. Meaning that the new rating improved the efficiency rating by 4.5% in heating and 3.9% in cooling for ducted heatpumps. In unducted systems, the newer rating system actually penalized heatpumps by 1-3.9% lesser performance. This data suggests that the difference between the systems mostly comes from the testing conditions not accounting for the energy used by the blower to overcome the resistance of the ductwork, which indeed is the flaw of the new rating.

    The study can be accessed at:

    Martin Hallaway continues to cite Prof Kavanaugh:
    “In the February 2013 EDU interview, Kavanaugh said, “To calculate performance on these multi- and variable-capacity models, the standard [ISO Standard 13256-1] calls for water temperature in the loop to be 68°F, which is ridiculous, because loops operate at much higher temperatures in cooling. Essentially, what you have there is a something similar to rating the efficiency of a car or truck … when it’s rolling down the hill. If the evaporator coil is 80.6°F and the water coil (condenser) is 68°F, you can get a ridiculously high efficiency reading. On top of that, these calculations assume that the fan has no static pressure. … When you take that piece out of the rating, you get a very deceptive, high efficiency rating.”

    Geothermal efficiency benefits from colder loops in A/C mode and from warmer loops in heating mode.
    So Prof. Kavanaugh (your expert) states that 68F loop temperature is ridiculous and way to low. Really?
    Our monitored loops start to provide cooling in May at 35F and top at at the end of the heating season between 55F and 65F, meaning that they perform about 15-20% better in cooling mode than rated, which is more than enough to compensate the not account ductwork in the rating system. Similar things occur in heating mode. The ISO 13256-1 standard uses 41F in 1st stage and 32F in second stage. Our loops start the heating season in October at 55F-65F degrees with the heatpumps running in 1st stage until mid December (the the average 1st stage temp is around 45F), when the loop has dropped down to 35-40F and the second stage starts more running. Then they drop further down to 30-35F, for an average 2nd stage loop temperature of 35F.

    This math can change if your move further south, where the heating would run more efficient and the cooling would be less efficient, but the fundamentals remain the same. If the designer is skilled enough bring the entering water temperature within the temperatures used for the rating, the geothermal heatpumps will perform better than the rating system indicates.

    So you can see Martin Holladay was not checking his facts and lacked understanding of the issues, and you just took it from him as hearsay and used it in your article to blame the industry for setting false expectation for your miss-performing geothermal system. I will post a similar replay on Martin’s blog.

    If you portrait the entire geothermal industry as problematic because you picked inexperienced installers without design experience, and use other arguments which are hearsay, not fact checked and could not be further from the truth, you loose more than the efficiency of your geothermal system.

    You loose your credibility.
    If you

    • I loose my credibility, eh? Jens, you work for the industry! There is a slight conflict of interest where you are concerned. I’m a homeowner with a geothermal system. No one wanted (or wants) my system to be everything that was promised more than me! If I felt it was “all that” I’d be delighted – giddy even — to share that with my readers. And, I’m open to any other homeowner who comes to me with a more satisfying experience. I just haven’t heard from one yet.

  24. Great article – I have a friend who has geothermal and have heard others who have geothermal with similar stories. I did a ton of research before we built our earth bermed (natural geothermal), passive solar house but as a market researcher by trade it was way easier for me to research although technically there was a learning curve. I will say that although I hired experts I double checked things, talked to passive solar house owners, etc. What is certain so far in my homeowner opinion is:

    1) Well sealed envelope is top on the list. We went with ICF or insulated concrete forms – was the product used and the builder introduced ICF to the province so was well qualified to build it. ICF to the rafters. Rafters insulated with cellulose.

    2) Windows – triple paned, low e etc. basically the best insulated ones you can get in North America

    3) Fully using the ‘free’ energy from the sun or passive solar – so having the site reviewed and house situated to capture the best solar. And using the best thermal mass holder concrete for the floors. No in-floor heating as that defeats the whole point of using the sun to heat your floors to heat your house.

    4) Natural geothermal – earth bermed (non-mechanical) on West/North sides where the wind is the strongest in winter in our geographic region.

    Here is a youtube video tour of our house – We used 2 cords of wood as back up heat for cloudy days. We have no propane and electric only for the hot water (solar hot water soon as budget allows). Total energy used 2 cords of wood, 12kwh a day (with 3 adults) or 4320kwh/year. We limited our mechanical systems to minimum or code required HRV we have. Very happy with the house’s performance. We do plan to add airlocks for the doors to keep more heat in.

  25. Geo-coupled heat pumps I assume. Incredible results when designed correctly. Sometimes EVERYTHING goes wrong.
    Murphys law, in spades.

    Sorry to hear about this near-disaster, Trish. The comments above already contain what I would say. Oversizing AC systems is a cardinal sin, btw, hell and brimfire await them.

    So many things have gone wrong that maybe someone shouldn’t be in this industry anymore? professional license. Sounds like possible mal-feasance.

  26. I have a Trane geothermal system. I figured I’d weigh in my opinion. I put my system in 2006 and got there 10 year warranty. I had service out over the last few years. I got about 4 years of no problems then a flow pump went out took 2 weeks in 2010 ,then again in Aug. 2012 took another 2 weeks ,and now here’s the great news fall of 2012 they we here for it because it had ice build up and put a part in this took a week and a half to two weeks before they got the part and put it in. Oh it gets better..On May 19-20th it went out called they came out 22-23rd ordered a part that took 10 days installed it on the 3rd still not working ordered another part took 10 days then installed it still down on the 13th..ordered a new pump got it on the June 21 I had to have the loop guys come out to flush it and put my pump on that was Monday the 24th. Still down the flow center was leaking now as I write this I’m waiting for that to come in.That’s gonna be 6 weeks down if not more. What a joke. No one is talking to me about why the pumps keep going out. Just keep putting parts on and no caring about why it’s burning up pumps. The warranty is covering the parts so I’m glad but in 3 years I’m on the hook. But it seems like if you paid out of pocket your parts wouldn’t take so long to come in. Oh buy the way it cost me for the loop guys to flush and pressurize my lines. This will be the fourth time to have them out when the new flow center is in to try again..about 200-250 each time there here. Not a one word from Trane about there system after I sent them the stuff they asked for. I was told now there going through a 3rd party for warranties from now on good luck with that. Is geothermal a good thing? I think it is but if you look around for complaints about there systems it looks like all these big name manufactures are lacking in service and fixing there flawed products. Just like all big businesses there putting crap in there systems to make bigger profits. I would like to see our government make them do recalls like we do automobiles so there forced to fix the crap there building today. They might put in better components if there held accountable. These systems should last like they claim they should. If you do some research many of these companies are owned buy the same company. So as for my thought on geothermal it’s the only way to go, but as of today there’s no accountability to protect us after there warranty expires. If your stuck fixing it later on because they never fixed the issues with your particular unit. You better have all that money you should have saved for parts and labor charges. So for now unless something changes in this industry when my system is done I will be putting in a gas furnace or something else. Geothermal industry will suffer when we stop buying there products because who can afford the up front cost then need to pour money in the system after there warranty.Many of the electric companies are not offering all electric breaks to the person who who may buy your home in the future. If you decide to go geothermal I wish you luck. Hope your luck is better than mine.

