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There's so much interest into alternate forms of energy with the so called "oil shortage", but no one is mentioning Geothermal Energy. Why? Why aren't the The Electric Companies pushing Geothermal Heat Pumps? They are darn efficient, what are they hiding?
We signed our new house contract in January 2003 and because I knew our electric rates were going up in July 2006 by 72%, I made sure we would be getting a Geothermal System installed. Yes, we paid a premium, but considering the rate increase, we'll pay that off rather fast.
Anyway, our electric bills were very low. We told our friends and they couldn't believe how much we were paying for a 2200 sq ft. home with a heated basement. The vents were open in the basement because we have oak flooring and without heat down there our floors would be too cold to walk upon.
Only to say we put it into our new home too & LOVE it. Kept us warm all winter with ease and only about a $50 increase in our electric bill from our previous house - and at about 4x the sq footage.
We did open loop since we're pretty much floating on top of a rather large underground stream. (Weird to know, but nice for the geothermal system).
Like you, the up-front cost was a bit expensive, but I'd say we've probably recovered 1/4 or so of it back since we moved in in Aug. Well worth it since we're planning on staying in this house until my toddlers are through high school.
We have a Closed Loop System - it's also a DZ - Direct Exchange System. A pipe goes out from the Geothermal Heatpump in our basement to a manifold buried underground. Off the manifold there are eight loops going off in different directions down about 280', then coming back. One side is insulated, the other is not. In Heat Mode, the system picks up the heat from the ground in the uninsulated pipe and brings it into the house. In cooling mode, it's reversed - the freon goes out in the uninsulated pipe so it can dump the heat into the ground, then the cooled off freon goes into the insulated pipe where it comes back into the house.
Since it's a direct exchange system, there is only one transfer - freon in the heat pump. In a regular system, they use water in the underground pipes and there are two transfers - one between the water and the freon and one between the freon and the heat pump.
Our system also has the hot water unit DX Adapter. It's an adapter so during the summer every so often the system will reverse itself and use the Cooling Heat to heat the hot water. Basically giving us free hot water when it's in cooling mode.
We did have some problems last year with the A/C. Seems that with the drought we had the ground was too dry and the sand around our ground loops ended up acting as an insulater. This was causing the Freon to heat up too high. Because of that it was blowing the pressure valve on the unit when it was transferring over to the heating mode for the hot water. It was a big pain in the butt.
What the company had to do was install a drip line and a temperature switch so that when the Freon came back too high a temp from the ground, a drip line would turn on. This would drip water onto the manifold and down into each of the closed loop holes wetting the sand. This would allow the heat transfer to occur better. They also added a PVC Pipe for us to add water via a hose on top of the manifold. So if we see problems starting, I can take off the cap to this pipe and put a hose down it to ensure water gets down into the closed loop holes.
We have yet to test it all since they installed all this last October. But they said they'll guarantee it.
Anyway, here in Maryland our electric rates are going up 72% in July - and with our Geothermal System, we'll be sitting fine compared to our neighbors. And we'll earn back our outlays for this system that much quicker.
Yeah, we also have the hot water adapter on ours, but we haven't hooked it up yet. So many little projects not yet finished. We have on-demand water heaters, tho, so at least we're not wasting money heating a big tank of water. I was leery of the tankless, but now that I've tried them, I'm very happy with them.
Interesting about the problems with the closed loop system. We heard several warnings about open loop systems, but with so much ground water here & the extra expense of installing the closed loops, it just didn't make sense to us. I'm sorry you had the problems, but it's kind of nice to know that closed loop has its problems, too ;-)
With energy prices rising so quickly now, a lot of the decisions we made for this house are proving to be very nice! ;-) We scrimped in areas we could easily change later (paint, trim, countertops,etc) and spent our money on the expensive-now-but cost-saving-later things. Like the GS heat pump. We also have 6" outside walls and a combination of polurethane foam & blown cellulose insulation that has turned out to be very nice. I think we ended up with something like R21 in the walls & R40+ in the ceiling (R13 and R30 are recommended in our area) . Amazing the difference it makes in our monthly bills.
