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Geo Thermal heating - your eperience

Posted by woodbine_cat (My Page) on
Mon, Jul 12, 10 at 13:13

Hello we purchased a large house and would like to install geothermal heating. Presently the heating and cooling is heat pump. The house is located in Maryland.
I would like to hear from people who have geothermal heating, if they like it, how much energy saving they get, and if they should decide again would go again would go with geothermal?


Follow-Up Postings:

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RE: Geo Thermal heating - your eperience

I love my geothermal system. It's the best improvement I've made to our old house so far and I'm thrilled with it - to say the least. I have a WaterFurnace envision with closed loops and am on Long Island, NY.

It was started up the first week in January. Not only was my antique house warmer and more cosy than it had ever been with either oil or gas furnaces, I saved about $4000 in winter heating bills. I will probably save more next year when I use it for the entire season. Now that it's summer we have air conditioning and dehumidification which has made our lives far more comfortable. We'd had window units before. Plus, we have a desuperheater to preheat our water so we are getting savings on our hot water, too.

The unit itself is very quiet. It sounds a bit like a refrigerator running when it's on, but you have to listen for it to hear it. I used my same old ducts and the house is much quieter when the air is being blown through them. That's because geothermal runs for longer times at lower temperatures and at lower volumes than conventional HVAC systems.

Both my old gas and my old oil systems really were loud on start up and shut down, plus I could hear the air roaring out of the ducts when it was blowing air. Not so with geothermal. The ducts never shudder or rattle and the air coming out of the ducts is so quiet that more than once I have gone to the thermostat to see if it was actually on and even climbed up on beds twice to put my hand near the duct opening in the ceiling to see if it was even running. In each case the air was blowing out, but so softly and quietly that it was hard to notice.

I'd like to encourage you to go to two websites, www.geoexchange.org and www.greenbuildingtalk.com, to learn more about geothermal before plunging in, as I discovered that an awful lot of HVAC companies really do not know that much about it and there are a lot of slick salesmen. I met plenty.

If you do not get the right installer to design a system for your house you could end up with a system that does not work properly. Luckily someone with a good geo system told me he had learned about them through these sites before buying and urged me to do the same. It was the best advice I could have taken. I spent a lot of time educating myself and trying to understand what I needed to know to decide on the right installer, geoexchange, which is run by geo industry professionals, now has a helpful list of questions to ask installers which it didn't have last year when I was looking. Use it.

I highly recommend geothermal systems and would get another in a heart beat. Mine was expensive, but with a 30% federal tax credit, I could swing it. I also got $1000 back from my local power company, plus it gives me a lower rate for electric for six months of the heating season which is nice. Check to see what rebates or credits might be available to you from your local utility company, town, county and state, you may have some. When I added in my savings by not using oil, I realized my return on investment would be about 7 years, if the oil rates held steady, less it they went up. More important, I am no longer adding to our county's dependence on middle eastern oil for heating, and that feels great.

Good luck! I hope you decide to get a geothermal system. We are very happy with ours.


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RE: Geo Thermal heating - your eperience

Woodbine Cat, I dont have geothermal and no dog in this fight but I have researched geothermal and other alternative energy sources to the nth degree. The environmental folks and those making money in the alternative energy business hate my information but Ill debate the best of them (and I have) with facts and prove my information every time.

I have researched geothermal, wind and solar for many of my own projects and never was it a sound financial choice. If money is no object and you have the passion then go for it. We all spend money on things that are poor investments. I spent a ton on a backup generator system that barely gets used. It was a poor investment but its nice to have. If youre looking to geothermal or any other alternative energy source to save you money, then sorry to bring the bad news because its going to cost you more, not save.

Comparing apples to apples in tonnage, features, quality and knowledgeable installers, geothermal is going to cost you at least double the price of traditional HVAC systems. For my projects, it would take a 12 to 13 year payback and Im in your area of the country. If I financed those additional costs, the additional P&I payments would have been higher than the energy savings meaning there is no savings until the loan is paid off. Even with CD and other investment rates so low right now, these alternative energy sources are still an expense, not an investment.

Theres a good reason why these alternative energy sources have been around for decades (some much longer) and still only get installed less than 1% of the time. There is a good reason why almost no real estate investment owners install these systems on their investment properties. There is a good reason why most geothermal installers dont even install these systems on their own properties. The reason, its a poor financial decision.

I have spoken with 15 to 20 property owners around the country with geothermal. Most were new construction but some were replacing older systems and they averaged a 40% to 50% decrease in energy with the new geothermal. Two stated an increase in energy but I think they had poor designs and installations using less expensive equipment and HVAC contractors. There are very few good geothermal installers and they charge a premium even in this down market.

A 40% to 50% decrease in energy is good but I have replaced older systems with new heat pumps and got a 30% energy decrease just with newer equipment and efficiency ratings. If this is purely a financial choice, replace with a high efficiency system and insulate and seal your home as much as you can afford. This will be your best investment by far!!! Any honest geothermal installer will confirm my information.