  27. We bought a $100,000 WaterFurnace geothermal HVAC system in 2008 for a house under construction. We did our research. We picked a large WaterFurnace dealer whose owner was a licensed PE with geothermal certifications. Well, the system didn’t work properly from the beginning. We gave the dealer 9 months to fix it. Unknown to us, he was secretly selling his business at the time. The system was not fixed We finally fired the dealer. WaterFurnace was of no help to us, by the way. We hired other people for even more money to re-design and repair the system. We sued the first dealer. After a two week jury trial, we obtained large judgments against the dealer and the owner. Our attorney fees exceeded $500,000. They are both now in bankruptcy. Is this a problem the average homeowner wants to touch with a 10 foot pole? I don’t think so. My problem (so far) has not been the WaterFurnace equipment. But from what I can see, these companies mainly give only lip service to the concept of customer service. They don’t seem to care about installation or design problems. And that’s the reason homeowners need to avoid this technology.

    Are heating and cooling costs lowered? I have no opinion on that.

    Our problem was a bad design. We did everything we could to insure we would get a good job but in stead we got a very bad job. A badly designed system cannot work properly .What does a homeowner do, hire an onsite engineer? There’s no way for the homeowner to protect himself. I see that excuse of “bad design” constantly in these forums and discussions. That alone is reason enough for homeowners to avoid geothermal HVAC systems. The numerous risks are simply too great.

    Conventional HVAC equipment is justt more reliable and plenty efficient. Homeowners are on their own when they buy geothermal HVAC systems. They have nobody to look out for them. The geothermal HVAC industry has created a bad reputation for itself, unfortunately. My builder and architect specialize in large custom homes and they tell their customers our story if they bring up the subject of geothermal HVAC, and that shuts them up fast. Any homeowner contemplating geothermal HVAC only needs to ask around and the advice you will get is “stay away from it”. For Congress and state governments to be offering tax credits for geothermal HVAC is enticing for many, but that’s not a reason to buy these systems. Homeowners who take the time to investigate this topic will be scared off by all of the horror stories. My advice to homeowners is to stick with reliable conventional HVAC systems that don’t have a multiple complexities and things that can go wrong.

    • East Coast,

      You very well expressed every single thought running through my head as I experienced my own problems. And you identified what I consider the greatest risks to a homeowner who chooses geothermal. Depending on your region of the country finding qualified designer/installers can very, very difficult. Of course, to the average homeowner, they all sound qualified. They all sound like they “know their stuff.” And when it turns out they don’t, it is one very gnarly path a homeowner faces to get the situation straightened out. It is also potentially financially devastating. And you are right, this is not a situation that any homeowner wants to touch with a 10 ft. pole.

    • East Coast,
      Sorry to hear about your geo situation, if it is indeed a truthful senario. Your post reeks of a geo discredit…for an HVAC gain. I apologize if mistaken.
      I’m a geo designer/installer based in the Canadian Rockies. Our region is without nat. gas so geoexchange makes so much sense economically. Let alone environmentally. Of course it has to be done right. That’s why we go to school and get certified and pay fees to a professional body to play watchdog and crack the whip.
      Sure geo is more complex than conventional hvac, but not a lot. Compare a 1964 Chevy to a 2013. You are going to get way better economy but don’t expect the local gas station to service it.
      I entered this business a bit like the Remington shaver guy. Liked the product so much I bought the company. I had my home retrofitted after 5 years of high propane boiler bills. Without a word of a lie, my heating/cooling costs dropped 80%. (my original boiler was 66% efficient)
      I have designed 200+ systems and have yet to have a complaint. Just the opposite in fact as most of my work comes from word of mouth. And I’m busy. So it gripes me to read a post like yours, tarring and feathering geothermal expectations in general. You got ripped off due to a lousy designer/installer. Cripes, for a $100k, I hope that waterfurnace was gold plated…I think you cheated on your “homework”.
      With respect to conventional systems being reliable, that’s a joke. Right? I had a local furnace repair guy out to fix my boiler at least once a year.
      Here’s the dirty truth: no matter what you install, someday it is going to cause some grief. The beauty of geo is that: in between those days of grief, it is going to keep the bills and CO2 to a minimum. Period.
      I don’t know how dealers/contractors perform due diligence in the States but up here in Canada we have the Canadian GeoExchange Coalition. They are responsible for training, certifying, and accrediting individuals/companies in design and installation. And they take their job seriously. If you are looking for a designer/installer, make sure he is a member in good standing with the appropriate association in your region.
      I hate to see the bad mouthing of a wonderful technology because of a few bad apples…

      • John — please explain how my post reeks of geo discredit. I said I was still a fan of the technology. And I’m not sure where I said all conventional systems are reliable. Trust me — I’m well aware that a contractor can botch up just about any installation out there. And crappy equipment of all types exists, although most problems, I do believe, are the result of misapplication. And misapplication of residential geothermal systems is a HUGE problem. If you’ve spent any time in the industry, surely you know this.

        I also don’t know what you mean by “….for HVAC gain.” What does THAT mean? You think I sell an alternative product or something?

