[BabyPeanut]

$this->bbcode_second_pass_quote('Backpacker', 'I') work as an HVAC technician. There is one development we service that has geothermal. They work very nicely. Knowing Americans, though, they will wait until peak oil hits before they decide to go geothermal and then, of course, they will all want it done right now.

[Backpacker]

It is good that some are doing it now before the crunch hits but it is only a very tiny segment of the population. My company installs new heating systems and the ceveloppers will not even consider geothermal. They continue having us install gas and oil furnaces. When I speak to them about peak oil and how fossil fuel prices are going to continue skyrocketing they just laugh. They are not peak oil aware and are under this delusion that fossil fuels will last forever. It is going to take years to convert the majority of American homes to non-fossil fuel forms of heating. One problem is that it is so expensive but some state govts. are helping out. The state of New Hampshire offers a zero interest loan to homeowners to convert to geothermal, which is repaid over a reasonable time through your electric bill. People are notorious for waiting until the last minute. They wait till the last second then expect you to drop what you are doing, cancel your plans, and take care of them first. As peak oil hits it is going to be a gigantic bottleneck of this. I am not going to volunteer to answer the phones at that time.
FHP is a very good mfg. Their engineers will design the underground loop for you if you buy from them. Keep up with your plans. You will be fossil fuel free for you home heating before the crunch hits. If only more would think like that.

[BabyPeanut]

http://www.hannabery.com/hp101_2_pg3.shtml
$this->bbcode_second_pass_quote('', '[')b]Should I replace my system with a Geo-Thermal Heat Pump?
In most cases, our answer would be no. On paper they seem like a great idea but in the real world they tend to break down often and when they do, the repairs can be complicated and the bills tend to be much higher than a normal heat pump. A properly installed High efficiency air source Heat Pump combined with a high-efficiency air cleaner and central humidifier would be your best bet.

[nocar]

We have had a geothermal heat pump for over six years, very little trouble, and lots of savings on heat bills. It is quite common here in Sweden, and increasingly so.

But - we have all the things that is that speaks for it: Inexpensive electricity (here from hydro and nuclear), a stable granite bedrock, few very cold periods (it rarely goes below -5 C, but most of the year below +13) so we have long long periods when heating is necessary but not firing full blast.

When it goes below -5 the electricity usage skyrocks. I think this is the biggest drawback for it as general heating method - everyone will need lots of electricity at the same time. Get a wood heating system for such periods!.

Get a deep hole (more "heat" to be carried up, actually it is only +4 or so here), install large radiators (the heat pump is more efficient when heating a larger volume to a lower temp than a smaller volume to a higher temp). Our system is converted from a central oil burning system with water carried into radiators in each room. (the usual thing here) We did not have to change our radiators, which kept the cost down.

Newer systems can be used as cooling devices in summer, good idea as the ground get warmer ahead of winter. (No need for A/C here in Stockholm though)

With this system you get about three times as much energy heat from each energy unit of electricity. If your electricity comes from fossil fuels, you probably only get a third of the energy in the fuel to electric power, so in a sense it is not more efficient than burning the fossil fuel directly.
But you need fewer trucks to carry the fossil fuel or wood pellets (which really might be the best thing in Sweden)

So I would say - no trouble with the system, but not suitable for all locations!

Tell me about your situation

[BabyPeanut]

We get all kinds of temperatures here. Very wide variations during winter. 45F (7C) down to 10F (-12C) in 24 hours or less is not unheard of. We rarely have prolonged cold of worse than 20F (-6C) due to all the variation.

$this->bbcode_second_pass_quote('', 'W')hen it goes below -5 the electricity usage skyrocks.

