We're doing it. I am not 100% sold as I don't think we've gained what I expected to gain with this on the current house - but this was a hill not worth dying on and hubby wanted it.

We ARE using units that are completely variable (pump, fan, compressor) and the lower the compressor runs the more efficient it gets - so that SHOULD help us. Our unit also produces domestic hot water, so it's pulling a bit of double duty.

We're currently "heating" the space with 2 1500 watt space heaters - so I am guessing all of this is overkill.

HVAC folks are there this week - starting in the shop.

Rebates not as good anymore and my state sucks now - but that it what it is.

I COULD have done air sourced heat pumps but don't want the big units or the noise, and I probably could have done mini-splits - but don't like the inside aesthetics OR the multiple outside units.

In a few months - I guess we'll see how it goes. LOL

I agree with @David Cary, spend the money on your envelope.

I am located in upstate NY and was quoted $50,000 (after substantial rebates!) for a geothermal system. The house is about 2,100 sqft. For around $15,000, we are able to install a Bosch BOVA heat pump with plenty of money left over to upgrade our envelope.

We have geothermal and like it. Your biggest expense is in the loop but they say those have a 100 year life span. We replaced our 17 yo unit last year. It was working OK but we’ll receive a 26% federal tax credit to offset the expense. Recent legislation extends that level into 2021 & 2022.

This was an interesting take on creating more of a commoditized solution for retrofitting. It has implications for new builds as well. It’s not there yet as “affordable“ for most of the country though. You pay up front for incremental monthly savings.

https://dandelionenergy.com/affordable-geothermal-this-old-house

If you can do it as part of an initial home build, it might be worth it. Otherwise, probably not cost effective. Remember, you basically have a heatpump (heat exchanger) and blower inside the house - you're just using the ground as a heat provider/heat sink instead of outside air.

To the OP:

Why do you want geothermal?

What are you hoping to achieve?

What type of distributions system are you considering and why, forced air or hydronic or both?

More details from you would be nice before offering any kind of informed opinion.

IMPO

SR

I built a new house about 8 years ago now, and looked into this back then. We are in NY and were eligible for the tax credits. However even with those I didn't believe we would ever even break even on the system. The pay back appeared to be so long that it didn't seem smart. However the key for me is we have access to relatively cheap natural gas - it may have changed the equation if we didn't have that.

I too agree with David Cary above. In my situation it was substantially cheaper to do what he advises.

We spent $21,000 on our geothermal retrofit 7 years ago for a 2400 sf house. 4 ton unit that supplements hot water. Our only alternatives were propane or oil. We've done zero maintenance other than filter changes. You need a big lawn for the loops. State and federal rebates were good then. I believe we've already reached payback.

"Our only alternatives were propane or oil."

Well, you had the option of electric (air-to-air heatpump), didn't you?

7 years ago (maybe it was 8) air-to-air heat pumps weren't being promoted as an alternative. They've come a long way since then.

Thanks everyone. Appreciate all the comments.

ditto what David said. I hate to say it, but allot of geo installers try to rip people off because it 'is' new and believe they can get away with it. It 'definitely' costs more upfront but 'should' be able to save money down the road depending how long you plan on living in that house. Also I would think (I'm not into evaluating house prices) folks that are...how much would this add to a house value? That could make a big difference. I know 'This Old House' show last week had a geo installed and it cost around 19k for around 2700sf house in the NE.. It also supplemented hot water. It was a rerun from a year ago. They had a new way to drill that was allot less expensive in a smaller area.(lot size).

Where geothermal and other high-efficiency systems shine is when they are installed in a home with an energy-inefficient shell (think drafty, poorly-insulated home with leaky windows) especially if that home is a climate zone with high or low temperatures over long periods of the year.

Geothermal systems are more complicated and more expensive to install than conventional systems. In new construction, the option to construct a more energy-efficient shell reduces the heating/cooling load over the life of the structure. Plus, it enhances occupant comfort. That's where I'd put my money.

I'm also struggling with this question. We are building a brand new home near Sacramento (El Dorado Hills). It's fairly large and I'm already dreading the heating and cooling costs. Our developer just came back to us and after "talking to their HVAC person who's been in business 30 years" said it's going to cost us over $100k just to drill the loops. He also went on about some nonsense about a special insulation for all of the plumbing so I think he may have gotten confused and thought we also wanted radiant? This obviously sounds wrong and I've called a few places that specialize in geothermal to talk to them myself. Curious if anyone in Northern California is willing to share what they paid or has any insight.