  28. I recently finished a house build – earth bermed, highly insulated, high quality windows, passive solar/’almost’ Passive House etc…..I used two 9,000 BTU ductless mini splits (Fujitsu, cassette/ceiling mounted) at a cost of $3,500 including installation (I’m a general contractor, I mounted the units – my HVAC guy hooked them up and ran the lines). I live in Maryland (zone 4) my house is 2,000 SF and my average monthly utility bill over the last six months has been $95. Needless to say I am delighted. I should qualify this by saying our house has a very open floor plan, otherwise more units would have been necessary, also lso we have a pellet stove for back up heat. I think ductless mini splits are the wave of the future, they are way cheaper and more efficient than geothermal. I have a blog that details the system

  29. What fascinates me about all of the slightly negative response on GEO, is that most of the

    system choices are for ground-loop. If you consult ANYONE in the realm of GEO, and perchance

    check the actual specs of the unit you’re purchasing, there are NONE that advertise COP or SEER

    better than open-loop!!!…it’s a no-brainer, and it’s not expensive. Bore a well, route the plumbing,


    No heat-strips or back-up emergency heat, no wood stoves, just consistent performance with

    so-far ZERO problems. System is 7 years old in well insulated home.

    • Hi R.E.!

      Thanks so much for your comment. I think you bring up an important point. In fact, I recall a conversation with my favorite geo contractor about this very topic. However, I remember him saying that the COP ratings manufacturers give do not include any energy used by the water pumps. I’ve read that this energy consumption can actually be quite significant.

      We have not covered a ground water geo system yet on Greenspiration Home. if you would like to write about your own system, I’d be interested in publishing what you have to say!

  30. Interesting read. I have a friend who has been HVAC for a long time. They were very excited about the technology after learning how well it works from a relative. He talked me out of it saying they prove to be efficient at first, but after a while they lose their edge, and require substantial maintenance at 5 years or before, and that there is no payback.

    My relative heard both sides, but heard about a guy from a co-worker that did just these for a living, was happy with his, and that the installer was more of a scientist than anything. My relative called him, but the guy wouldn’t even come out to his house. He told him the experiments he wanted done, and to e-mail him the results. If the results were favorable, he stop out. He told him it would be about a year and a half before he would be able to put it in. The results were favorable, and he got on the list. It took over a year, before his house came up. The relative has nothing but praise for the system, and has been on it for I’d guess 7 or 8 years now, with no problems, and still saves tons of money. I have a natural gas condensing furnace, 93%, and it costs him less than me to heat, and his house is bigger, and couldn’t be more efficient. My friend in the HVAC business, was factory trained, and their company installed them properly, but there was no scientist thinking involved, and often they didn’t meet hardly anybody’s expectations. The scientist guy won’t even show up if you don’t so tests first, and he won’t do it for love or money if he doesn’t think your site makes sense.

    I went with 93% natural gas condensing furnace, and natural gas was twice the price at the time. From talking to my relative, it’s not likely my site would be that good, so an ROI didn’t look even remotely possible, and now NG is half what it was. I’m not even sure I can even make a case for a condensing furnace without a pretty good size home, but I have the sealed combustion, long warranty, and lifetime on the heat exchanger, even if is break even. So I made the right decision. The relative was on propane, and had a quick ROI. Propane costs 5 times per therm what natural gas costs on a good day, while on a bad day, like today, Propane costs 9 times as much.

  31. Add my name to the list of dissatisfied Geothermal customers and I applaud the author for sharing. I have a 5 ton and a 2 ton FHP system running in an open loop Pump and Dump configuration. This system came with the home I purchased 1.5 years ago and it is now a 7 year old system. Since moving in this system has been nothing short of unreliable, expensive and ineffective. I have gone through several “geothermal” companies here all of which have promised to fix the problems that range from water quality issues to loop design to cold weather freezes that have resulted in me dumping literally tens of thousands of dollars into a system in a band aid fashion all of which have resulted in me being no better off 1.5 years later. I am disgusted with the lack of regulation around the contractors that install these systems and sell them as “green”. They have no idea how to optimize the systems to perform efficiently nor do they care. They get your money, do a “fix” and when it doesn’t work they don’t try something else for free, you pay again and again and again. I’m currently evaluating the costs of replacement with conventional heat pumps because the last cold weather snap froze the return lines and burned out the compressors (at least that is their THEORY). I have no assurance that is what really happened and there are not diagnostics onboard to help confirm anything other than the compressors are shorted to ground. I can’t tell you how disappointed I am in this industry and the lack of qualified personnel to deal with them.

  32. We put a geo system in our newly built 2000 sq ft home this past September with Schumacher Home builders. I have been disappointed with our $400 monthly electric bill. ($450 last mnth). Even with the harsh winter, I expected way lower electricity bills. We are all electric. I have a feeling Schumacher cut corners. When they put our windows in, the energy star rating sticker on them showed the windows were energy star for Georgia! The system is quiet and we haven’t had and problems with the sometimes -20 degree wind chills we’ve had this year. I haven’t been able to find any comparisons for what we would probably pay if we had a standard HVAC system. If I found out I was saving $100 a month then I might not be so disappointed with the Geo “savings”.

  33. My experience has been the same. Massive investment. Massive bills. Absolute rubbish. The water furnace system requires so much electricity I might as well have just installed an electric heater for 1/5 the the price

  34. I am so glad I found this site. All of your posts have been very interesting.
    I have a geo and it is ok. Had some problems in the beginning but after that all is well. My bills are very reasonable. My unit is about 10 years old and I am being told that it will need to be replaced in the next year or so. I have two questions I am hoping someone can help me with.
    First, can a geo be used in the electrical heat mode a lot or will that hurt the unit somehow.
    Second, I am noticing a really hot smell in the air. Do you think that is a sign of something going
    bad with the unit.

  35. It would seem prudent to consult with at least 3 contractors before choosing any system. I didn’t see where the writer did this.

  36. Hi Trish:
    I live in Ottawa, Canada and I have been researching online on homeowners’ experience with geothermal because we are planning on building a home and have heard pros and cons about geothermal. Thank you for sharing your experience regarding geothermal and for your concern for homeowners in this regard. I am very glad that I found your website which has provided a lot of helpful information regarding owners’ experiences on this subject.
    I have spoken to some owners who have geothermal in their homes and they seem to have a common response that if you live within the city and there is an existing gas line, it will be more cost-effective to stay with the gas company instead of installing geothermal. It will be a 3700 sq. ft home when built. I wonder if any homeowner who has geothermal provide us any advice? We will appreciate your response.