I'm excited to find this thread. My husband and I will be building a new house at some point during the next year or two, and I am convinced that geothermal is the way to go. We'll be living in a climate where it is quite cold in the winter, and hot and muggy in the summer, and where electrical costs are high. And we are sissies about feeling too hot, or too cold -- we like to feel comfortable, year-round!
We will have plenty of space to install the underground portion of the system, and I was wondering if anyone out there has experience with running the lines horizontally, just below the frost line, rather than in holes bored deep into the ground.
Another question: If we go ahead and dig a large pond (which would be at least 8 feet deep), would it make more sense to lay the lines just under the pond -- under the rubber liner -- rather than trenching or boring into the ground? Or, alternatively, to install the lines in the water at the bottom of the pond, above the liner? Or -- yet another possiblity -- to have an open-loop system, using our pond water, which would be guaranteed to be available at all times, and would be clean. It seems like using the pond in some way might be an economical way to do it, if we are already digging a hole anyway for a pond. Any ideas?
Using the pond water in the loop itself seems unreliable to me because you'd get uneven temperatures by the circulation within the pond. Not to mention the filtering issues with all the plant debris, fish, etc. There is an accepted method of looping the pipe around the bottom of the pond as long as the water is deep enough to prevent freezing. You can Google for more info - there's lots out there.
Running the line horizontally I believe, is more expensive than vertically, because of the additional digging required (I could be wrong - you can double-check that fact) but it might save on repair costs if they're ever needed (they wouldn't have to dig as deep to fix a problem).
If your site has any water under it, you can do open loop with the groundwater. You have to be sure that you have enough water to handle the size pump - for ours we needed 10 gals/min, if I remember correctly, and that's a fairly big size unit (our well does about 12-15 gpm w/o running dry, so we weren't too concerned - besides 'Poquoson' is an indian word meaning 'Great Marsh'...guess where our water table is :-) ). Problem is you have to have that even in the middle of a drought, otherwise you'll lose your AC just when you need it.
I don't know that much about the cost of vertical closed loop, but it is generally regarded as the most reliable option, I think. Mostly because it only needs a small hole & all the water you need is kept in the system.
Thank you, BackyardZoo. I can see why the vertical closed-loop system would be most reliable. I think the water table is not too deep, because there is a dug well (which can't be that deep) already on the land, and there is a marshy area at the bottom of our slope. But I guess we won't really know where the water table is until we go to have a well drilled for our domestic water needs. Which leads me to my next question: If we are already drilling a well, do we use the same hole for the geothermal system?
That depends on your water supply. As I said, you have to ALWAYS have enough water underground to handle the pretty significant supply needed by the heat pump.
For the open loop system, you will actually need 3 wells - 1 for water coming up & 2 to send water back down into. If the 2 'down' wells are placed so that the water can flow back to the 'up' well, then that will help some. But if you're siphoning off some of the water at the top to fill a tub or washing machine, etc, then you'll need a larger aquiduct under you to handle it.
It's probably cheaper to get an extra well (or 2?) dug while you have they guy out there then it would be to have to have him come BACK out. Our guy said he found water so shallowly on our land that he felt guilty charging us what he had quoted, so he dug us another well for free. We're getting ready to put a pump on that one so I can use that for irrigation instead of city water (Make friends with all your contractors - they can make you some deals ;-) )
Everything in open loop really depends on what kind of water can be found on your land. If you call a local well driller, they might be able to give you some ideas of what to expect based on what they've found around your area.