Watch the link to the This Old House segment on geothermal that JuneKnow posted above. They’ve managed to bring down the cost for drilling a vertical loop. Maybe your conditions are vastly different. I’d suggest a second opinion.

I know 'This Old House' show last week had a geo installed and it cost around 19k for around 2700sf house in the NE.. It also supplemented hot water. It was a rerun from a year ago. They had a new way to drill that was allot less expensive in a smaller area.(lot size)

I find this hard to believe. Perhaps this is the This Old House subsidized price.

Joshua, unless your new home is really huge, that sounds like an outrageous and excessive quote. I agree with the advice that no matter what HVAC equipment direction you go in, making sure that the build is tight (using today's modern techniques) and reasonably over-insulated will make a big difference.

A friend of mine built a large (7500 sq feet) house in a northern, western state in a beautiful rural area with winter snow and summer heat known for hunting, fishing and as a vacation or retreat spot for the well heeled from both coasts. While finding upscale building contractors for most trades wasn't a problem, the area's HVAC companies were apparently something less than impressive.

Because of limited choices, he went with geothermal but of the less expensive variety, an open loop system (so-called pump and dump). He got a good brand, I forget which one, I think maybe Water Furnace.

He's very satisfied with its heating and cooling performance but, as he mentioned a few days ago, the inside equipment is approaching middle age and little things here and there have started to fail. Maybe it's a function of the area he's in but even the HVAC people from the two nearest towns have limited experience with geothermal and he's tried the ones there and has started back at the top of the list to give ones previously discarded a second chance.

It's no less true for conventional HVAC equipment than for geothermal, the skill and integrity of the contractor matters far more than the brand label on the metal boxes. In the low Sierra foothills, you should be able to do well with air source heat pumps at a small fraction of the cost for geothermal

.

Thanks folks for the feedback. As expected, our developer is super confused about what Geothermal is and is SUPER resistent to it for reasons I don't understand and it's actually becoming a pretty big point of conflict.

That said, I did speak to the two companies that do Geo up here and it will be a pricey endeavor - we'll need between 7-10 bore holes at 300 feet each a a drilling cost of about $15 per foot since it's terrain with a lot of granite. They're doing the load calculations for us now in order to provide a proper quote. At the end of the day though, what matters is the delta between what is already budgeted for HVAC and the Geo system cost minus the 26% tax credit. Considering that many comprable homes can have PG&E bills of over $1000 in the winter, it still might make sense.

I take it you don't have room for horizontal loops? I have four trenches, each 100 ft. long, 6 ft. deep.

We are building into grade and something about only being allowed to trench to 8 feet when we need at least 10. Both companies said we have to drill.

Re: Joshua Brost

Your developer is resistant because this is a technology they’re not familiar with. The best advice for you is to take the HVAC completely off the table from your developer, do your own research and proceed independently. You will likely have a much better outcome at a lower price. You might not even choose geothermal in the final analysis and that would be OK because you thoughtfully went through the process and your decision will be better informed. You will install whatever is ultimately best for you without the mistakes of a developer that has an agenda that might not be the same as yours.

If you are interested in geothermal, contact a company like Waterfurnace and ask for a recommended installer for a Series 7 HP. You will be referred to their best installers as this is their most complex series to install. That doesn’t mean that you have to install a series 7 but you will be speaking to the most competent people.

You will ultimately choose what’s best for you and it doesn’t have to be geothermal. At least you will have the satisfaction that you have done your homework and that you’ve learnt from the process and gained experience.

Take a close look at the latest Cold Climate Air-Source HP’s as well to compare. If you really want to challenge yourself and have the time, investigate leading edge water (Hydronic) distribution for both heating and air-conditioning - that’s where the real comfort, zoning, energy efficiency and future is to be found. Forced air distribution and fossil fuels - including Natural Gas are rapidly moving off the table with newer, better technologies that are available today.

The key to everything is speaking to the ‘Right’ people; the greatest challenge is in finding them in the first place!