  37. My husband and I did our research and felt Geothermal was the way to go back in 2012 so we dropped all our savings into one. When we finished construction of our new single floor 1,900 sq foot custom ranch, we were apprehensive about the initial electric bills because we expected it to be lower. 2 and half years later, our relatively smaller home is still costing us $450-500 per month in electricity! We had our initial Geo installation company come back out several times to do tests and even got a second opinion from another Geo company in which we were told the Geo system is working just fine. They looked at every electrical component and turns out the electrical back up still has never even turned on. We’ve recently had another energy assessment conducted to confirm our house is very efficient. We did take the time to select anything “efficient” when building as possible. Because we have nothing more to lose at this point, I even called a Solar panel company and they expecte to see a 3-4,000 sq foot home based on the electric bills they saw. Bottom line, we’ve been royally screwed. It’s just 2 people in a 1,900 sq foot home and we aren’t even home during the day! NO ONE can figure out why our bills are still so high. We spend so much money on the system that we must continue suffering or eventuallysell our dream home…so incredibly disappointed. At least I now know I’m not exaggerating the situation nor am the only one that is dissatisified. Thanks.

  38. Built a new 2,600 square ft. on main floor ranch home 2004 in the Midwest and decided to go with GEO as plan to be there for good. It is very well insulated. Have a closed loop system, loops are a good 10′ or so down, with 6 ton FHP. Also in floor heat or can run through an air handler.

    The system has had issues just about every year since new including a new compressor the 4th year and an entire new unit just recently. Have only been heating the upstairs.

    It was sized and installed by a very reliable contractor that does only GEO and has been doing so for many years. They have checked things out many times, loop temps, flow, etc. etc. and everything is always within specs.

    My conclusion after 9 years of repairs and replacements, average $300.00 to $400.00 per year, not that great of electric bills, almost freezing up when on vacation, -10 degrees with a dead compressor, and no backup heat because they wire the thermostat to the control wiring for heat pump, and it does not work with a blown breaker. Where was I, oh there is a reason its called a FLORIDA heat pump. I think its works great for AC but after running hard in cold weather it is tough to get 20 some degree water up to 100 degrees.

    I asked the contractor if it was a big enough unit before replacing and they say it should handle the total 5,200 square ft with no problem, even though it cant take care of the 2,600 we are trying to heat. Again, great for AC and maybe down to 20 degrees or so but that is about it.

    Yes I am putting in gas as it will no doubt be much more cost effective, and comfortable when really cold.

  39. I purchased a ranch home with a ground water geothermal system that was installed in 1987. It worked well and our all electric home averaged about $175/month. In February we decided to put in a newer unit that would also provide hot water. We have seen near 20% reduction in electric consumption and have just gone ‘online’ with a 9100kw solar system.
    It is true that geothermal is often touted highly, especially by sales people, however, there is very accessible info regarding geothermal and the expression ‘let the buyer beware’ is always good advise.

    I also understand that geothermal is not for everyone, since it doesn’t provide the same ‘blast of heat’ that gas and oil does, but last winter was cold here in central Ohio and our system kept us very comfortable and our electric bill never exceeded $225!

    I plan to install geothermal in all our other dwellings and will recommend it to friends and family.

  40. Cool. You guys just talked me out of it. Thanks.

  41. I just installed a geo-thermal HVAC system. I wound up spending a few more dollars to purchase a smaller well pump. Went we first started, they had me running with a 1.5 horsepower pump. I have replaced it with a 0.5 horsepower pump and still have more pressure than I need.

  42. I’ll drop a note here as well.
    I am in Mass. and have had Geothermal since 2009.
    2000 sq ft home, all re-modelled. Meaning insulated, new windows etc.
    i have a Climatemaster 5 ton unit.

    The electric backup heat was never hooked up! (Not needed)

    Electric bills are huge. Though when you total what I use to pay for oil to what I consume in electric bills I come out around $500. and that is probably higher now since the cost of oil is always rising. But so is the cost of electric.

    Anyways, for 2013 I paid $3200 in electric. Worse months are Jan and Feb; with Feb being about $500.

    I have brought in 3 contractors to look at the system and the last one (who was recommended by the manufacturer) says the system is correct.

    I did some updates to the system for piece of mind and I think that is about all I can do.

    I am looking for comments from consumers on their electric bills. Do you find them higher or lower?
    Most consumers I talk about think it’s outrageous, and thus i called in multiple contractors.

    I am trying to get the electric company to replace the meter as well, though I find this extremely difficult, right now.

  43. Real simple and all to common: you got a bad HVAC contractor! The problem is not the technology and not the industry … it is the HVAC contractor. If you are in NC, then get the HVAC board involved ( — they do not tolerate mis-sizing a system.

    If you need more help, then either contact a Certified GeoExchange Designer (CGD) in the area or post a question on the Linked In GeoExchange group ( There are many highly qualified geothermal experts who monitor and comment in that Linked In group, and they are all glad to help with problem sites.

    Full disclosure, I too am a CGD and also an IGSHPA trainer. If you need help dealing with a bad HVAC contractor then give us a call ( But, contact the HVAC licensing board for sure.

  44. We just spent 26k (18k after tax credit) on a Water Furnace Series 7 5 ton unit and a closed loop horizontal installation. My Geo usage for cooling today was 26kwh. We cool 2700 sqft on the top floor with 700 sqft in a walk out basement. R44 of fiberglass in the attic. The house was built in 1980, all brick and located in Eastern TN. We replaced a 35 year old 4 ton GE and a 3 ton 2007 Lennox unit. As well as 2 35 year old gas furnaces. Last year we used over 5000kwh for the month of August. This year after the Geo 2200 kwh. We currently pay .10/kWh.

  45. I soon plan to start construction on a 7000 sq ft home (6100 living) in the panhandle of Florida. Home will be ICF with a lot of south west facing glass (670 sq ft). Also a 10KW solar PV system.
    my original plan was to use geothermal for heating and cooling. From numerous friends I have they all have been satisfied with their systems. That means 2 in Florida, 1 in South Dakota, 1 in Ohio. All Water Furnace but from reading Climatemaster it seems to hardly matter as they are all close in performance.

    What I have read almost every time when reading about dissatisfied geothermal users is that universally the contractors oversized their system. I honestly think when a manual J was calculated it was NOT calculated but used a rule of thumb and added to it just to be safe.

    I plan to use an independent PE to verify the manual J as this seems to be the main problem for most systems. Just think about it if the system is oversized that means that an owner had more wells dug then needed, larger tons of HVAC than needed, less than optimal heat recovery for the desuperheater and on and on and on. It is no wonder that some are dissatisfied. I would love to talk to Jon and a few others as to how they sized their systems for their customers because they all seem successful.