On another note - geothermal is still new/unusual enough that I had some difficulty finding a HVAC contractor to do it. Finally found a couple by finding the local supplier of the heat pumps online, then calling them to get a list of their contractor buyers. Kind of round-about, but I got tired of calling all the HVAC contractors in the yellow pages and hearing "geo-what?". Just thought I'd pass on the tip. ;-)
Yes -- it can be a hassle to be on the cutting edge! I once had a graywater septic system installed because I was trying to be environmentally conscious. It has been nothing but a headache -- not because there was anything wrong with the system, but because nobody knew what to do with it. I have heard that there is a geothermal expert in the area that we are moving to, so I will try to find him once we are there. No sense reinventing the wheel.
Thanks for all the advice. I am much preferring the closed-loop system -- I don't think I would want to rely on always having a steady supply of groundwater.
Definietly a concern. Like I said, we're all but floating around here, so we weren't worried and open loop had a cheaper install. But closed loop is probably the better choice for most areas.
You aroused my curiosity, though...now I'm going to have to go research graywater septic systems ;-) (not that I'll do anything with it - we have city sewer, but I'm curious now...)
You will find lots of information online about graywater systems (a.k.a. greywater, grey water, gray water). I think that in theory, they're great -- but in the case of my system, it was just too high-tech for the people who were in charge of installing and servicing it. There's a lot to be said for outhouses!
Hi I am on eastern long island, and had trouble finding a contractor who would install the geothermal system. I'm wondering if these systems work better in the warmer climates of Maryland and Virgina (probably Gazelle, Ca too). Any ideas? Also, when the one contractor had a well guy come, he said he couldn't get the right distance from the house, etc. on my land. What is the story on closed-loop systems? Would I then not need a well? I have electric heat and a wood stove, and for the past two winters (since I moved to this house) I've heated only with the wood stove except for the bedroom at night which I keep relatively cool and which is not near the wood stove. However, I'm aging and not in the best of health and worry that I won't be able to keep heating with wood so I'd love to get the geothermal installed. Thanks for any advice.
Hi, Beachcomber,
Most of my info just comes from a few articles I have read, and I'm sure other posters on this forum can help you more than I can with technical questions. But my understanding is that geothermal systems are just fine for cold climates. Once you get below the frost line (which varies depending on where you live), the earth is about the same temperature everywhere, all year. With a closed loop system, you fill the underground pipes just once; then the same liquid keeps recirculating constantly, picking up and dropping off heat as it makes its circuit. So with a closed-loop system, you don't need a constant source of fresh water (such as a well). But you do need to be able to install the underground piping for the system, which probably means a well driller would have to come and bore into the ground. Since the well driller isn't actually looking for water in this case, I'm not sure why it matters how far from the house the hole is.
I'm not sure about the distance, either. Our first well is only about 50 feet from the main house, about 20 if you measure from the (attached) garage, so I don't know how much space he was looking for. Could he have meant there wasn't enough space to get his drilling truck back to the spot? They are kind of big & heavy... (another, less kind, interpretation is that he didn't KNOW exactly what was needed for a geothermal system, but didn't want to admit it). I wouldn't think you'd want it so close that the settling weight of the house threatens to collapse the well, but that shouldn't be too far.
As for the latitude, I understand geothermal is very effective even in Alaska, so LI shouldn't be a problem. What MIGHT be a problem, however...isn't LI basically a huge slab of bedrock? The closed loop has to be either in water or dirt - I don't think rock will work. But I'd try calling a local dealer of geothermal systems and see if they can give some suggestions for other contractors (they won't be able to tell you if they're any good - just that they buy the systems for their clients - and maybe how long they've been doing so). Or call a few well guys on your own & get estimates. Most of the time an estimate is free.
Can anyone tell me were I can find all the nessesary information about installing geothermal system. I have moved to Latvia and live on a farm. My total electric supply form 3 phases is 10Kw. I have a mini escuvator that can dig up to 2 meters. I am know nothing about this system and am not looking forward to another winter were temp. gets as low as -30*C. I breed horses and have noticed that the pile of horse dung and old wood shavings steams with ehat for the entire winter. Would it be possible to use this instead of dinning many meters of trench in pot clay. There is plenty of wood. Would this not be a better option? I need advice.