IMPO

SR

Interesting thread. 2 years ago a built a home and installed a DX geothermal system. It is 7000 square feet and costs 385 month for the electric bill which includes the running the geo and all other electric needs. It was costly but the tax credit took the sting out. I just sold my home and am currently building a new home. I am struggling mightily on what do for HVAC on the new build. Either air source or ground source geothermal??

I've learned lots along the way, but the more you know sometimes, the more confusing it gets. As has been stated numerous times, attack the home on the building envelope...tons of spray foam, even under the basement slab, get good windows(the ones that seem too expensive but pay dividends over time), and go over code wherever you can to help yourself in the long run. You should try and beat the blower door requirement by a good margin.

The new build will be a large one story ranch, with a large basement. I really want radiant heat, and was leaning towards the new air source heat pumps to provide the muscle. There are two that I found that are air to water, Arctic and Spacepak. There is little data out there indicating whether this is effective or not yet. The other weakness of these air source heat pumps are that they are ugly units outside in the rough elements, and they are somewhat noisy. Because of this Im leaning towards another ground source system, but would do a water based ground system this time. It is really nice not having any outside mechanicals with the ground source geo.

The most annoying part of wanting radiant heat with the geo is that I'd still have to have ductwork for the AC. This is beyond frustrating. I would love to not have ductwork. I know they say you can use the radiant floor pex system to act as a chiller in the summer, but I just can't comprehend how that could possibly be effective? I don't like the discreet small duct high velocity systems that are out there, as they are too noisy. I wish there was more on how well a new air to water air source heat pump could run cold water through the radiant floor to chill the house down and be the solution for AC.

"Open Loop and ‘Pump & Dump’, this is not always the cheapest method"

Every area and contractor are different. You learn from getting bids what differences there are among various choices. You fall in to the same trap sometimes, giving advice as if everyone lived in your Quebec climate. For my friend in an area with a much milder winter than where you live, it was considerably cheaper.

"I have friend that installed a geothermal system costing over $100k in a new 8000-square foot home that has 30-foot high windows, he says that his neighbours that have homes smaller than his are paying as much as $2400-per month in electricity for heating in their all-electric homes. My friend says his electric bills run a little over $200-per month wintertime - That’s a factor of 10 times less."

In that your friend likely overpaid by 3 X for the equipment he now has, consider that excess a prepayment for lower utility bills. He may or may not recover his prepayment.

"This is why a 4-ton forced air system requires a 1-HP blower motor and a hydronic system using a small pump for a large house only requires the power of 1-very small incandescent light bulb"

I think your explanation is misleading. The size of a motor depends on the amount of work it needs to do. A motor for a forced air system moving a large volume of air will of course be larger than a motor for a pump moving a small amount of water. Heating systems that use water sometimes don't even have pumps - it's a function of the physics of the approach, not because of a made up reason. I lived in such a place once for several years - an old oil burning boiler in a multi-story home with radiators. No pump. The boiler heated the water, it rose in the supply piping that went to the radiators and displaced cooler water that was returned down other pipes back to the boiler. It started slow from a cold start but kept a 3 bedroom home comfortably warm economically.

"Think Water - It’s the future."

Some would say it's the past. I suspect that air conditioning isn't so essential in your cold home area of Canada but for much of the US, air conditioning is essential and used for months on end. As a previous comment highlights, putting in radiant heat usually requires a duplication of systems because ducts are needed for AC. Most people don't have the money to put in two systems when one can suffice.

"Take a close look at the latest Cold Climate Air-Source HP’s as well to compare."

Do you think that's a good suggestion for someone who lives just to the east of Sacramento, California, where a cold winter day is when it doesn't get up to 50 deg F?

@just_janni, this is the only part of our geothermal unit visible outside the house. @Joshua Brost, this is all the “special insulation” required for my loop‘s plumbing as my 5 ton unit and flow center reside on the other side of the wall. The length of run parallel to the ground is about 12”.

No geothermal contractor should quote 10 fold savings. If they are, they are lying. The thermodynamics make a ground source heat pump generally more efficient than air source but not an order of magnitude more efficient.

I will always remember my energy report for our 4000 sqft house. It was a pre-construction report that listed savings for various upgrades. It was $200 a year for geothermal. That is $200 a year cheaper than conventional which was NG furnace and standard a/c. Now it was one report...

But in average US area, you might get 50% savings at the high end. Most of the time you probably won't get that much.