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RE: Geo Thermal heating - your eperience

But, mepop, you have left out an enormous factor - the 30% Federal tax credit President Obama created to help move this country away its dependence on middle eastern oil and into alternative energies. It made my geothermal system competitive with the cost of fossil fuel systems I had priced.

Now that I have a geothermal system installed, I have saved $4000 over what I would have paid with an oil system last winter, and that wasn't even for the whole heating season. Plus, my hot water cost is partially off set by the desuperheater during the winter and entirely during the summer when the A/C is running.

Had I put in an oil or gas system I wouldn't have had that enormous saving and wouldn't be able to have a 7 year return on my investment. In fact, I would probably never be able to catch up with the installation cost of even the most efficient oil or gas system. Nor would I have such a comfortable house and such a quiet running system - geothermal has made a big difference. I've had a high efficiency gas system and it just didn't compare with geothermal comfort-wise, nor did my older oil system. Both would blow short bursts of super hot air which cooled down and left my house chilly many days, whereas the geothermal with its longer running times and lower temperatures seems to get its warmth into every nook and cranny where it stays longer. It's much better. My house was never chilly last winter which was such a pleasure and its lovely and cool now during the worst of the summer.

Geothermal is far and away more efficient than either oil or gas - it's been proven to be 400% more efficient. Just do some more reading about it and you will see I am correct. I didn't believe it at first, but I am a believer now. A well designed geothermal system is well worth the high upfront cost - and the short wait to take the 30% tax credit off Federal taxes. No more using oil or gas for me!


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RE: Geo Thermal heating - your eperience

I think that many people go with geothermal for reasons other than cost saving, i.e. environmental reasons. Also, present energy costs are no indication of future costs, which I believe will only increase as demand increases and supply becomes more limited or more costly to produce.
Remember that good insulation can go a long way toward conserving energy and lowering your heating or A/C costs, as well. Spending money on a geothermal system for a poorly insulated structure may not be the wisest investment.
My experience has been with a newly built, all electric (except for solar hot water), outrageously insulated 2400 sf house in central VA. Our summer highs routinely reach 90F+ and since you live in MD, then you are aware of the conditions during this past winter. Our electricity costs have ranged from $70-120/month, though we do supplement during the winter with a wood stove. Yes, the initial investment costs were high, and we may not live long enough to realize "pay back", but so far we are really pleased with the performance of the GT system and glad that we made that choice.


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RE: Geo Thermal heating - your eperience

I really didnt want to take this here Sunnyflies but its only fair people hear both sides. I never disputed the efficiency of geothermal. Installed properly, it works damn well. Many of your complaints from your old system would also have been resolved with a properly designed traditional HVAC system. Upgrading an old system to a newer, more efficient oil, natural gas or heat pump would have also brought significant savings but I agree, not as much as geothermal. My issue with geothermal is its not economically viable for the masses. Geothermal is an emotional, luxury purchase the majority of the time, not a purchase for saving money.

I calculated the rebates for all systems and still geothermal is not the most economical. Talk to any HVAC contractor, and theyll tell you that most of their business for all HVAC systems is currently being driven by tax rebates. This isnt just geothermal but all system upgrades have tax rebates but geo/solar/wind doesnt have any caps. There are also tax credits for energy-efficient doors, windows and insulation.

I have researched these systems, spoken to property owners, HVAC contractors, Engineers, Architects, gone to symposiums on alternative energy and even consulted accounting firms on numerous occasions for financial advice regarding these systems for commercial projects. I have been in the construction industry for a long time, purchased too many HVAC system to mention and gotten my hopes up for alternative energy many times only to be disappointed time and time again when the numbers come in.

The masses will never purchase geothermal due to the cost alone. The majority of Americans dont stay in their homes long enough (they move) to even get a payback on the investment. If you finance the additional costs, the finance charges exceed the energy savings. Many Americans who own their homes long enough to get a payback are older, kids to put through college, close to retirement or are retiring.

With all the factors needing to align for alternative energy to make since for an individual, only a very small percentage of the population will or can ever invest in it. With so few homeowners switching to alternative energies, the alternative energies will never influence a change on a scale that makes an impact.

"the 30% Federal tax credit President Obama created to help move this country away its dependence on middle eastern oil and into alternative energies." If only this were true? Im sorry but this tax and spend President only put in these tax breaks as payback to the environmentalists that helped him into office. Just as our government cant plug a simple hole in the Gulf or manage cash for clunkers, they cant do anything to change our energy demands and supplies except screw it up.

When the government put these high tax credits in place, it keeps installation costs high as the HVAC contractors have no incentive to lower their prices. It can be argued that these tax credits only keep the profits high for those in this industry and in the long run prevent lower prices which prevents mass acceptance. The only way we are going to change energy usage on a mass scale in this country is through technology, inventions and innovation, not the government.

Also our biggest importer of oil isnt from the Middle East. Our largest importer of oil comes from Canada and the second largest comes from Mexico. America gets as much oil from Venezuela as it does from Saudi Arabia. The Middle East only supplies us with about 20% +/- of our oil. We get as much oil from Canada as we do from all Middle East importers combined.

If this country really wanted to reduce our use of fossil fuels, the approach should be just the opposite of cost prohibitive alternative energy. Unfortunately, alternative energy in this country is all about money and politics when you come right down to it.