    The only case I am aware of where a system that was replaced (20 year old 5 ton WF replaced with a new 5 ton WF) with a new system of the same size and never worked right was an owner in Ohio who used a pond. The loop was checked by the installation contractor and verified to be adequate. The owner went through hell to get the system working right and after 1 1/2 years the problem was the loop size was inadequate for the new 5 ton unit. This soured the owner on geothermal who had a previous unit running for 20 years.

    Point is that sizing the equipment to include heat sink used requires someone who knows what they are doing and that isn’t limited to the installation but goes all the way back to the manual J.

    Appreciate all the good information. The cost of a geo system is too expensive to have any component done wrong.

    This is like putting a Corvette engine in a Geo Metro. Yes it will run but will run all wrong…

  46. We hade our system installed in July 2014. I have yet to see the Geo compressor use more than 30kwh per day in cooling or heat mode. Our last 2 bills have been under $120 @ $.10 KWH. 3450 square feet home with 700 feet of walkout basement. I would recommend a whole house energy monitor to track the energy usage on the Geo Compressor. Our home is insulated well in the attic (r60)but the windows are nothing special and we have living space over the garage.

    For 11-26-2014 in Eastern TN

    59 kWh usage for the entire day. Estimated electricity cost for the month of November $130.

    Geo Compressor 16kwh
    Dryer 11.3 KWH
    Waterheater 9 kWh
    Office 4.43 kWh
    Geo Blower 3.6 kWh

    Temp for 11-26-2014 in Eastern TN was between 40-50 degrees.
    Thermostat set to 71-72

  47. As of today 11-28-2014 the Geo Compressor has used 361 kWh of the 1280 kWh for the entire month. Our Geo Compressor accounted for 30% of our total bill. That is an average of 13kwh per day for the month of November. The blower used 78 kWh for the month so that is 439kwh for the entire system. This would account for 34% of the entire month’s electricity usage.

  48. Hi Trish.

    I live in Southern Alberta, Canada and have a 6 ton GeoSmart Dual Capacity system with 6 holes drilled 220′ deep. The main floor of my bungalow (1718 sqft) is heated by water to air exchange and the basement (1680 sqft) is heated by water to water radiant infloor heating as is my garage (690 sqft) with the garage thermostat is set to 12C (54F).

    When we were building, I had a separate electric meter installed in my basement to monitor just the geothermal system which also records the energy used to operate the desuper heater. I also recently installed a TED home energy monitor & both these meters are within a few kWh’s of each other each month.
    The energy used for 3 years from Jan.1/11 to Dec.31/13 for the geo system averages 7131 kWh/year & the whole house usage averages to 25,572 kWh/year.
    The geo design summary supplied by the dealer showed a projected heat/cool/desuperheater usage of 11,293 kWh/year so my actual usage of 7131 kWh/year is well under the target.
    I am guessing the company that installed the geo system had not worked much with a well insulated & sealed home & over compensated. They had a good reputation for installing geo systems but may not at that time had the knowledge for better than average energy efficient homes?
    I had a blower door test done after we moved in 5 years ago & we achieved a 1.19 ACH & an Energuide Rating of 88. The walls are 12″ thick ICF for the walk out basement & 3″-3.5″ closed cell spray foam on the main floor. The attic has 1.5″ spray foam as a base & enough blown in rock wool insulation on top to achieve R60.

    So, the 7131 kWh annual usage is under the projected target even though we had a $555 energy bill in Jan/11. This does not seem to make sense………
    The actual geo usage for Jan/11 was 1733 kWh & the whole house usage was 4009 kWh. So yes the bill is high for that month, but when geo energy usage is averaged over the year, the geo system seems energy efficient compared to the dealers projections.

    I don’t understand all the influencing variables so I can’t say much more, but I enjoy the stable room heat of the geo system vrs a natural gas fired system & because we don’t have any natural gas hooked up to our house, I can use solar pv panels to offset the electrical cost of operating our home. We actually installed 48 x 260 watt panels this past summer so looking forward to seeing if we can achieve the annual 19,000 kWh expected solar production.

    I hope to net zero some day by continuing to lower our energy usage, but I can install a few more panels if I need a bit more help to get there.

    To add to Jamey Stubblefield’s last post, I’ll list a what I can for comparison purposes for Nov.1-28/14:
    Geo heat pump & desuper heater used 1092 kWh Nov.1-28 out of the whole house usage of 2200 kWh.
    The Geo used a high of 67 kWh on Nov.28 but the ambient temp was a low of -29C (-20F) with a wind chill of -35C (-31F). The daily average usage for Nov.1-28 is 39 kWh for the geo & 79 kWh for the whole house.
    The geo is 50% of the total energy used.
    The only other item I currently monitor is the hot tub which used 13.5 kWh on Nov.28 & 285 kWh for Nov.1-28.
    One other energy draw is a convection recirculation line from the last hot water tap to the domestic hot water tank. I have calculated a daily standby electrical draw of 4.8kWh/day or 1752kWh/year due to heat loss in the hot water lines. This is a fairly high electrical load but I would not trade the pleasure of having hot water at the tap within a few seconds.
    Maybe the energy consumed by the geo system is higher than it could be, but it seems acceptable to me when averaged over the year.
    I don’t know if 7131 kWh is high for heating/cooling the sqft of our home & garage, so if anyone could give me an idea, I would very much appreciate it.

    David Takeda

    • Hi David,

      Just for a comparison for you, our all electric 2000 sf, 2 story home (living space only does not include basement of 726 sf) air source heat pump (vintage 1998 same age as house) used 20,064 kWh in the last 13 months.

      We are soon replacing this 16 year old system with a 3 ton, 3 vertical wells, 175 feet deep, ground source heat pump. I am very much looking forward to seeing if it lives up to the projected savings though I am being very realistic in my actual expectations.

      Our current MO is to use a Little Gray box on the hot water heater to regulate how frequently it runs.
      We heat the house to 68 during the winter and to set back the thermostat at night to 62. Summer cooling is kept at 78, we use windows and ceiling fans at night for sleeping. The house is well insulated but not super insulated, good windows, doors, 2 x 6 construction. We also have to run a dehumidifier in the summer to protect wood working equipment in the basement. We also burn wood in a wood stove insert a few hours each evening during the coldest months.