The real issue is this. The tax credit got extended but will expire. Then your installer is really going out of business. While service can be done by others, expect a small challenge (or a big one). Solar has gotten so cheap that drilling deep underground to get incremental efficiency improvements has an uncertain future.

My electric bills are zero. (OK - $400 a year with 2 EVs but the house is zeroed out). My PV system was cheaper than a geo unit. How many geo households have zero bills without solar?

Now I fully acknowledge that a more extreme climate gets a better benefit from Geothermal and the lack of outdoor units is attractive. But not worth the potential future maintenance concerns.

I agree, David Cary. The "savings" in many cases is no savings at all but a net cost. No return and often not even a recovery of the cost. Sometimes there are no reasonable alternatives because of location or setting, although the improvement of air source heat pumps is giving more competition to what has anyway been a too-expensive and only marginally attractive alternative of ground source heat pumps.

I'm a believer in solar panels and they can be used in much of the US. Sellers and installers can be scoundrels and often pricing varies with local utility rates. Lower prices where power is lower, higher where it's higher.

It's easy to see a positive return on solar panels. In my area, I've heard that installers advise leaving a small cushion of "need" from the power company so as to not install too much capacity. Although some homeowners want to zero out as a matter of principle and personal preference. That becomes reason enough without a dollars and cents benefit.

Re: taconichills

I’ll guess that if you’re in the States, your DX system was an Earthlinked, if in Canada it might have been either an Earthlinked or Nordic. For myself, I would not install a DX system for a 7000sq ft home. Not that it can’t work, I just wouldn’t.

“I've learned lots along the way, but the more you know sometimes, the more confusing it gets.”

That’s an indicator you haven’t ‘Drilled’ down far enough; you’re not yet at ‘Bedrock’, you’re still in the ‘Mud’.

“The new build will be a large one story ranch, with a large basement.”

Sounds perfect for in-floor radiant - especially if it’s Opened Concept.

I would suggest planning the layout of your basement - even if it’s not fully finished and renovated when built. Plan the basement room divisions for future use so that if you’re installing in-floor radiant, the piping can be installed when pouring the cement with zoning and future use in mind for both comfort & energy efficiency. Pay anything up front when building that takes you in the direction of zoning, comfort & energy efficiency. Same goes for basement slab insulation and isolation from the ground. It can all be rolled into a mortgage that will only have an incremental cost paid over time and that can have an immediate payback.

“The new build will be a large one story ranch, with a large basement. I really want radiant heat, and was leaning towards the new air source heat pumps to provide the muscle. There are two that I found that are air to water, Arctic and Spacepak. There is little data out there indicating whether this is effective or not yet.”

I have seen Strong data that this technology if highly effective and is proven in real world detailed analysis after at least 1-year of operation out in the field. There is another brand you haven’t mentioned, Nordic

“The most annoying part of wanting radiant heat with the geo is that I'd still have to have ductwork for the AC. This is beyond frustrating. I would love to not have ductwork. I know they say you can use the radiant floor pex system to act as a chiller in the summer, but I just can't comprehend how that could possibly be effective? I don't like the discreet small duct high velocity systems that are out there, as they are too noisy. I wish there was more on how well a new air to water air source heat pump could run cold water through the radiant floor to chill the house down and be the solution for AC.”

I would not recommend using in-floor radiant for cooling due to the complexity of having to monitor ‘Dew Point’ at all times and having to deal with that. You can go that route but I would suggest that if you do to hire a Professional Engineer that specializes in mechanical HVAC & Controls. If your home is more Open Concept you might be able to install Fan Coil units for both heating & cooling that would provide multiple functions.

Hydronic Fan Coils

That of Heating, Air-Conditioning, Dehumidification, Zoning and very importantly a rapid temperature response particularly in Heating Mode when you want raise the temperature faster than a Thermal Slab will allow for. Also keep in mind that the insulation break to ground and the depth of the radiant piping within the slab as well as the overall slab thickness, along with ‘on-centre spacing’ plays a very important roll in response to temperate change. This is even more important in the design of Municipal Garages, Fire Stations and Airplane Hangers where large door are opening & closing.