Coffeehaus, very few people make purchases to hedge the possibility of future higher prices. The Toyota Prius was being sold to hedge future high gas prices and those gas prices never went up to the levels that would have made the Prius an economical purchase. Prius and other hybrid sales have plummeted for this very reason. There are correlations to these electric cars and alternative energy for home owners such as geothermal.


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RE: Geo Thermal heating - your eperience

Mepop is looking at history and trying to predict the future economics of home comfort. Often this works, but sometimes it can fool you. Ironically, history can show us how this can happen.

Back in the 1970s, the US suddenly found itself faced with the OPEC embargo. Fuel prices increased rapidly and scarcities developed.

Not only did fuel prices rise. More importantly, auto drivers found themselves queueing up for hours to buy a few gallons of fuel, and wondered if they'd be able to get enough fuel to drive to work.

Fear and annoyance are powerful motivators! Demand for small, fuel-efficient vehicles leaped. Gas-guzzlng full size sedans sat on dealers' lots, and the dealers had waiting lists for small cars.

The Japanese automakers were far better prepared than American for this situation. This was mostly an accident of history; for decades they'd been making small, fuel-efficient cars for Asia and Europe, where fuel had always been more expensive than here.

Accidental or not, it was hugely beneficial for them. Look at what the US automakers offered to compete with their Toyota Corollas, Honda Civics, and Datsun B210s: Chevy Vegas, Ford Pintos, AMC Gremlins. (Chrysler imported Japanese cars and rebadged them.)

As mediocre as these cars were, Detroit couldn't build them fast enough to keep up with demand. They didn't really want to anyway, since they made far more profit on larger vehicles (and still do).

Toyota, Honda, and Nissan quickly established a market primacy in small cars, and indeed in cars in general, which has never faltered since.

Detroit, to their credit, temporarily wised up. For a while, they devoted more resources to small vehicles. This was the "downsizing" era. GM even founded an independent "small car company," Saturn.

But once the fuel prices eased and the filling station lines dissipated, buyers' interest in those smaller vehicles cooled off. Since short-term profit on trucks and SUVs was much higher, so did the US manufacturers' interest.

Detroit failed to learn from this lesson. Today, in spite of the lip service they pay to the idea, the US automakers are still mostly unprepared for $5 per gallon gasoline.

Now, suppose that instead of being unprepared in 1974, the automobile manufacturers had predicted the rush on fuel-efficient vehicles. Suppose that instead of satisfying their stockholders' demand for high immediate profits, they'd invested in the future, building small-car (or even electric-car) production facilities that they could have activated in a few days when demand materialized.

They could have sold more vehicles, and more buyers would have been satisfied. Japanese automakers might not have established the beachhead they did.

But they didn't, and they mostly still don't, because this quarter's profits are more important. I'm no economist, but I suspect this isn't just corporate shortsightedness, it's also a byproduct of public ownership of these companies - but let's not go there.

Instead, let's bring that lesson closer to the subject at hand. Several European nations - Denmark and Germany come to mind - have begun preparing for a world in which petroleum fuels are scarce and expensive. They've built up their alternative energy capacity over the last decade or so, when they had the means to do so. (The US could have done this too, but chose to spend its budget surplus from the late 1990s in other ways.)

Someday, when light sweet crude tops $200 per barrel, most likely the US won't have much choice but to pay it. Meanwhile, Europe will be drawing on the returns from their early-21st-century alt-energy capacity investment. Who then will be the world's superpower?

What can we learn on a personal level from this? If, like Mepop, you base your HVAC system payback predictions on history, you'll probably carry on just as you always have, using the same fuels you always have (but, one hopes, more efficiently).

That might indeed turn out to be the economically beneficial choice in the short term. However, let's remember that electricity is easier to make yourself on your own rooftop and back yard than are natural gas, heating oil, and gasoline. If you look to the future rather than to the past, to a day when traditional fossil fuels are expensive, scarce, or even unavailable - perhaps your forward-looking choices will be more like Coffee's and Sunny's than Mepop's.


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RE: Geo Thermal heating - your eperience

My goodness David, what a myopic vision. Just because Denmark and Germany does something doesnt mean we can afford it. If your neighbor buys a Mercedes or installs an in ground pool, does that mean you can afford the same? I dont think so!

Denmark and Germany dont spend over $700 Billion a year on Social Security. They dont spend $700 Billion on defense. They dont spend over $700 Billion on Medicare, Medicaid and CHIP programs. They dont spend $500 Billion on all the other welfare and assistance programs. They dont spend over $220 Billion on the interest for their national debt. BTW, our interest payments are skyrocketing mostly due to our current pace of government spending. Spending of money we dont have and can never pay back.

This is my entire point and thank you for emphasizing it. Its so easy for people to preach costly alternative energy when money is no object or when its someone elses money. Its all about the money David and thats why the only people spending on alternative energy are those who are passionate about it, can afford or someone else is paying for it.

This country doesnt have the ability anymore to produce the GDP we once did. We dont make anything as we did in the past. All the manufacturing is now overseas to more competitive markets. Our debt is not sustainable and a major crash is coming. Where is the money going to come from to transform to all this alternative energy? ITS NOT FREE!!!!