      From what I understand with the new ground source heating system temp set backs should no longer be necessary and our hot water energy generation cost should be greatly reduced. the new system should be better at dehumidifying the house as well. We shall see.

  49. I have a geothermal system since 2009 and I’m about to dump it next. Probably going to LP. (Not sure)

    The contractor dumped a 5 ton Climate master in my house of 1440 sq feet and from what I can tell it’s oversized. 2 400 closed loops and r30 in the attic.

    I have had 4 contractors come in and most blame the improper insulation of the house.
    It’s always something other than the geothermal but no one wants to fess up.

    My house (1940′s) has been completely re-modeled. Meaning all walls, floors removed, built and re-insulated.
    Modern windows, doors etc.

    I also added a business office to make the house come to a total of 2K sq feet.

    The energy costs of running the geothermal system (electric) is way too high. Last year we are talking roughly. $3500 for electric only.

    I purchased an energy monitor and attached to my electric panel and went through the entire house.
    All LED where needed and now we have lowered the thermostat down to 64 unless absolutely needed.

    In Mass. our electric provider has announced a 37% increase per month for “supply” costs, not usage. So I’m expecting some very outrageous bills.

    I have also looked into downsizing the system but in reality your stuck since the wells are tied together.

    I have read for years on a lot of bulletin boards like this one of people complaining about their electric bill. I can imagine that the contractor who installed it was just as incompetent as the one I had. (Now out of business)

    Be careful on who you select as the installer and make sure you get multiple quotes and force them all to show you the manual J calculations. If 3 contractors come in around the same calculations, then you can at least think they all know what their doing or all 3 are bad.

  50. A fascinating post, great real world stories! Trish, thanks for getting this started with your post.
    I’ve wanted to switch to geo thermal for a while, and am happy I’ve not been able to afford to because I’ve found out so much about it, a bit from profesionals and installers, but mostly from real world experiences.
    The original post included little data to guess what the problem was, simple oversizing is not a deal breaker, unless there were going to be only marginal savings. As that system still isn’t saving much, I have to wonder what other problem there might be.
    Many have hit on typical problems, and I’ll double down on them from the research I’ve done:
    1. Loop capacity, which is more than size, some effort needs to be made to quantify the energy the soil / water table in your area will transfer.
    2. Minimizing load by insulating, air sealing, installing a heat recovery ventilator, etc, which will cost much less than a bigger Geo system, bigger ducts, more radiator, bigger loop, and worst of all, bigger elec resistance backup.
    3. Post installation monitoring and “tuning”. These are CUSTOM built systems, due to varying soil conditions if nothing else. Any installer that does so and runs, isn’t the installer you want. Find one whose customers confirm post installation follow up.
    4. Electric resistance backup heating. Sure get it, then make sure it’s on a clearly labeled switch and leave it turned off until that winter when the geo fails and the house starts to freeze.
    5. Trying to reuse undersized ducts, uninsulated ducts, ducts in attics, crawlspaces, etc.

    Good luck everyone with your installs, do your research, get multiple bids, and an engineer when all else fails.
    Russell Higgins AIA

  51. Thank you Trish for starting this post, it has prompted input from recognized experts in the technology and is providing a tremendous resource for those learning about geothermal heat pump systems.

    We’ve been following this post and it continues to motivate us to provide independent monitoring services for residential geothermal (ground source) heat pump systems. As Russell points out above, the systems are unique to building and ground conditions and post-installation monitoring is essential.

    Most commercial buildings have a data acquisition system that enables building owners and engineers to identify, troubleshoot, and fix problems that may arise with the various aspects of a geothermal heat pump system. Whether a problem is due to design, installation, or maintenance, data is essential. Our monitoring systems provide independent performance metrics that demonstrate the system is operating as designed or, if it isn’t, the data necessary to identify the problem and how to fix it. We have also put together a white paper “Homeowners Guide to Geothermal Heat Pump Systems” that can be downloaded here: that echoes much of the advise offered in the post and comments above.

  52. It is my belief that a horizontal loop system is better suited for the southern climates. I also think Geo is a better performer when it’s use is primarily for cooling. If the Geo has to switch over to emergency heat (I think our threshold is 10 degrees F which we hardly ever see) then the efficiency is lost. Before anyone considers a Geothermal system I would highly recommend a whole house energy monitor. I found that I was able to address another 20% reduction by making some adjustments to lighting, insulation, computer usage, and a plasma tv that was using 400watts per hour.

    Since January 1st our electric bills (all heating and cooling is electric,approx. 2700sqft upstairs,700 downstairs, East TN) are thus:

    May 1162kwh ($116)
    April 1332kwh ($133)
    March 1723kwh ($172) installed insulated garage doors.
    February 1940kwh ($194)
    January 1934kwh ($193)

    This is roughly 8100kwh for the year so far.

    According to my whole house energy monitor the Geo has used 2973kwh for the year.

    average 20kwh per day for Geo and 54kwh per day for whole house.

    37% of our daily energy use is consumed by the Geothermal.

    Lots of factors to consider….one that I always like to bring up is the affect that Geo has on our electric water heater usage. Our 85 gallon Marathon electric WH is rated @ 13KWH/day. Because it receives preheated water from the Geo it only averages about 8/kwh per day. That is a 750kwh difference so far this year. From 1/1/2015-5-31-2-15

    A conventional HVAC system does not increase your electric WH’s efficiency.

    Before the Geo and energy audit adjustment we were using 43,000kwh per year which did not include the natural gas heating cost of additional $800. $5k total.

    This year we are on track for 16,000kwh with no additional natural gas heating costs. $1600

    Longevity of Geo

    25+ years on the Geo Compressor. It is located inside my garage in 65-74 degree temps year round.
    50+ years on the loop?

    Longevity of traditional HVAC:

    15+ (not sure about this number. Our previous units lasted 35 years but I am told they are not built to last this long anymore.)

  53. For actual, real numbers, you can see over 6 years of electric usage with an air source heat pump vs over a year of usage with a geothermal heat pump here:

    I’m saving money, but its not as much money as the sales guys tell you you’re going to save – at least it wasn’t in my case. Still, if I had to do it over again, I would get the geo system, but that’s because the price difference between air source and geo wasn’t that big.