Re: EJF

I’m providing general technical information to anyone that comes across this thread requiring active heating & cooling. There’s no ‘trap’. We have the same pretty much equipment here as anywhere else. A compressor or a refrigerant or natural gas works the same way on both sides of the 49th Parallel. A specific model HP has the same installation manual whether you’re installing it in Quebec or California; ‘Best Practices’ for an installation are also most likely the same. The main difference is building codes.

Should someone in California install a ‘Cold Climate’ HP? Probably not unless they lived somewhere up in the mountains where it might be an advantage. There might also be an advantage to a Cold Climate HP once you drill down into the specs because you’re doing multifunctions simultaneously, that might be possible, I wouldn’t rule it out completely, every case is different.

“In that your friend likely overpaid by 3 X for the equipment he now has, consider that excess a prepayment for lower utility bills. He may or may not recover his prepayment.”

In my original post here I asked, “Why do you want geothermal?

What are you hoping to achieve?” Not everything is about money and installing the cheapest system. Some people have different motivations not to mention budgets.

Some people drive a Ford Focus and others want to drive a Tesla - and can!

"This is why a 4-ton forced air system requires a 1-HP blower motor and a hydronic system using a small pump for a large house only requires the power of 1-very small incandescent light bulb”

“I think your explanation is misleading. The size of a motor depends on the amount of work it needs to do. A motor for a forced air system moving a large volume of air will of course be larger than a motor for a pump moving a small amount of water.”

What if you don’t need a large motor?

There’s nothing misleading here; there’s no, “made up reason”. Water is the more efficient median for moving BTUs therefore it would make sense that a hydronic circulator would use less energy than a large blower. That’s also physics or else it wouldn’t work.

This is worth repeating:

"A given volume of water can absorb almost 3500 times a much heat as the same volume of air, when both undergo the same temperature change.”

3/4"tube = 20"x12" duct

3/4"tube = 18" ø duct

“Heating systems that use water sometimes don't even have pumps - it's a function of the physics of the approach, not because of a made up reason. I lived in such a place once for several years - an old oil burning boiler in a multi-story home with radiators. No pump. The boiler heated the water, it rose in the supply piping that went to the radiators and displaced cooler water that was returned down other pipes back to the boiler. It started slow from a cold start but kept a 3 bedroom home comfortably warm economically.”

I also at one time lived in a house that had such a gravity feed hydronic system. It was a marvel of technology of the day and was installed in the 1890s. Changes came with electrification and Bell & Gossett patenting their circulators in North America. That meant that boilers no longer had to be at the bottom of the stack and that smaller diameter pipe could be used, going out in any direction. Not to mention a faster response time.

What is old is New again, just like vinyl records never went away. Water is the future of residential space-conditioning.

Is the electric car also a relic of the past?

BTW: The climate in Quebec and most of Southern Canada can at times be some of the most extreme on the planet that can range from -40˚F to +100˚F; sometimes for days on end. I can just about guarantee you that without air-conditioning here the murder rate would triple! (…and the birth rate would drop)

RE: jrb451 (Fahrenheit 451?)

While it’s quite common to insulate refrigeration piping like this on Air-Source HPs, I do not consider this ‘Best Practices’ for geothermal. The runouts at the very least should be encased in a conduit that would protect the insulation and piping from molestation by animals, lawn mowers, vandals & UV. I would have specified something like this to be installed in each wall penetration:

Link-Seal

As the Coupling Bolts are tightened the modular sleeve compresses around the pipe to create a water-tight seal that can be easily released when necessary.

Re: David Cary

“No geothermal contractor should quote 10 fold savings. If they are, they are lying. The thermodynamics make a ground source heat pump generally more efficient than air source but not an order of magnitude more efficient.”

This was based on simple math via info provided from a friend during a phone conversation, $2400/mo ÷ $200/mo ﹦~10. Perhaps we can agree that the info is anecdotal; I believe it’s plausible.

In my previous post I divided the HVAC efficiency into 2-separate components, the ‘Source’ and the ‘Distribution’. Both should be looked at independently and each considered on their own merits. As safe bet for Geothermal COP would be a number between 3.5 & 4.

Regarding the distribution side of the equation, I have seen professional engineers calculate real world performance numbers where Hydronic distribution used only 1.8% of the energy that a 4-ton ECM blower would use. That’s a savings in distribution energy of 98.2% - I’ll take it!

I fully agree with you regarding tax credits and government rebates even more so. Why should my neighbour subsidize my ‘Premium’ Geothermal system?