People just dont get it. The country is broke because we waste all our resources on so much political BS and nonproductive lifestyles. We have been on this track for many decades, its not just one administration or political party, its everyone going back to FDR.

All the previous administrations have been steering us towards a cliff. This administration is now keeping us in that direction, stepping on the accelerator and even boosting up the horsepower. This will guarantee we get over the cliff that much faster and slam back down to earth that much harder.

Well never have the money to revamp our energy infrastructure in your or my lifetime. Fossil fuels will supply this country and the world with the vast majority of its energy needs for a long time to come. Get used to it, live with it, stop whining about it.

We cant even pay to keep up our current infrastructure so the idea of revamping it to alternative energy is laughable. Expecting to do so is like expecting a 75 year old cancer patient, lying in a hospital bed to run a marathon. Aint gunna happen!

The only chance of America even beginning to revamp our energy infrastructure within the next half century is through private business, future inventions or technology, not the government. If homeowners want to spend on alternative energy, more power to them but the masses will never follow with the current choices.

Im sure as you do David, I believe solar is the answer for the future but with cheaper and safer manufacturing under future technologies. Before we even think about solar on a massive scale however, we better resolve the mass pollution problems from photovoltaic manufacturing.

Trading an energy problem with polluting the environment with massive amounts of heavy toxic metals such as lead, mercury and cadmium doesnt make a lot of sense. Mother earth can cleanse herself much faster from the byproducts of her own fossil fuels. Mother earth cant handle toxic metals in the same fashion and neither can human beings.

Thanks for the debate


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RE: Geo Thermal heating - your eperience

Sigh. This is not a political forum, and thus not the place to address the plethora of (mostly political) misinformation quoted above.

I will say, though, that I'm really saddened by the level of rage that's taken over this nation. It shuts out rational thought. This national polarization doesn't bode well for our future. Each side expends so much effort on tearing the other down that there's nothing left for actual constructive problem-solving.

I sincerely hope that you eventually find peace - and a sustainable path to the future that works for you, whether that's through petroleum or PV. The rest of us here are doing our best within our means. We are most assuredly not whining.


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RE: Geo Thermal heating - your eperience

Mepop Ive been following this thread, as you can well imagine, but havent weighed in because I (mostly) agree with you!

On another matter though, our geo is doing great. Here are the figures from the 2009/2010 heating season:

Location: Montreal Canada
Design Temperature: -7F
GSHP: Nordic DX-45 (3-1/2-ton) Direct Exchange
2800sq ft home
$475CND ($536 w/Tx) heating only
7568kW (366 days) heating only
~7.96/kW w/Tx & all charges (~2.21/kw of heat delivered w/COP 3.6)

Neighbors are paying for similar size homes $2k - ~$4k (heating only) depending on many factors (actual size, insulation, age of system, source of energy, attached/semi-detached, windows etc.)

Do I still recommend it? Yes, but not in every situation. Its a premium system at a premium price; you better have deep pockets and plan to be in your home for a long time.

Will you see a pay back?

That depends

SR


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RE: Geo Thermal heating - your eperience

David, you cant write 14 paragraphs how cars relate to energy then state I shouldnt post how politics and policy relate to energy. Hypocrisy Sir, hypocrisy.

Its funny how the rage in this country a few years ago was never complained about. My statements are not rage, just the truth as I see it. For the record, I have strong Libertarian beliefs and most Democrats and Republicans have screwed up the country. Both sides have their head up their butt if you ask me.

Nice to hear from you again Steve and I also agree with your post. Question, do you ever use geo for cooling in the summer? I know your summer weather is very moderate so Im curious if you ever installed for cooling?

Im going to an event in a few weeks and many will be there who are in this industry in some way shape or form. I plan on asking this question but Im curious what you think. I heard a complaint some months ago regarding a geothermal field losing efficiency because its just being used for heating.

I guess if the weather was cold enough, long enough through the year and heat was pulled out with no heat replaced, it could happen. Just wondering if you have seen this?

My apologies if I polluted your post woodbine_cat, I hope some information was useful.

Thanks,


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RE: Geo Thermal heating - your eperience

Re: Mepop

Our GSHP certainly does air-condition (as it is today). Weve had plenty of weather this July in the 90s and humid too! Most GSHPs both heat & cool, as well as produce DHW.

A properly designed borefield should not run into any trouble irrespective of how long and cold the winter is or conversely how hot (and dry) the summer is. This is easier to design in a residential application in that there are fewer boreholes to deal with but becomes more complex in a commercial, institutional or industrial site where the bore field is literally a field with a grid of perhaps dozens of boreholes on an x, y axis.

The effect is called Convergence of the thermal radii of influence. Simply put, the outer perimeter boreholes will behave differently from the center core of boreholes due to greater influence from surrounding boreholes being exerted on those nearest the center of the grid. This design challenge is dealt with by drilling an in-situ test borehole (that can later be used in the design), commercial design software and hiring professional geothermal engineers to model and design the bore field with predictions as to how the ground and borefield will behave and perform to at least 10-years out.