  54. I had decided to go geothermal when natural gas prices skyrocketed before the fracking revolution in hopes of reducing my heating bill. Bad timing.
    What I did not expect is that air heated by a geothermal system is not nearly as warm as air heated by natural gas. During very cold winter days, the system runs pretty much 24/7 and AUX heat is on most of the time.
    In my case I would say the system is undersized for 2 months of the year. The system works great if the difference between inside temp and outside temp is no more than 30F. Great benefit in summer is that I get free hot water as a byproduct of cooling the house, and my gas bill drops to almost nothing.
    Now I seem to have developed a small leak in the closed loop, and water needs to be added regularly. We’ll see if it gets worse and what can be done about it. But if the closed loop fails after only 8 years and needs expensive repairs, forget it. I’m putting back a conventional system.

  55. We had a geothermal furnace installed this past December. Previously we had a gas furnace with a blower/central air system. The A/C was electric. The electric part of our utilities went up moderately over the winter while the gas was almost eliminated. However, as summer arrived I have noticed that our electric requirement actually appears to be up from last year in terms of kilowatts used and total cost. Any thoughts on what is going on? Should we get another contractor to conduct an inspection of our installation?

  56. I have to say that I am truly dismayed at the anecdotes of savings that are not realized by posters.

    I am also not surprised by that and at the same time not discourage as to the efficacy of ground source heating and cooling systems. I personally have been an HVAC systems designer and certified BPI Building Analyst for six years now and successfully designed/implemented over a hundred and twenty geothermal systems without one of them falling short of modeled efficiency. That being said, I have also provided efficiency upgrade analysis to nearly equal number of non-geothermal systems. The bottom line is…it is all a matter of the legwork, knowledge, conditions and to some degree, integrity of the designer and business you are working with.

    Energy efficiency is energy efficiency. Cost is cost. Typically they do have a dependent correlation to one another but, not always and not always in scalar magnitude enough to translate into return.
    That’s a baseline caveat of physics to economics and still does not take into account the professionalism of the person(s) you are working with. The HVAC industry to be blunt, is fraught with incompetency for traditional systems to say nothing of something that folds into it aspects of additional thermodynamics, geotechnical analysis, economics and fluid dynamics.

    Websites that do a down and dirty analysis like that of Waterfurnace have a healthy margin of error in both the detailed analysis of building envelope/system parameters/historical consumption to say nothing of inexpensive solutions that impact the overall summative heating/cooling load.

    Additionally, some of the disconnects are endemic to the industry and some of it is endemic to the way in which we handle energy in our country…federal, state, and local. I have unfortunately seen bad analysis and systems on homes buildings etc. and it is across the board from average homes to multi-million dollar mansions.
    Three recommendations that will go a long way to provide success…
    1. Have an envelope energy analysis performed by an independent analyst. Preferably a BPI certified analyst, HERS rater trained or similar. (This is commonly referred to as a “test in”)
    2. Make sure that the system designer is using competent computer modeling software. ACCA speedsheets are fine for load calculation but, when it comes to the actual cost analysis of energy consumption, there is no reliable way to do this the old fashioned way with paper and pencil. It takes too long and requires a lot of math….mistakes are easy to make.
    3. A well done analysis should look at ALL the upgrade parameters. Energy analysis should ALWAYS look for the best Return On Investment across the board. This is known as Whole Envelope Analysis.
    4. Ask for the findings and explanations.
    5. Ask the Analyst to provide a detailed summary/outline for system construction and get multiple bids from the proposed upgrades. (On your own or from the Analyst) Have the details of testable performance measures written into the contract (ie. building sealing measures, duct sealing etc)
    6. Have a “test out” performed on the building.

    This all takes case by case analysis considering all the details. Am I “pro” geothermal? Yes, I am positive about it as a largely ignored piece of the puzzle to energy and environment and still find it is a significant solution in 65% or more of cases but, I also have a higher calling to what is the BEST solution for circumstances.

    Quick note on what loop type is best….there is no best loop type except for what your conditions demand weighed against cost. It is all a matter of calculable physics and sizing things correctly.

  57. An oversized system? Does that mean it produced too much heat? And most of your costs are not in running the system, but in paying it down?

    Something I have long been curious about is if a home geothermal heat pump could be adapted to electricity production. I mean, sure, it’s not going to be as much energy as a low heat geothermal power plant, but if you can produce extra heat and if you can store that extra heat couldn’t you drive it through a small turbine? I wonder how that might compare to the cost benefit of solar or wind.

    For heating your home I would think that improving the insulation, eliminating air leaks, and putting sound proof second windows inside or outside your current ones to create a dead air space and/or using nanogels between layers of glass (can resist the heat of a flame thrower) so hold the temperature you have would have a larger impact than the source of your heat and should directly impact how much heat you need to produce.

  58. We got an estimate for geothermal in Maine. Small raised ranch around 900 sf above ground space. The installer claimed that we’d save around $150 per months in heating costs.

    The price for the system, installed? $45,000. It would take 25 years to see a return on investment, and that’s assuming we actually saved the $150 per month, every month. In reality, with several months requiring no heating or cooling in this climate, it would probably take well over 40 years to save as much as the system cost (not accounting for inflation).

    Buying a geothermal system seems like buying a new Energy Star refrigerator: they’ll talk about your savings, but you have to realize that it will literally take more than 40 years to have any actual cost benefit.

  59. I have been designing and installing hydronic radiant floor heating systems for over 30 years. Installed over 1,000 from Alaska to California, and designed over 4,000 system. I do over 400 a year now. A well designed and properly installed radiant floor heating system in a very well insulated home with a high efficiency combination water heater. Will often cost less than forced air to install, and will compare very close in operating cost of the best Geo system. In new construction, it is all about controlling the heat loss. Heat loss in the last forty years has gone from about 30 Btu’s per Sq. Ft. to less than 15 average, and to about 5 for super insulated homes. Most contractors and engineers still have not adjusted for that fact.
    Any money saved on insulation will be paid in monthly heating payments for the rest of your life.

  60. Interesting reading all the responses. I have two probably elementary questions. We have geo-thermal. I like to turn the temp down at night to sleep better. I’m told I can’t turn down more than 4 degrees…true? Is that even too much? And, when the words AUX heat shows up on our thermostat, no heat comes out. My husband had to fiddle with the system in the basement and I think he basically reset it. Obviously that shouldn’t be happening. Little frustrated we did receive “training” on how to use system. We installed this in new home we just built.