I acknowledge that this site is geared more towards the homeowner that would just like to maintain what they have without getting skinned alive but there are also posters that are building new, large custom homes - on both sides of the border. Can’t we just step it up a bit?

Can’t we just acknowledge that some want the ‘Tesla’?

IMPO

SR

^^ We're the Tesla family. ;-)

Thanks for the links of that link-seal thing!

Re: Joshua Brost

I hadn’t noticed your posts and would like to comment on them.

“That said, I did speak to the two companies that do Geo up here and it will be a pricey endeavor - we'll need between 7-10 bore holes at 300 feet each a a drilling cost of about $15 per foot since it's terrain with a lot of granite.”

Correct me if I’m wrong. This sounds to me like a geothermal system of between 14 to 20-tons for a home that will be somewhere between as much as 8,400sq ft to 12,000sq ft if all this capacity will be placed within the envelope. That’s going to consume some serious energy no matter what you install, at design conditions.

BTW: Granite is the easiest thing to drill through; drillers ‘pray’ for granite. It’s ‘almost’ like a day of Ice Fishing for driller. It’s mud and clay that collapse inward and require casing in the Overburden down to the Bedrock where most of the challenges lie.

Re: Seabornman

“I take it you don't have room for horizontal loops?”

Re: Joshua Brost

“We are building into grade and something about only being allowed to trench to 8 feet when we need at least 10. Both companies said we have to drill.”

That sounds to me like the contractors won’t or ‘can’ trench deeper due to the risk of wall collapse injuring or killing their workers and they’re not set up to, won’t or can’t get permits to properly set up wall supports to prevent collapse or cave-in perhaps due to additional cost or insurance issues. This is just a guess.

Have you discussed loop design with regard to what might be possible on your property? Horizontal loops can have as many as 4-loops buried in 1-6ft deep trench with each loop separated by 12in of backfill. If space is an issue, has anyone mentioned Horizontal ‘Slinky’ type loops?

How about the possibility of open loop with 1-well as a source and another to return water into the same aquifer, depending on depth to water table and cost of pumping factored in. An other possibility would be a ‘Standing Column’ well (SCW). That last one is really the domain of Professional Engineers as there is a lot that can go wrong if not properly designed.

Due to the size and scope of this project I would suggest consulting with Professional Engineers (Mechanical, Geothermal ) experienced in all manor of geothermal drilling, installation, Modern Hydronic Design & Controls.

This is the best way to get a team that can implement what you want.

If your home is that big or anything close to it, the method of distribution will be critic to reducing operating costs. Consider in-floor radiant for heating that can deliver the Btu’s where you need them in the most efficient manor with small circulators. Conventional forced air might require as much a 3.75kW at Design Conditions - just for blowers and even with geothermal. Forced air also requires that you heat the full volume of air within the envelope. Low temperature in-floor radiant only requires heating about 6ft to 7ft above floor level , not the total volume. Radiant means lower temperatures at ceiling levels that also means lower ∆T between indoor ceiling level temperature and outdoor air temperature. That equals less heat loss.

Speak with professionals that know and understand what you want to do right out of the box - and can do it. They will likely be the ones that can take you on a tour of previous successful projects that might include Universities, Dorms, Libraries, Airport Terminals, High-end Condos and the like.

When speaking to P.E.s request data, operating spread sheets for completed, existing projects that demonstrate proven operating costs that reflect something close to or even better than projected costs during the design phase. If they’re the ‘Real Deal’ they’ll be glad to share that with you.

It’s the only way to bring down operating and maintenance costs to something manageable. If you’re building a really big home you have to take charge of the HVAC; there’s no long term successful formula for doing it low budget.

It’s ‘Go Big or go home’.

Think Geo - Think Hydronic Distribution - Heating and Cooling - Think Commercial P.E.!

IMPO

SR

I thought geothermal sounded cool but people about 0.3 miles away put one in and hit a methane bubble. We smelled it here for months and it was unbearable on their street. It’s finally gone away mostly. It took about 3 months. And I think interfered with hundreds of people’s enjoyment of their property.

that’s one risk to consider. the situation made the local paper

That has also happened in Ontario Canada and the province put a moratorium on geothermal drilling that all but killed that business there for quite a while.