[nocar]

Hi BabyP,

yes, we had an energy consultant/seller, with a smoothly organised system of different contractors. We just had to pay one bill as I remember, for different people drilling the hole; doing the plumbing work; installing the heat pump, taking away the old furnace. We went without heating for only one day. For us, they calculated the best return on the investment - the drilling of the 90 m deep hole (something like 10-20 cm diameter) was the biggest expense. And I think the calculation was correct from that point of view. Although for us the biggest motivation was environment, and I regret that we did not get a 120 m hole.
With a more powerful heat pump, we would also have to pay more in low demand periods.

However, with any heat pump system, when the demand is very high you have to use progressively more electric current. There is a temperature sensor outside which regulates the desidered temp of the heating water in the radiators, so when it is cold outside it has to work more. When it gets real cold, it heats the water directly with electricity - the heat pump can not cope. We knew that ahead of time. Of course the calculation was based on the low price for electricity that we have here (but it is higher now than 7 years ago). Lots of houses are heated with electricity directly.

We can afford the spikes of power use, it is the idea I do not like, and the fact that everyone will need huge amounts of electric power at the same time. Future problems, not today's.

Heat pumps are very effecient raising the temperature moderately, but have to use progressively more energy for achieving higher temps. That is the way it is.

We used to use about 3.5 cubicmeters of heating oil a year (space heating and hot water), that means about 35 000 kwh of energy. Also about 2000-1500 kwh of electricity for household use (cooking, freezer, laundry etc).
Now we use about 13 000 kwh a year, total. But some of the savings are due to decreased household size as the last child has left home.
We heat about 200 square meters - 160 sq m living space and then half the basement. When we first installed the system we did not heat the basement, but it was built for having a warm furnace, and problems with damp and mold appeared so we had to install extra radiators in the basement. Also the chimney needed an extra thing on top because it was no longer always warm.

We keep our house on the cool side, + 19 C, except when we have house guests. We also take short showers. Hubby grow up with strict training of turning lights out, so we turn out all unnecessary lights, in contrast to our neighbours.

One of our neighbours installed a heat pump system over 20 years ago when they first appeared. They were disappointed. Then the pumps got better and the sellers learnt to be realistic. Ours has worked as promised.

We looked into other systems as well, like wood pellets, but that would have meant more work, and a big storage space, and it looked to primitive for Hubby I think.

We have had a few little problems with the system, like every third year. I can not explain the problems because I do not understand them. The repair service has been free to now, but has required some repeated calls. Now they will start charging.

I will be happy to answer more questions.

[BabyPeanut]

$this->bbcode_second_pass_quote('nocar', 'I') will be happy to answer more questions.

[nocar]

Yes, you are right, it is moving water through the ground that carries the "heat".

It happens, very rarely, that the granite bedrock under a house is so solid that no water flows through it to warm the -3 C (or so) water and alcohol (for defrost) liquid that is returned into the hose in hole, which is then pumped back up at + 4 (or so). In that case the thing is a flop, or you have to drill in some other place.

Ground water is usually everywhere in hte ground. (It sounds like I am an expert but I am really think ground water is a mystery.) Anyway, for us the water table is only a couple meters below the surface - we would have preferred it lower, we have had flooding in the basement (it moves up and down). In wet weather we have water in the ditch by the street about 10 m from our front door - but this has nothing to do with our heat pump system. It is not all necessary to have surface moving water close by, for having a geothermal system.

BTW, is it really called "geothermal" in english ?- for me that sounds like vulcanic heat, like hot springs. We have nothing in the way of vulcanic heat, our granite bedrock belongs to most stable and oldest types of rocks there are on earth, but apparently with water flowing through cracks. Its "heat" comes from many years of summer sunshine - minus winter chill. Since the Ice Age I suppose. Here it is called "rock warmth".

I think "geothermal" heat pumps are a much better idea than heat pumps depending on outside air. At least the ground is not colder just when you need heat the most. There is a variety where you put the heat collecting hose horisontally instead of vertically - a bit cheaper to install but the drawbacks are: Digging up the whole garden when installing, accidentally hurting the hose/pipe when digging some years later, and the ground thaws some days later in the spring. NO WAY that I could take that - it thaws late enough for my gardening.