This is certainly beyond the scope of (most) residential geothermal applications. Suffice it to say that boreholes must be spaced beyond the thermal radii of influence of other boreholes, which in residential applications should be a minimum of 15-feet apart and 25-feet from the building envelope (foundation).

Our particular GSHP is able to detect if the ground is too dry, the on board computer can turn on an installed soaker hose that was install down hole along with the vertical ground loops to re-hydrate the boreholes if needed. However, our geology has a lot of fractures with rivers of water flowing through them and the boreholes as well. What that means when you have a Direct Exchange (DX) geothermal system is that the effect of the flowing water on the refrigerant is exponential as compared to conventional geothermal, as the refrigerant is circulated directly in the boreholes and separated from the ground (and water) only by the copper ground loops which are by nature highly conductive.

Conventional geothermal has HDPE plastic pipes in the boreholes that circulate a working fluid that is (should be) a mixture of water and anti-freeze. The point is that for active heating or cooling to take place in a HP (or air-conditioner, refrigerator or what have you) there has to be a phase change in the refrigerant (from a liquid to a gas or from a gas to a liquid, depending on the mode of operation). This happens directly in the ground with DX so the flowing ground water has an immediate effect on the phase change and is therefore exponential when compared to conventional geothermal.

The effect of ground water on conventional geothermal is only incremental, as the phase change of the refrigerant, which is located within a coaxial, coiled circuit in a secondary heat exchanger (liquid [from the boreholes]-to-refrigerant) that is located within the heat pump, inside the building envelope no direct exchange. DX GSHPs do not have this secondary heat exchanger. The ground itself performs this function through the extension of the refrigeration circuit, directly and continuously, from the compressor to the bottom of the boreholes through the copper ground loops. Consequently with a DX GSHP there are no HDPE plastic pipes, no water/antifreeze mixtures, no valves, no secondary heat exchangers and no circulating pumps to hookup, power or maintain - ever. The circulating of the refrigerant is done by the compressor of the HP which all HPs have anyways. Brilliant aye!

Back to air-conditioning. Geothermal can also be dual use simultaneously. A triple function geothermal heat pump (forced air heating & cooling, full capacity hot water and desuperheater for DHW), DX or conventional, can be used for 2-functions at the same time. Example, triple-function GSHP that uses its full capacity hot water production for in-floor radiant heating in winter can use the heat extracted from the envelope in summertime (A/C mode) and reject it to heat a swimming pool. Only a proper set of valves are (basically) needed to divert the water from the radiant in-floor heating to the pool (through a titanium heat exchanger). Rather than having 2-separate systems (i.e. A/C for the house & a pool heater), one integrated system can perform 2-functions simultaneously.

What happens to efficiency? The COP is effectively doubled! So a COP of about 4 can effectively become as high as COP 8! You calculate the effect on payback.

I wont go into detail but my 2-subspecialties in geothermal are drilling in near impossible situations and designing geothermal systems for heritage homes that have hydronic heating systems (large cast iron radiators) and converting them to geothermal using the existing radiator system, never having to install forced air ducts and ending up with central heating & cooling, thus preserving the heritage value of the property.

Got lots of money

Steve


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RE: Geo Thermal heating - your eperience

We are in the drilling part of converting to Geo thermal and I have a simple question, no politics involved. Can anyone tell me if the lime dust coming from the eight 150-200 ft deep holes will do damage t my perrenials, wildflowers and shrubs, mostly hydrangea? Suggestions and or advice needed! I am also worried about evergreens being damaged by the drilling and/or ruts from drilling rig. They are mostly
spruces, 25-50 ft tall? thanks!


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RE: Geo Thermal heating - your eperience

Ive heard different anecdotal stories of plants and trees dying. Honestly, Im not sure but have not personally encountered any horror stories. It cannot be good for your garden.

I would suggest what is only common sense. Gently hose off as much dust as possible, take a sample of the dust & cuttings to a garden center, and ask their opinion.

Some drill rigs are able to vacuum and collect most of the dust.

SR


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RE: Geo Thermal heating - your eperience

fsq4cw : " ... designing geothermal systems for heritage homes that have hydronic heating systems (large cast iron radiators) and converting them to geothermal using the existing radiator system, never having to install forced air ducts and ending up with central heating & cooling, thus preserving the heritage value of the property."

This sounds interesting. Can it be done with conventional geothermal HDPE pipes or do you use DX? Can the cold water running through the radiators really keep a house cool? What about controlling humidity?

I have a conventional geothermal in my own house which works beautifully. I just inherited a house with a radiator heat system, so I am curious. It would be great to use geothermal for this new house.


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RE: Geo Thermal heating - your eperience

The terms Liquid-to-Water, Liquid-to-Air, Water-to-Water, Water-to-Air, DX-to-Water, or DX-to-Air all mean that what is to the left of the to represents whats in the ground. The term to the right of the to indicates the distribution method within the house (usually, except for pool heating or snow melt in the case of hydronic distribution). DX, by the way, is ALWAYS closed loop. Water or liquid can be open or closed loop. Closed loop can be vertical, horizontal or pond loop. DX can be vertical, diagonal (off-axis), horizontal or even pond. Only Water can be opened loop. The term Liquid indicates that there is more than just water inside the loop, i.e. antifreeze. There should always be antifreeze inside all closed loops that may be even remotely subject to freezing this includes interior hydronic distribution loops as well!