  61. I am looking at a house with a geothermal heating plant. I would be interested in knowing what questions to ask.

    I definitely appreciated the candid nature of this writeup. I definitely did NOT appreciate the many responses that essentially blamed the author for not crossing this “T” or dotting that “I.”

    Most people quite reasonably just assume that the furnace will work. I’ve been familiar with geothermal in concept for quite a while, but now that I’m looking at a house with geothermal in reality, I’d like to have an idea of what I am getting myself into.

  62. I agree with “Jens”, “John Managh” and “Zephyr” for the most part. That being said I also agree with the people who have gotten a raw deal with a geothermal HVAC or water well drilling contractor. The reason I say this is because most customers of geothermal systems do not know what they do not know, in other words, they do not know what to ask and why they should ask the question. The customer is totally relying on the contractor to help them out that is why they called him in the first place, He or his representative is supposed to be the expert.
    As a licensed master well drilling and pumping system contractor, trained HVAC/R technician to name a few, I understand all three sides of the equation. I could not sale an Eskimo a deep freeze but, I can tell the truth about something and that makes it much easier for me, as a professional. I also encourage the geothermal hvac systems over all else at today’s technology, if they are designed properly. Likewise, a business owner regardless of what business he or she is involved with must have the highest integrity to himself and the public in general, regardless of the $$ value, otherwise they should not be in business, my opinion.

  63. My folks had a Geothermal unit put in when they did an addition/remodel of their home. It was a nightmare. Finding qualified techs is near impossible and when they can’t figure things out, they blame it on the wells. A 40k install lasted 5 years, the installer went belly up and then reopened under a different name, all the manufacturers seem to have pretty a fair number of pretty serious problems.

    All I could say is don’t do it, don’t do it, don’t do it.
    The promise of the technology is great. The industry is not qualified.

    • Sorry about your neg exp,
      I’m a contractor in the HVAC business. 28 years exp. 50% of Geo’s I work on have under sized loops or incorrect piping design.
      I replace and rework more old installs then new one’s. I install 100% of my own work including loop piping. (I’ve learned most company’s source out loop work and go with cheapest price)
      When there installed correctly the work very efficient. Its not the Geo

      • HELP!!
        Read the articles. I understand I had the wrong contractor….From the first letter from the electric company in 2007 thinking I started a grow house for weed because my, to the system running non stop, to blowing cold air in the winter, to giving up on calling the contractor in the first year…I knew something was terribly wrong after he told me, “just buy propane its cheaper” after I had paid my bill.
        Over-sizing, under-sizing, duct-work, insulating, hiring another contractor…There are two things I don’t understand in this process…
        1) No one will touch the system/help with a resolution. I have talked with atleast 5 geo reps…given specs, some have come to my home…and no one will work with the system. All I want is to NOT have a 2016 Audi Se sitting in my garage and not driving it. (I have not used my system for years because it is too costly to use) I am not sure of any other investment that people ignore you if you have a problem. I’m dumbfounded when I read the other articles where people have had problems w/no resolve…for goodness sake your just going to say, “oh well you picked the wrong contractor???” That’s unbelievable…who is looking out for the consumers welfare??? Isn’t there some type of regulations for installers/contractors? These systems aren’t cheap!!!
        2) What legal action can I take or have others taken…besides the person who spent 500K???
        I wish I could ignore this problem…but it continues to haunt me!! This was my second year that I fell into a sink hole while mowing the lawn…last year I couldn’t figure out why I had fallen into a 3ft deep hole in my lawn…this year I woke up and realized that it is from the wells that were drilled for the vertical loop!!! Something is majorly wrong with this from a consumers point.

  64. I have a had the same geothermal water furnace for 20 years. It is made by Water Furnace company in Bloomington Indiana. When I had my house built the builder recommended this heating system. It has a horizontal ground loop. My house is 2300 square feet. The electric bill ranges from 120.00 to 260.00 bucks per month. My house is all electric.
    The higher electric bills are usually during the dead of winter. It has back up electric heat and It rarely turns on. The geo also heats the 80 gallon hot water heater. The hot water heater also has electric elements to assist with faster recovery. I recently have had to replace the two Grundfos ground loop pumps because they were making noise and were worn out. This cost me $440.00 for both pumps. I replaced them myself and purged the air out of the system myself. 3 years prior I replaced the taco circulating pump for the hot water heater assist. This cost me $180.00 and I did this myself. I flush the hot water tank every 2-3 years.
    I replace the anode in the hot water tank every 5-6 years myself for about $15.00 for each replacement. I have never replaced the 20 year old hot water tank. I replaced the compressor contactor about 2 years ago because it was sticking. I did it myself for $20.00. I am extremely happy with this geothermal heating system. It provides very even heat at a very reasonable cost. It is super quiet. The air conditioning is amazing. I can turn it on when the house is at 82 degrees with 80-90 % humidity and it gets the temperature down to 73 degrees in less than an hour. I think the maintanence is a bit more than a conventional furnace. This is a great system. I am very happy with it !! I would go geothermal again. I think the right installer and the right manufacturer makes a big difference.

  65. Please re-title this article.

    This is very unfortunate that you were unaware of the design necessities and led by an uneducated installing contractor. This happens a lot by band wagon geo dealers that are only in it for the paycheck, which is known to be more profitable than standard installations. This is due in fact to the “fudge factor” that has collectively been added to projects by irresponsible contractors.

    BTU’s are BTU’s! Geothermal is 400-500% efficient. No way you crack the nut will a gas furnace or air source heat pump be more efficient! If a proper load calculation was done, the proper dirt sample was taken, and the proper equipment and ground source heat exchanger was installed to match those, you would not have written this nor had a reason to ask the neighbors about the utility bills. Im confident the last two are the culprit to this homes issues, among ductwork, controls, and brine factors.

    Therefore I ask you kindly to re-title your article “An Inconvenient Truth About Ground Source Heat Pump Contractors”

    Please contact me any time to discuss this, and possibly help you rectify your situation with whats already been done. This is an unfair lashing to the GSHP Industry.

  66. Does anyone have thoughts about geo v. solar?

    I’m looking at renewables for my property. I believe the best alternative to paying for electric is to go solar. However, if I do that, does it even make sense to go geo as well?

    I’m looking for thoughts of combining geo/solar versus installing electric furnace/water heater and letting the solar take care of all of it.


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