Why do you want energy effecient? I just want to understand your goal.

bry911, that is a thought provoking question....there are a couple of obvious reasons, and I welcome your thoughts, because I may be misinformed and not knowledgeable enough.

First of all, from an environmental perspective, the renewable nature of geothermal is a benefit that doesn't compare to that of air source, so that is an issue that can't be ignored. But at what cost? The upfront cost seems high. And that is really the issue that I would like to hear about. Of course, I have not given a full run down of my specific situation, so this may be an issue that cannot be commented on.

There is also conflicting information on longevity of equipment, "comfort" of heating and cooling, installation and maintenance...all issues that have suggestions depending on which side of the geothermal fence you sit.

I happen to live in an area where it has been difficult to find trained and experienced installers. There are plenty who want to get more involved in geothermal, but I want someone who has the experience already, and not someone to learn on my project. Maintenance and upkeep become the problem if I stray too far from home.

"the renewable nature of geothermal is a benefit that doesn't compare to that of air source"

What is your definition of renewable energy? Geothermal uses the ground to gain and loose heat, a conventional heat pump uses the outside air. I don't see how one can be renewable and the other is not.

The cost is very high due to the excavation issues. Even after tax credits, you will never see a return on investment on a $128K geothermal system versus an air sourced heat pump. Even at $60K I would think from a financial perspective you would be better off installing a Carrier Greenspeed heat pump or a similar inverter type system.

I would take the money an invest it in 2X6 construction and spray foam insulation.

bethmgc, $128K is a tremendous amount of money. If you're set on geothermal, I would recommend reading more about the different types of installations available. There are some other forums out there that have a world of info, and some extremely knowledgeable and helpful installers. Project cost and expected running costs should be known before entering into a project of this scope.

Do you have access to more
detailed information regarding these ‘2-caves & a crevasse’, such as a 'drilling log'?

At what depth are they each found?
What is their height? Are they water filled? At what level is the water table? Has
steel casing been discussed? Are you planning on drilling water well? Have you
considered/discussed an open loop geothermal system if you are drilling a well
for domestic water usage?

Price ‘seems’ high. At that
price or less you might be able to drill a ‘Standing Column’ well for
geothermal. Is your driller just a geothermal driller/installer or a water well
driller/specialist that is also an accredited geothermal loop installer?

You might want to take any
documentation that you have already paid for and submit it to another driller.

I would just see this as a
technical challenge to overcome and not get too excited about it.

BTW: Solid rock is the easiest thing to drill through!

IMPO

SR

Unfortunately I do not have more information on the drilling at this time. This test well was drilled for a set cost, so that the driller could determine what the cost would be if we decided to continue on this geothermal path. He is used locally for drilling wells for the local geothermal installer (that our contractor plans to get an estimate from).

We will not need to drill for water.

I had hoped that the solid rock would be a benefit....we are wondering if we just need to select another area on the property to drill (~1.8 acres).

Thanks for the suggestions everyone.

There are so many important decisions to make during a house build....it is sometimes overwhelming to realize that I have to educate myself so thoroughly on an aspect of the build that can be quite confusing to the "regular" person (one with no prior knowledge of heating/cooling systems).

So when I asked about efficiency the thing I really wanted to know was, are you planning this from an environmental responsibility or a cost savings perspective. To be fair my answer to either of these things is to scrap the Geothermal altogether but for different reasons. Only in certain situations is geothermal really cost effective. You spend thousands more to see savings of a few hundred dollars. When, if you simply banked all the upgrade cost for a truly efficient home you would find yourself in a better financial position. Also, if you are going to use payback period to determine the cost effectiveness of an upgrade then you have to establish a max. For me I use 8 years at the moment (rule of 72 / 9%) but I am good with anything between 8 and 12. You can consider any money beyond that 8 to 12 year period as never getting paid back.

Now for the environment. If you want to protect the environment, install solar panels. They are much better for the environment than moving from an efficient heat pump to a more efficient geothermal heat pump. Again, they are not really cost effective, but they really do lower your environmental impact. Or you could build a smaller home. A lot of the rest is just lip service, if you want to make a difference then run some real numbers and make a difference. Don't get pulled into the "idea" of making a difference.

Forums are interesting. The written word is not heard, no inflection, so it is often hard to tell "intent"....for that reason, I will take the position that all advice offered here, to me, is well-intentioned.

I certainly know that I could build a smaller house. Or use solar panels. I know my responsibility to my environment. That I can "run some real numbers and make a difference", and not offer up "lip service".

My intent was simple. Ask if this was an outrageous cost estimate, given the details that I provided.

Thank you all for the offered help. I really do appreciate all opinions.

The details you provided leave a lot of questions unanswered. What type of equipment do you get for the $128k? Has a load calc been done? It's very difficult to say if the estimate is high, although it does seem to be. You also are eligible for the 30% federal tax credit. You seem to be very into geo, and I would like to see you make the best decision. I suggest you post your question on the geoexchange.org forum. Lots of folks willing to help there...

Edit - the above mentioned forum regulars are known to tell you when they think geothermal is NOT right for you as well.