Reading the past comments. I am still a beginner, but learn quick when it comes to saving $$$$.
Hi, William,
You're right -- your horses' manure has the ability to really take the edge off of those icy winter nights! A deep pile of it can generate enough heat to provide hot water for your household use, and even for an in-floor radiant heating system. Now, mind you -- I haven't yet had a chance to put these ideas into practice myself, but I have had the idea now for a long time to use horse manure to heat a greenhouse. Others have already done it. The idea is, you bury a long coil of hose in a big pile of manure. You fill the hose with water and connect a pump to it. The pump circulates the water through the hose, and the water picks up heat as it makes its way through the manure pile, and emerges from the manure pile at a temperature high enough to either use directly, as domestic hot water, or to circulate through your radiant floor tubing. I have in the past found some articles on the subject. I'll try to dig them out so you can read them, too. Hopefully they are available online so you can access them directly. I'm packing up to move, myself, so it might take me a couple of days to find this information and post it.
Of course, after a while the horse manure is fully decomposed and stops generating heat. But, since you have your own horses to supply you with "black gold," and an excavator to move it around, you can move the used-up manure away and move in a fresh pile from time to time. You would just have to be careful not to damage the tubing.
Since you have plenty of wood, you might be interested in the idea of building a masonry fireplace. The idea here is that stone (or brick, or cement -- any kind of masonry material) has a lot of thermal mass, meaning it can soak up large amounts of heat, and then release the heat back into your house gradually over a period of many hours. I have plans for such a fireplace, and if you are interested I could send you a copy. This info is not available online, as far as I know. Feel free to D-Mail me with your address if you would like the fireplace plans.
I'm also going to look for links to a couple of articles that explain geothermal systems. Again, I haven't done this myself, but these articles will explain the basic concepts. If you find a supplier for a geothermal system, the supplier should be able to help you do the system yourself. With your excavator, you could probably get down below the frost line and run your piping horizontally -- this would take a lot of space, but if you live on a farm, maybe you have enough space.
I'll get those links posted as soon as I find them!!
Here is a link to an article from Mother Earth News that tells about how they made a hot water heating system by burying coiled pipe in a pile of compost (manure and wood chips):
Have tried several ways to get this link to work, but no go. I think the page has been moved. I think I have the article printed out somewhere -- I'll try to find it.
Hannelore1. Thank you most sincerly for your reply. I am led to belive that my frost line is non existant at 1.5 meters deep. Also, I recall meet an Irishman in Liepja last year. Peter... He is involved in this system. I dug up buisness card. Eskimo heat pumps IRL Ltd. Please, this is not an advert for his buisness. Therefore I will contact him directly and see if he can offer advice. I will do the same. I have two email address. [e-mail:peterloughman@eircom.net] & [e-mail:eskimoheatpumps@eircom.net] Hannelore1 My email address is [e-mail:wtm2@inbox.lv] I have some info on my Blog. [HYPERLINK@www.williammullins.com] I have not updated this for ages so please do not use the link to send mail, as it will be send to my obsolete Irish email address.
now, first things first. Can you advise on the type of pipe I use underground on a horizontal system. The diameter and can it be agricultural black plastic pipe. Wall thickness and inside dia. Then the lenght to be installed. Even with my own escuvator, it is going to be a major task to dig the trench. but my life long dream is to have my own indoor swimming pool. 6 x 4 meters. Presently I live in verycomfortable accomodation above my stables. The old house is made and cladded in timber. I intend to remove the timber plank cladding and clad with old bricks, removed from the many old Russian structurs that litter the countryside. This year, my only task for the house is to make the pool, next top the house. Next year i will start to build around the pool.
Thgerefore, geothermal will be imperrative to heat the 36 000 litres of water.
Wow, William, sounds like you have some big projects planned!