Geothermal conversion of homes with hydronic heating can be done with any variety of ground loops including closed loop HDPE.

The concept is simple but expensive!

The existing cast iron or aluminum fin radiators are fed with warm water in the winter to heat the house. Additional low temperature fan coil units are strategically installed to supplement the heating due to a lower supply temperature of the water.

The additional fan coil units are reversible, as they both heat or cool. During the summer when cooling is required, chilled water is not supplied from the buffer tank to the existing radiator system but only to the new fan coil units. This is because only the fan coil units are designed to deal with condensate and thus dehumidify without introducing a new set of problems.

It is possible to configure such systems with either 1-buffer tank (heating or cooling) or 2-buffer tanks (simultaneous heating & cooling). Note that these buffer tanks are in addition to and separate from the buffer tank that should be installed with a desuperheater for heating domestic hot water. You may have up to 4-tanks or more, depending on the size and configuration of the system; 3-tanks would be a minimum for a properly designed system; 1-buffer tank for the hydronics, 1-buffer tank for the DHW and 1-active HW tank for the DHW.

Note than these types of systems are VERY flexible. One integrated system can provide heating and/or cooling, radiant in-floor heating, pool heating, full capacity hot water and snow melt. This means that in winter, the lady of the (country) house can walk wearing stilettos, from the helipad to inside the house in comfort; to the Ferrari jet set this is priceless!

Its very green. Did I mention its expensive?

SR


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RE: Geo Thermal heating - your eperience

"Denmark and Germany dont spend over $700 Billion a year on Social Security. They dont spend $700 Billion on defense. They dont spend over $700 Billion on Medicare, Medicaid and CHIP programs. They dont spend $500 Billion on all the other welfare and assistance programs. They dont spend over $220 Billion on the interest for their national debt. BTW, our interest payments are skyrocketing mostly due to our current pace of government spending. Spending of money we dont have and can never pay back. "

Germany and Denmark have a lot more money to spend per capita on state-funded health care, environmental programs, and welfare than we do because they don't throw as much money, per capita, as we do down the hole known as military spending. Our budget deficit for 2009 was $407 billion. Our military spending was $660 billion. If we had spent $200 billion, we still would have FAR surpassed China (they spent 98.8 billion) as the world's top military spender overall, and we would have had a $53 billion surplus. Other countries manage to fund these initiatives that improve their quality of life and energy independence because they make wiser decisions about what to spend their money on.

The 30% tax credit exists whether you like it or not. I'd rather we spend our money on harvesting clean energy in America than blowing up sand any day.


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RE: Geo Thermal heating - your eperience

I read with interest the post from the beginning about geothermal heating experiences.

Folks without experience and data shouldn't weigh in without the facts.

We have a very unique POV having engineered, designed and installed over 100 geothermal systems in four states. The facts are simple - in the real world there are geothermal systems delivering over 4.0 COP and 20 EER costing about 70% less to run than high efficiency fossil fuel systems.

Geothermal is one important solution to our addiction to fossil fuels - ANY fossil fuel. Cleaner coal or natural gas isn't clean, despite what the fossil fuel moguls would have you believe.

The trick to designing and installing geothermal systems is experience, experience, experience. Choose a contractor just as you would choose a heart surgeon - The more experiece the higher your confidence.

Geothermal properly installed is the best and most efficient heating, cooling and hot water systems available anywhere at any price

Here is a link that might be useful: Total Green


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RE: Geo Thermal heating - your eperience

Paul, are there any certification agencies for such contractors? Anything that a naive homeowner might look for suggesting that a particular contractor might be a better bet?

Or would one just have to hit Angie's List or something similar and hope for the best?

Thanks.


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RE: Geo Thermal heating - your eperience

Without any specifics, I would be weary of any numbers mentioned. The costs of fuel varies wildily around the country and year to year. I know people who pay 4.5 cents per kwh and people who pay 20+ cents per kwh, the others fuels have also had wide ranges. What is great in one area could be a poor decision in another.

My best advice is to have an energy audit done on your house and become vigilant in insulating your house and sealing drafts. After some high bills in 2005, I added insulation and fixed many leaks. I have a 2600 sqft house in an area with 6100 heating degrees days. I heat to 72 when we are home and drop it to 62 at night and during work. My heating costs for NG run about $500-600 a year (Nov-Apr). No matter how you cut it, there is not much room to obtain significant savings. I love the concept of GT, but there is no way to make financial sense in my case. During the coldest week of the year, lows around 0 and highs around 15, the heating demand at my house ran about 15,000 btu/hr

On a practical note, its hard to use a programmable thermostat with heat pumps, since they are slow to recover. So it is harder to benefit from being able to to turn it down during the night and work. Although, if your home 24 hrs a day a heat pump may offer advantages.