Let me clarify my advice, a lot of consumers get pulled into energy efficiency today because it is oversold. People just assume that spending more money on their house to lower the monthly utilities is a good thing, and there is certainly nothing wrong with wanting to lower your impact, the problem is introduced by the fact that it is rarely better. I am not judging you for the size of house you are building, as the one I am building will be as large or larger when done.

Furthermore, I am not trying to be nice, nor was I really trying to be rude. I am typing some words to hopefully help you make a better decision. But spending $128k for geothermal is ridiculous. For that matter unless you live somewhere with high utility rates spending $60k is high. The geothermal estimate on my house was just under 40k and I will never even get close to getting my money out of it. I am still considering it, but for other reasons. Now since you are still considering $128k for geothermal I can only assume that you take environmental protection very seriously, seriously enough that I should suggest solar panels, serious enough that you will want to run the numbers for your impact.

My intent was simple. To tell you that spending $128k on geothermal for a house with the details you provided is outrageous, regardless of whether or not the estimate is inline with the norm in your area.

I do realize I am on a soapbox, and I realize I sound like an ass. Although, I grew up in the mechanical contracting world, I am an accounting and finance professor, and when I watch how even intelligent people spend their money a small part of just dies. I am not saying that you are going to spend your money badly, but more people are reading this thread than just you.

Do you have access to natural gas? I really wanted to go geothermal too, but we have natural gas, and according to people smarter than me (ha-ha), the payback didn't justify the added costs. Bry is saying the same things I thought when I read your post. I wanted to go geothermal because it sounded like the "right" thing to do. "Renewable" energy just has a nice sound to it. It ended up not being the right choice for me - and my estimate was less than half of what you are being quoted.

Thank you again, everyone. There is so much value in forums like this. You are right to point out that this public forum is read by others, and those people who take the time to read and post answers are to be commended. Over the years, I have personally learned a lot from those of you who share your knowledge.

As I said before, there is so much to be learned while building a house, and it is often daunting once you realize how much you really don't know about the whole process. And there is also fear when realizing the scope of this investment.

(Stickman42, thanks for the info on geoexchange.)

I think that geothermal may
still be possible for the project discussed in this thread at a reasonable price. I for one would like
to see the breakdown of numbers to separate the money involved in overcoming
the drilling problem encountered and to see what other ground loop solutions
might be implemented and at what cost.

This challenge might be
overcome at a much lower price than
quoted! I say this as an accredited specialist that does consulting for
drillers on difficult drilling situations as they relate to geothermal
projects.

Can a few simple questions
be answered? How deep (average) is the overburden (undisturbed earth) on the
property? At what depth was the first problem encountered; what was the exact nature
of that problem?

It’s unfortunate that all
the facts were not documented in a detailed, professional manner.

IMPO

SR

You didn't answer the natural gas question. If you will have natural gas, then it will probably be cheaper to heat the house with gas than a geothermal heat pump. It would also be more environmentally friendly to use natural gas if you get your electricity from a power plant that uses coal.

I am heading out to meet with the builder, and will hopefully get some of the questions answered.

Yes, we have access to natural gas.

Yes, coal is used at our power plant.

Don't forget about cooling.

My recommendation would be to get a 95%+ efficiency gas furnace. It would be cheaper to install and operate and cause less pollution than a geothermal system. An air sourced AC condenser won't be as efficient, but if you get the new high end types like the Carrier Greenspeed than the operating costs would be close.

It makes more sense to spend the money on additional insulation and better windows to reduce the energy requirements. Whatever decision you make, gather as many facts as you can so you can. Keep asking questions. It is the best way to learn.

I've always been somewhat annoyed by how the HVAC industry has misled the public and potential customers by corrupting the true meaning of the term "geothermal".

True renewable "geothermal" energy sources capture ground-emitted steam for interior heating and electricity production. We're talking about areas, typically seismically active, where the earth's magma heats water to the temperature of steam, and this energy is captured with turbines for electricity and heat exchangers for heating structures. Examples include The Geysers Power Plant in California and the many plants in Iceland. There are lots of other examples.

A "geothermal" heat pump is just that - a heat pump. It's not renewable and is no more geothermal than a bucket of water. In fact, even small bodies of water like a pond can be used for the so-called heat source. What can also be used as a heat source, at much lower installation cost, is air. These would be the standard air-source heat pumps that represent the overwhelming majority of heat pump installations.

It's always cheaper to heat using natural gas. Heat pumps are useful where electricity is inexpensive and/or natural gas isn't available.

Snidely is absolutely correct with regards to the way the term "geothermal" is used. It's been adopted as the layman's way of specifying a ground source heat pump (GSHP). I guess it's easier to say and sounds greener. The operating efficiencies are higher than air sourced, for the most part. Therein lies the interest. It's up to the individual to see through the glossy brochure and determine which technology is best for their situation.

Mike_home, I'm curious as how you propose that geothermal causes more pollution than a gas furnace. I don't have facts to support either side of this, but am interested in them if they exist. Do you mean the heavy equipment needed for drilling/trenching and the fuels used for power generation? I would think these would be countered by the environmental impact of natural gas exploration, drilling, fracking, etc... And you still need some of that same power to run the AC if gas is used for heating.