The simplest and best is apparently to put the hose/pipe into your gardenside lake - we just did not have one.


BabyP, What sort of ground do you have?

[BabyPeanut]

$this->bbcode_second_pass_quote('nocar', 'B')abyP, What sort of ground do you have?

[nocar]

BabyP, I guess I was more curious about what sort of ground you have beneath the surface, like from teh surface to 100 m (300 feet) down. But it there is a creek nearby I suppose there also is groundwater not to far down. For our system to work I think you need bedrock, not 300ft of sand if there is such a thing. I am not a geologist. But I feel very proud being experienced in a system that seems ultra modern for Americans.

[BabyPeanut]

$this->bbcode_second_pass_quote('nocar', 'B')abyP, I guess I was more curious about what sort of ground you have beneath the surface, like from teh surface to 100 m (300 feet) down. But it there is a creek nearby I suppose there also is groundwater not to far down. For our system to work I think you need bedrock, not 300ft of sand if there is such a thing. I am not a geologist. But I feel very proud being experienced in a system that seems ultra modern for Americans.

[BabyPeanut]

$this->bbcode_second_pass_quote('nocar', 'B')ut I feel very proud being experienced in a system that seems ultra modern for Americans.

[GoIllini]

$this->bbcode_second_pass_quote('Frank', 'I') believe that there are "challenges" to using geothermal directly unless you happen to live in one of those special places, but that indirect use (ex. extraction via heat pumps) could play a more significant role in the future.
For example, it's not uncommon to see electric heat in some places in Canada (I'm thinking Quebec and New Brunswick specifically) - one reason is their proximity to cheap hydro power. Electricity is cheap and abundant in these areas. If heat pumps were to be used instead, electricity usage would be reduced by a factor of (?) 3 or 4 and this would then be available to (a) offset generation elsewhere by coal or NG or (b) recharge electric vehicles (battery or Vd-redox cells). Either use would help offset fossil fuels.
Maybe my terminology isn't correct and I certainly don't have a good idea of how much potential there would be, but I've lived in Quebec and have been looking at houses in NB and 100% electric heat is quite common. I like the idea of using electricity to leverage what mother earth is already making available to us. After all the earth is the largest solar collector around.

[Graeme]

It is nice to see some positive replies about geothermal domestic heating.
But I take exception to the remark by Omar. It is a little like the early days of oil exploration. It takes sophisticated exploration (seismic) tools to find oil reservoirs. By analogy, geophysical resistivity techniques are used to find high-temperature (HT) geothermal resources. Geochemists sample spring water and determine deep reservoir temperatures. Geologists look in a suitable environments usually active volcanoes but I have found that (HT) geothermal resources also occur in Tertiary plutonic rocks fractured by major faults activated from the Pliocene in the Philippines. Similar environments may occur elsewhere around the Pacific rim or indeed the world, and I'm sure that these will be explored in future. We just have to search for geothermal "vents". You don't have to drill for them until you have carefully assessed the environment you are searching in.

[Devil]

If you are going to use heat pumps, you don't need geothermal heat. Any largish body of surface or ground water will be sufficient. As an example, the whole campus of the Swiss Federal Institute of Technology at Dorigny, near Lausanne, is heated in winter from heat pumps. As a guestimate, the floor area of the buildings, which are mostly 2 - 4 storeys, scattered over > 1 km², must be well over 1 km². This reversible system, using two-stage ammonia pumps, is also used for aircon in the summer. The "other end" consists of vast serpentines of pipework on the bottom of Lac Léman (Lake of Geneva), situated about 500 m from the pumps. In winter, the water temperature, at the bottom, is about 4°C, so be assured there is no geothermal heating.