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RE: Geo Thermal heating - your eperience

Re: davidr

Check the link below for a contractor in your area.

After youve selected a geothermal heat pump, check with the manufacturer or distributor for a recommendation in your area. After contacting the contractor, ask for references.

SR

Here is a link that might be useful: IGSHPA, International Ground Source Heat Pump Association at Oklahoma State University


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RE: Geo Thermal heating - your eperience

References were key when I was looking for the right geothermal installer. I met plenty who offered to put a system in, but after talking with them I suspected that while they might believe in the technology, they didn't have a background that warranted my investing with them (yes, the systems are expensive, but as I discovered, after the rebate they were about the same as high quality fossil fuel systems.) When I did check references all too many turned out to be references from family, friends or business associates of the installer, rather than happy customers with no close connections. The company I eventually chose handed me a sheaf of papers with twenty years of geothermal references to choose from with the square footage of each house included along with the owner's contact information. I called people with houses of a similar size to mine and every person told me how pleased they were with their systems, even the guy who's system was 19 years old, so I knew I had found the right person. Now, I am recommending him to others.


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RE: Geo Thermal heating - your eperience

Re: sunnyflies

That's great!

Keep us posted...

SR


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RE: Geo Thermal heating - your eperience

I don't know if my response it too late, and I haven't read all the above replies because the posts are too lengthy and I don't have time right now, but thought I'd share our experience. We have geothermal that was installed when we built our home. We've had it for 3-1/2 years now. We live in Indiana, so we get cold winters and hot summers (probably not as cold as in MD, but hotter in summer). We've been very happy with our system -- no problems at all. Our electric bills run an average of 2430 kw/month for a 5000 sq. ft. home (for all electricity, not just the heating/cooling since I don't know how to break it out). In our area, that's an average of $180/month. The system cost $20,000 to install, but we recovered the difference between the cost to install a heat-pump within 3 years, plus the cost was built into our mortgage, so it was a no-brainer for us.

Good luck with your decision!


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RE: Geo Thermal heating - your eperience

Mepop said: "Denmark and Germany don�t spend over $700 Billion a year on Social Security. They don�t spend $700 Billion on defense. They don�t spend over $700 Billion on Medicare, Medicaid and CHIP programs. They don�t spend $500 Billion on all the other welfare and assistance programs. They don�t spend over $220 Billion on the interest for their national debt."

You're absolutely right about the military spending and, as far as I know, you're probably right about the debt spending. But um, you are aware, aren't you, that Germany and Denmark have universal healthcare, Social Security and excellent cradle-to-grave programs that work a lot better and help a lot more than our "welfare" system? They may not spend as much in raw dollars on those as we do, but that's because they're much smaller countries (80 million people for Germany and less than 6 million for Denmark, vs. 300 million for us). They spend plenty on that, but the payback is they consistently kick our butts in international measures of health and education. Oh, and they're far more energy-independent than we are. In other words, they send far less money to Osama bin Laden than we do.

And I'm not just spouting some liberal pipe-dream propaganda here, I've experienced their systems. I lived in Europe for almost a decade.


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RE: Geo Thermal heating - your eperience

Good Lord, thats an extreme myopic view there ideagirl! Denmark is a tiny country not much bigger than the small state of Maryland. I think thats what the other poster was stating that these countries dont have the burdens that America does and they can better afford spending in other areas such as alternative energy.

Your view point is a liberal pipe-dream and its not whats going on in Europe today. France is rioting, Greece is bankrupt, Germany is retracting from multiculturalism and Portugal and Spain are teetering next to Greece just to name a few. Within the next 2 to 3 years, government debt will be over 100% across all of Europe. Where have you been?

All of Europe is in a huge s#!t storm for their spending habits and self-righteous leadership of spending other peoples money for the power of a handful of individuals. The world can no long afford this liberal utopian pipe-dream where money grows on trees and nobody gets boo boos. That philosophy has caused a worldwide economical catastrophe.

There is no free lunch, everyone must earn their way in this world. If you want your pipe-dream, open up your own wallet and spend to your heats desire on these social disasters. Most liberals wont do that however, they just want to spend other peoples money.


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RE: Geo Thermal heating - your eperience

**Denmark is a tiny country not much bigger than the small state of Maryland. I think thats what the other poster was stating that these countries dont have the burdens that America does and they can better afford spending in other areas such as alternative energy.**

That's actually pretty much what I was saying. Denmark and Germany don't have the self-imposed burdens of spending billions fighting wars in Iraq and Afghanistan, for example, so they can afford to spend money on alternative energy--and universal health care, and so on.

The main thing I was responding to was Mepop's bizarre claim that they don't spend $X on Medicare, Medicaid and CHIP--that was a truly bizarre thing for Mepop to say, because they have universal healthcare in those countries.

You mentioned that France is rioting--well, France is "rioting" all the time. They have a tradition of "descending into the streets," as they call it, to protest absolutely anything and everything that bothers them. They would probably riot if the wrong person won on Dancing with the Stars. When I lived there, over a million people "descended into the streets" to protest the fact that college tuition had been raised by, I kid you not, $7 A YEAR. Yes, I said seven dollars. (Tuition is the same everywhere, and it was raised by $7 everywhere.) When asked why they would bother demonstrating for something so ridiculous, they said it was just the principle of the thing. The principle being, I guess, "tuition should not go up." In short, pay no attention to French "riots." They are largely meaningless.