My own experience: former oil user for heat and DHW plus several window AC's. Switched to GSHP 2 years ago. After working through a terrible experience with installer, my HVAC costs today are 1/3 less than they were before. I also did a fair amount of air sealing and insulation work (I agree that money spent on tightening the envelope is the best bang for the buck), with still more to do. So far no service calls and comfort level is improved. No combustion inside was a plus for me as well.

Single story new construction with the opportunity to air seal/insulate to the max sounds like a great opportunity for any system to be right-sized and run as inexpensively as possible, whatever type of system that may be. I overpaid for mine, and wouldn't want someone else to do the same if I can help it. Even at 6500 sf, $128k is absurd. With GSHP, the right installer is paramount.

I imagine there is always room to improve on insulation and use better windows.

The walkout basement is ICF (concrete varies from 6-10", depending on the wall).

Windows are Eagle, low E argon, casements.

Main level, 2X6 ,, foam insulation.

roof, blown-in insulation (r-38).

Yes, we have natural gas at the home site.

The test well for the geothermal was 200'. First problem encountered at 5' (I dont know anything else about the specifics of the drilling).

The estimate to drill and grout the wells (needing 6 or 7) is for 45K.

The total estimate of 128K is to include the drilling and all equipment, ductwork, and labor.

This is not a firm estimate that I have in front of me. We will meet with this installer soon to see the estimate and get questions answered.

***Now let me say this.....truth be told.......I want a heating and air system that provides comfort....I am not looking for a "challenge", I don't want to take the system apart to get to "know" it in detail and figure out bugs and fixes. I want heat and I want cool. I don't want to see it on my walls, and I prefer to hear it minimally. There, I admit it.

I thank those who have offered suggestions, and I welcome more.

"I'm curious as how you propose that geothermal causes more pollution than a gas furnace"

A heat pump (geothermal or air sourced) uses electricity compared to a furnace which burns fossil fuel. It would seem a heat pump would be better for the environment than the furnace. However you should take into account how the electricity was produced to assess the overall impact to the environment. If the heat pump is powered by a coal fired electric plant, then in my opinion the gas furnace would be a greener option. If the power is coming from a hydroelectric plant or solar panels, then the heat pump wins easily.

mike_home: since this thread was semi-revived, I've been thinking in my spare time about it... Not to try and contradict you for the sake of contradiction, just looking to expand my knowledge.

I was on my electric co.'s website and found a source that said over 80% of the electricity used in my locale comes from a natural gas burning plant. That being so, it would seem unnecessary to burn gas to create electricity to move heat with a heat pump, when I can just burn gas at my home to create heat. Do you know if there's any way to compare the efficiency/green-ness of a natural gas burning electric power plant versus individuals burning their own gas?

If you and the power company are both burning gas then the greenness is about the same assuming the efficiencies work out to be the same. We don't know the efficiency of converting the energy in gas to electricity and the amount of losses transmitting the electricity to your house. We do know the COP rating of the heat pump but it changes as a function of temperature. Anytime you use the back up resistance heat then you are heating with electricity with all the losses I described above.

In summary the heat pump might be greener but not as much as you think.

Heating with gas is cheaper than operating a heat pump. This is true in the Northeast where electricity prices tend to be high.

I was installing. Geothermal systems in '78. All this time later I think there are better alternatives. I think it is great that you can get a 30% tax credit on geo, but frankly that is coming out of my hide. If you can get nat'l gas, do so. If not, in comparison to the cost of the geo, go with the highest efficiency heat pumps you can get. Look at the mini-split heat pumps. Carefully zone the building so you are not conditioning the whole place to comfort temp at all times.

Also, what I used to do was take a swimming pool and heat it with a glazed (higher temp) solar system. In the winter, use a good insulated pool cover. Let the pool water drive the water source HP. In the cooling season you reject heat to the atmosphere. If the cooling load is to high you may need to add a small cooling tower. These systems were pretty neat and worked well.

I found that most people would rather have a pool rather than a couple wells.

Re: the 30% credit - that's our government at work. Aren't solar panels eligible for the same credit? This discussion could go on forever.

Re: natural gas - what's important to the homeowner? Burning fossil fuels because it's cheaper or being flame free inside the house, especially when I have a bedroom very near the mechanical room? I do have gas service in my house already, but am glad I'm not using it for anything other than cooking

Re: mini-splits - glorified window shakers IMO. "Carefully zone the building so you are not conditioning the whole place to comfort temp at all times". 2 cooling seasons into my geo install and my costs for cooling the entire house without setback is less than when I used 4 window units in select rooms, and humidity is better controlled.

One size does not fit all, and as a consumer I'm glad to have options. Geo has it's pros and cons just like everything else. It just seems to get unwarranted condemnation. Get yourself the best installer you can no matter what system you choose, and you'll be better off for it. We're talking about comfort after all. How many people drive SUV's to get milk and bread? Couldn't it be done better with a Honda Civic?