@fsq4cw The house is 5900 SF, so not quite as big as your calculation but certainly bigger than anything I ever imagined I'd be building! lol.

It's in an HOA AND in a county with A LOT A LOT A LOT of crazy rules. Open systems are totally illegal due to the water waste (even though it goes right back into the aquifer) and frankly there are just too few people knowledgable here. The two companies here are the only game in town.

To top it off, our developer is being insane about this. We've been asking about HVAC since day one and he kept saying that there was plenty of time to deal with it - and now he doesn't want to deal with any changes which has caused a MUCH larger issue that we are navigating.

I'm still researching the possibility but am now thinking about dumping that budget into significantly increasing our rooftop solar and storage since the heat up here is much more of an issue than the cold. I know that doesn't offset our natural gas, but if I can more or less zero out the electric we are still in pretty good shape.

Re: Joshua Brost

I can’t imagine how they arrived at that size of a system - unless you were building a house - and a car wash!

IMPO

SR

With a new build properly done tight and insulated, a load calculation properly done shouldn't need suggest more than 6-8 tons, perhaps separated into 2 or 3 different units covering different parts of the house.

If you have natural gas, I'd keep it simple with furnaces and and straight AC. If not and you want heat pumps, then maybe air source heat pumps, propane furnaces in-line (they're not expensive) for use on only the coldest of winter days and an appropriately sized solar array on the roof. You get plenty of sunshine there and if you can bank summer production fed into the grid for winter use (ala PG+Eor other provider with an annual settle-up), you should be fine. With the blank stares you're getting concerning ground source heat pumps and little local expertise, I'd forget it. Too expensive of a risk to take.

Good luck

Am I the only one confused by this nomenclature? You all seem to be talking about ground source heat pumps, I always thought geothermal was what the folks who live in places like Iceland or Ouray have, where you can tap hot water coming out of the ground.

There are basically 2-types of Geothermal, high temperature steam and low temperature just below what would be the frost line of about 4-6ft Where the earth‘s temperature remains more constant year round.

Iceland has plenty of high temperature & pressure steam.

@fsq4cw,

The residents of Hot Springs, in my home state of VA, would be disappointed that you didn't include direct geothermal energy on the list. It's a quite nice experience to soak in a spring heated by the earth. Although I prefer doing that in Yellowstone....

"Am I the only one confused by this nomenclature? You all seem to be talking about ground source heat pumps,"

No, not at all. It's a corruption of a long standing term that means something different. It was an intentionally misleading term latched upon as a marketing ploy by the industry to try to appeal to people with higher levels of concern about the environment., etc. They haven't been successful, the market isn't growing in the way people involved in it had hoped.

The long term meaning of "geothermal" is indeed as in Iceland, where near surface underground volcanic activity allows wells that produce heat/hot water/steam used to provide indoor heating and electricity. Not too far from where I live, a geothermal power plant called The Geysers has been in operation for over 50 years. Hot water and steam are captured and used to produce electricity. At one time, it was one of the largest "power plants" in the state. Water is pumped back down into the ground to recharge the supply.

So-called "geothermal" HVAC systems are simply heat pumps. Air source heat pumps, the more common type, provide an HVAC source by taking heat from or transferring heat to (depending on the mode) the air. Geothermal heat pumps do the same thing. with buried or submerged loops in the ground. Heat pumps can reliably capture and so pump "heat" from even low levels of temperature. A heat pump can heat a home equally well from 45F deg air or 45F deg ground sources. An advantage of the ground source variety is for heating, the sub-surface ground doesn't get to cold and thus can continue to work when cold air temperatures would challenge an air source heat pump. But the advantage comes at a great cost.

I’m guessing (not really) that the advantage of a ground sourced heat pump is even more pronounced when trying to cool a house when the ambient air temperature is 95+ and the ground temperature is 55-60 or thereabouts.

I'm not an industry pro but I have a limited understanding.