Greece, Portugal and Spain have always been the poor cousins of the rest of the EU. They got special dispensations from EU-wide finance/budget laws and regulations, which was supposed to help them catch up, but Greece especially has failed to catch up. But those three countries were specifically identified in EU law as not being as advanced as the rest of the EU. They're not representative; they're the outliers who are, supposedly, trying to catch up. Anyway, my point is that what happens in those three countries isn't representative of the EU in general, and it can't be expected to be representative. They're all still experiencing some major growing pains, Greece especially, as they try to become normal EU countries.


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RE: Geo Thermal heating - your eperience

Forgive me if I don't weigh in on the political info above. Instead, I'll share our geo experience.

We live in Minneapolis, MN, in a 1950's rambler. Approx 1900 FSF on the main, with 1500 FSF in the basement. We had a 28 year old forced air furnace with a similarly old central air unit in the back yard. There was a disconnected fungus farm (humidifier) on the ducting, and the house was usually bone dry in the winter.

We were considering a GSHP when we learned of the 30% Federal tax credit, but then the installer we had picked (out of 4 who came and gave us bids), told us of a 35% State rebate (using Federal stimulus package funds), and we realized it was a no-brainer.

We spent about $35k for our system, including a Venmar 4100 Hepa ERV that I installed myself, a Honeywell Tru Steam 12 gal humidifier that I installed, a new 200 amp Siemens power panel, with a 100 amp sub panel for the dedicated heat pump only electrical meter), a new 95% efficient Lennox furnace (backup and air handler), a 4 ton 2 stage envision waterfurnace heat pump with de superheater and 55 gallon buffer tank (which I had to plumb in 55 copper fittings to sweat!), and 3 vertical wells 250 feet deep. The system is controlled by a Honeywell IAQ 8000 stat system.

Our costs, as stated were about 35k. We received a $9400 rebate check from the state (they didn't allow any rebate on the gas furnace part of the costs, as it wasn't GEO), a $600 rebate from our power company, and a $300 rebate from the gas company. We *should* see a full 30% tax credit on the full system cost when we do our taxes this year.

I hate math, so I'll use rough numbers--We should see around $20k in rebates, meaning we'll have around $15k out of pocket. A new conventional system would have cost somewhere between $10k-$15k for an identical high efficiency furnace and central air unit. Again, assume I could have found a contractor to install a conventional system for 10k (doubtful, IMHO), that means I paid a $5k premium for a ground source heat pump over a conventional system. Given that I'm only 40 years of age, and plan to stay in this house as long as I can, we'll see that $5k premium back fairly quickly.

According to the Waterfurnace calculations (which may well be optimistic), our averaged monthly utility bills should drop from $246 per month down to $64.

Obviously, the short payback on our system is possible largely as a result of govt subsidies. Much like the continued existence of many of our nation's banks and car makers.


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RE: Geo Thermal heating - your eperience

Okay - I'm risking more political "information", but I would like information from those you said the cost of installing geothermal was built into the mortgage.

I understand the value of insulating to create a sound and energy efficient home with the appropriately sized HVAC, windows, SIPs, etc; however, my interest in geothermal not related to those issues.

PLEASE - just information about the financing of a system for the small (1600 sq ft) home in which I intend to live until I die about 45ish years in the future.


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RE: Geo Thermal heating - your eperience

I built a new house last year and went with geothermal, but only after a lot of consideration. I believe it was the right decision in my instance, which was carefully thought out. AFTER the GT tax credit, and AFTER the rebate from the electric co-op; my GT system cost me approx $6k more than a high quality conventional system. I paid cash for the home. No mortgage, nothing. Obviously, that's not what usually happens.

In my estimates, the GT is saving me approx $1000-1500 per year. So my payback will happen in maybe 5 years. All in all, a good deal. Without the credits/rebates, not such a good deal, unless you are only interested in environmental causes.

Also, on the issue of GT being useful to lessen our dependence on foreign oil: I don't think that is the actual issue. Correct me if I am wrong, but I don't believe foreign oil is much of a factor in electrical production.
Geothermal systems save electricity, often produced by coal-fired plants, resulting in carbon emissions. Isn't this what we are trying to reduce?

I'm not trying to insult anyone, or be condescending, but just want to keep my facts straight.


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RE: Geo Thermal heating - your eperience

As an addendum: I've been thinking more about the foreign oil issue. I guess the heating oil used in some parts of the country could be tied to oil imports. Geothermal would sure be a good altermative to that.
In my area, natural gas is plentiful, so I forget about the heating oil.


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RE: Geo Thermal heating - your eperience

My husband and I are thinking about putting in a GSHP system. We are building a new house for retirement in East Texas. The size of the heated space is 1734sf....1/2 with 11' ceilings and the other with 8' ceilings, walls R-19 and attic R-38. Would I need a 3 or 4 ton, [3 or 4] bore holes, for the house?


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