I have not been able to obtain any figures as to efficiency etc. of this installation but informal conversations have led me to believe that it is economically less viable than conventional heating would have been, due to the enormous capital cost being amortised over 20 years and high maintenance costs. Notwithstanding, it is the subject of long term scientific studies, there being a department of energy at the Institute.
Geothermal heating, as such, is useful when no heat pump is required, ie when the water used can be heated to, say, 45°C or more, without the aid of a heat pump or additional energy (except for conventional pumps, of course).

So to partly answer my question, I read $this->bbcode_second_pass_quote('', 't')he six countries with the largest electric power capacity are: USA with 2 228 MWe is first, followed by Philippines (1 863 MWe); four countries (Mexico, Italy, Indonesia, Japan) had capacity (at end-1999) in the range of 550-750 MWe each. These six countries represent 86% of the world capacity and about the same percentage of the world output, amounting to around 45 000 GWhe.

[Graeme]

I really appreciate your comments, Devil, particulary those about heat pumps. You obviously took some time and effort to compile your reply. I do not want to at this stage research this topic in any detail but I can only appeal to the original article by Fridleifsson, i.e. there is considerable potential for geothermal to supply our energy needs in the future, but this depends on economics, environmental and social concerns. Geothermal development doesn't have to be near any major population centre. The electricity can be fed into a national grid. There is also another geothermal source that other correspondents have alluded to, known as hot dry rock. I have no expertise in this area but I would like to find more about it. Perhaps others have. . .

Graeme Scott

[Graeme]

I'm really pleased to see this post. It follows on from one that I initiated earlier:

http://www.peakoil.com/fortopic5779.html

I hope someone else can contribute to this thread on hdr, and/or heat pumps and high-temperature geothermal resources.

Graeme

[nocar]

well, I am no geologist, but I live in a heat-pump heated house. In Sweden electricity is relatively inexpensive (but increasing in price) and lots of houses are heated directly with electricity, to which a heat pump (saving about two-thirds of the electricity) is a great improvement. The heat pump installing business is currently very hot around here!
We have no volcanic activity in Sweden, so that energy source is ruled out.
But there was a lot of writing in the papers about a project in Lund, a university town in southerns Sweden, where they were drilling deep into the rock (kilometers) for the purpose of obtaining heat. Seems like HDR, doesn't it? Well, about a month (or two) ago I read that the project had been abandoned. They found no heat at the expected layer.

[Jamie]

After hearing and seeing alot of people still installing a conventional furnace, that burns fossil fuels, I started putting together some research. The question always seems to be why geothermal? My answer is now this...why not? I am new to our company (been here about 5 months now) so I am still learning geothermal. For personal enrichment, I started researching what I was learning, and I am quite impressed with the new technology, as well as the theory behind it.

I will start with this (and sorry for the book!)
What is geothermal technology?
Geothermal technology uses the earth's renewable energy, just below the surface, to heat or cool a home or other building, and to help provide hot water.

How does it work?
A few feet beneath the surface, the earth's temperature remains fairly constant-ranging from 45º or so in northern latitudes to about 70ºF in the deep south-year round. Geoexchange takes advantage of this constant temperature to provide extremely efficient heating and cooling. In winter, a water solution circulating through pipes buried in the ground absorbs heat from the earth and carries it into the home. The geoexchange system inside the home uses a heat pump to concentrate the earth's thermal energy and then to transfer it to air circulated through standard ductwork to fill the interior space with warmth.

In the summer, the process is reversed: heat is extracted from the air in the house and transferred through the heat pump to the ground loop piping. The water solution in the ground loop then carries the excess heat back to the earth. The only external energy needed for geoexchange is the small amount of electricity needed to operate the ground loop pump and fan.
What are the major benefits to the homeowner?
Homeowners enjoy lower utility bills (up to 70% lower than with conventional systems ), lower maintenance, and higher levels of comfort, year-round. Even more than that, though, they have the peace of mind of knowing they're being environmentally responsible.
Since a geoexchange system burns no fossil fuel to produce heat, it generates far fewer greenhouse gas emissions than a conventional furnace, and completely eliminates a potential source of poisonous carbon monoxide within the home. Even factoring in its share of the emissions from the power plant that produces electricity to operate the geoexchange system, total emissions are far lower than for conventional systems.