Any heat pump, which a plain AC unit is a type of, pumps heat from one place to another. As explained to me, AC equipment doesn't bring cool inside as much as taking heat out. Warm indoor air passes by the indoor coil, raising the temperature of the coolant inside the coil. The coolant travels to the outside unit where the heat is released (put your hand in the airflow to sense that) and the coolant is cooled by being "condensed or compressed" back to a liquid and the cycle repeats. To heat, the same equipment needs a slight modification to run in the opposite direction, the outdoor unit functions like the indoor unit in AC mode, capturing heat from the outside, and the indoor coil functions like the outdoor unit in AC mode, releasing the heat to the indoor air passing by the heat exchanger in the air handler or coil. With a ground source system, "Heat" is either taken from or released to the ground, depending on which mode it's working in. In heating mode, so long as the temp of the air or the ground isn't very cold, there's heat to extract and pump to the indoors.

I welcome being corrected by anyone whose knowledge is greater than mine is. That's a lot of people, so thanks in advance.

Elmer, your explanation is good. The advantage is that it takes less energy to move heat than to create it; as much as 1/6. Benefits? should be cheaper to operate. Doesn't generate as much CO2 - none if the electricity source is not fossil fueled. Disadvantages - expensive to install, potentially noisy (all pumps generate noise), maybe more subject to breakdown than simply burning gas or oil.

The term "geothermal" hasn't been co-opted by marketing folks. It simply means "earth-heat." There are three ways in which geothermal energy is exploited: direct geothermal such as hot springs which were used in public baths back in early Roman times; geothermal heat pumps which use the earth as a large heat source/heat sink depending on the operating mode, and geothermal power systems which utilize steam produced in areas with volcanic activity.

As the contributor above noted, for consumers the term has always been confusing, ambiguous, and is suggestive of something that it's not. Misleading in a way that industry people I think were happy about and did nothing to clarify. A parallel moniker is not used, conventional air conditioning systems are described as having "cooling provided by ambient outdoor air" or "air powered" nor are their cousin heat pump models.

Not unlike calling the first Toyota Priuses that could take a charge from household current "Plug in" electric cars, despite the fact that the range of the plug in charge was something like 25 miles. and thereafter, it was gasoline powered.

Re: Elmer J Fudd

Could it be that you are a source of misinformation?

How long should someone remain confused about Geothermal after a quick search of the Internet, You-Tube videos, manufacturers’ web sites, Geothermal association websites, HVAC company websites and the like?

Look at the terms you use.

“It's a corruption of a long standing term that means something different.”

Isn’t language fluid, can there not be more than one definition for a word?

“So-called "geothermal" HVAC systems are simply heat pumps.”

Why are you so hostile to this technology?

“As the contributor above noted, for consumers the term has always been confusing, ambiguous, and is suggestive of something that it's not.”

Who says? “Always”? Really?

“Misleading in a way that industry people I think were happy about and did nothing to clarify.”

How do you know that; what are your sources for that statement? What percentage of people in this industry would you say are swindlers?

Is the Toyota Prius not sold as a ‘Hybrid’ or a ‘Plug-in Hybrid’?

What does ‘Hybrid’ mean?

Can you provide a link to a Toyota website that has a vehicle subsection called ‘Electric Cars’?

Too much nastiness and negativity, don’t you think?

IMPO

SR

Holy smokes, class is in session. I think we all just got educated, and in entertaining fashion. Well said fsq4cw!

"Too much nastiness and negativity, don’t you think?"

I could say in return why not ease up on the baloney and puffing more typical of what a potential customer has to listen to from an HVAC contractor during a sales call and instead offer propaganda-free insights that could be useful?

Where is the OP??

When we built our new house we planned to do geothermal. As the time approached we could never make the numbers work ...and we tried. Even assuming best case for maintenance costs the breakeven was too far out.

For us the $$$'s were much much better invested in reducing energy use - insulation, ACH sealing, better windows & doors. Now that we're in our home we're monitoring electrical use with an IoTaWatt and trying to reduce electric usage. We're also experimenting with various schemes of force air heat & hydronic.

Definitely with opaone on that!

Investment in insulation and air sealing has an ROI that beats any improvement in mechanical systems by miles. Not only that it has the potential to keep on paying back for a hundred years or more, so an opportunity to pay it forward. We looked hard at ground source heat pumps when we did an energy retrofit on our house and made a pretty large addition as efficiently as we could. With a heating bill that now runs a few hundred dollars a season (in MA, 3200 sf house) we could not pay back any significant fraction of the $40k-$60k extra it was going to cost in the lifetime of the system even if the energy cost were zero. In retrospect an air source heat pump may have been a better choice for us than the gas furnace.