Can you be more specific about the environmental advantages?
According to data supplied by the U.S. Department of Energy and EPA, a typical 3-ton residential geoexchange system produces an average of about one pound less CO2 per hour of use than a conventional system. To put that in perspective, if just 100,000 homes converted to geoexchange, the country could reduce its CO2 emissions by 880,000,000 lb.
That would be the equivalent of converting about 58,700 cars to zero-emission vehicles, or planting more than 120,000 acres of trees. And the waste heat removed from the home's interior during the cooling season can be used to provide virtually free hot water-resulting in a total savings in hot water costs of about 30% annually, and lowering emissions even further.

Is geothermal used primarily in homes?
While many homes have been fitted with geoexchange systems, commercial enterprises, including factories, retail stores, office buildings and schools also use geoexchange to save energy and protect the environment. In fact, there are more than half a million installations in the United States today.
According to the U.S. EPA, schools are a particularly attractive place for the use of technology. Across the country, schools using geoexchange right now are saving an estimated $25,000,000 in energy costs-which can be used instead for better educational equipment and more teachers. These schools also save a half-billion pounds of CO2 emissions per year.

Should all of the nation's schools convert to geoexchange, the EPA has estimated that we could reduce oil imports by 61 million barrels annually, and provide the same environmental benefits as planting 8 million acres of trees or converting nearly 4 million cars to zero-emission vehicles.
If the same comparison were made across all commercial and residential segments, the potential for environmental benefit would be staggering.

What about a very hot or very cold climate-does geoexchange work in both?
Yes, geoexchange technology can be used in any part of the country. Why? Because it transfers heat to and from the earth, which remains at a relatively constant temperature, rather than the air, where temperatures can vary greatly.

Does geoexchange cost more?
That depends on how you measure cost. While they do cost more to install in homes than conventional systems, because of the ground loop piping, geoexchange systems typically have the lowest life-cycle cost of any heating and cooling system. Heating and cooling costs for a typical 2,000-sq.-ft. home can run as low as $1 a day.
Moreover, installation costs have declined substantially in recent years, and they're expected to continue to fall, as more builders and contractors offer Geoexchange systems, and as the industry develops innovative ways to install the systems faster and more efficiently. Heat pump life spans also DOUBLE on average over conventional furnaces, & they are almost maintenace free for about 20 years (other than filter changes). They are cleaner to operate as well.

Altogether, Geoexchange systems are a sound investment. The amount they save the homeowner every month in energy costs is more than enough to offset their higher installation cost.
Remember, too, that Geoexchange means extra savings on repair, maintenance, and hot water bills. And the energy efficiency of Geoexchange adds value to the home.
{edited to remove commercial solicitation by MQ}
*research above was gathered from:
The Geothermal Heat Pump Consortium is a nonprofit organization working to raise awareness and increase the use of geoexchange technology throughout the United States.

[nocar]

We (hubby and me) heat our house with geothermal and heat pump, been doing it for 6 years. I am all for it. We live in Stockholm, Sweden.
BUT there are serious drawbacks not mentioned above: It still uses eletricity. (Usually you get 3 units of heat energy from each unit of electric energy). If it gets very cold, you get less heat energy per unit of electric energy. And there is the serious problem of scalability. If everyone relies on heat pumps, when a cold snap hits, the electricity needs go skyhigh!
So it should really be combined with another heat source, for the very cold periods. Wood perhaps.
And if your electricity is produced by fossil fuels, you do not gain very much raw energy by using a heatpump and geothermal. (Well, you might need less trucks delivering fuel to houses. Reducing road traffic is always good)