I tried linking to your blog but got this message: "The server is temporarily unable to service your request due to the site owner reaching his/her bandwidth limit." Not sure what it means, but anyway I couldn't get there.
I'm sorry, I don't know the answers to your questions about the size and type of underground piping, or how long the circuit needs to be. My knowledge is very slight! Maybe somebody else on this thread can help you, and if not, then the supplier of the heat pump probably can.
I will be very interested to hear about how things go with your project. Be sure to post back here with your progress. Lots of pictures, too!
William, I finally found one of the other articles I was looking for. Our pesky cats had knocked it behind a dresser -- but since we are moving, therefore moving furniture, I found it! It is another article from Mother Earth News, and it has quite detailed info about how long and deep to make the trenches, what size and type of lines to use for various types of system, the differences between horizontal, vertical, and pond systems, and what the various systems should have cost in 2001, when the article was printed. Hope this helps:
Hannelor1 Many thanks once again. I have so much to learn and understand. It is the lodgic that is obvious! I will certanly keep yopu and any others who maybe interested, informed. But,,, be sure that this is not a weekend project. My blog is conjested with spam. Ireland has open internet. I got over 100 spam letters a day. Spam of real filth. I will ask my host to clean up and revive this. In any event. I think a photo is in order.. Brgds wm.
This is a little off of the subject you have and I just discovered it a couple of days ago so I'm just getting started and will keep you posted as I learn more.
I had a little burger place here, it's in the same building I live in, we closed it down due to the price of electric and gasoline. People out here make a choice between eating out and paying their energy bills, I lost. Anyway I moved a 3 door cooler out on to the porch in May and used it for storage. It faces the south catching the sun, it has 3 thermal glass doors on it. I walked past it the other day with the outside temp of 50 degrees and the thermometer inside had a top range of 130, it was shattered, I tried some of the other thermometers I had around here and they could not take the heat. I used to be in the refrigeration trade so I have some equipment around here to play with to investigate it further.
With my curiosity up I checked on it the next day from the time the sun first hit it to see how fast the temp. climbed. In less than 40 minutes it went from 42 to 135+ degrees.
The unit is only 5 foot tall and 7 foot wide not very obtrusive at all. It also comes with a built in heat exchanger and fans. I'll figure out a heat storage unit and all that and let you know how it all comes out.
P.S. I paid $200.00 for the cooler from 7/11 used.
With a little luck I might be able to build the whole thing for less than a $1000.00
I'm so glad I found this site. I'm going to install a ductless cooling system next year (I live in upstate BY). It gets quite cold here in the winter (below zero) and can get quite hot and humid in the summer (+90's+). I have a 12 year old Weil McClain Oil burner (150K BTU) with a new tankless oil fired tandem hot water heater. This is about as efficient a hot water system can be, but at 2.65-3 bucks a gallon for oil this winter, it will be expensive. I'm looking at Mitsubishi split systems, and trying to get info on geothermal units. I have a 280' well, no city water - urban environment. I plan to use my current oil-hot water system as a very low temp backup until I get the cash to finish the heating side of the system. I want the cooling part installed prior to next summer. We currently have hot water baseboard heaters, and taking them out and removing the current heating system is not in my first year budget.
Anyone have any experience with this and can suggest options? Also .. what are the best manufacturers for systems that can be locally maintained by traditional HVAC technicians?
First, if I'm reading you correctly, you may have a glitch in your plans - a geothermal system uses the SAME system for both heating & cooling, so you wouldn't be able to install the cooling part separate from the heating part - it's all or nothing.
But I would step through your phone book and call your local HVAC guys to see which ones are familiar with geothermal. I live in a fairly populous suburban area and I only found 3 companies that had even heard of the systems. They're getting more popular, however, so that has probably changed.
I checked out that last link provided and it said that those holes have to be dug 100-300 feet per ton of the unit. I have a 3 ton a/c, does that mean they would dig 900 feet? That sure does sound like a lot. I might strike oil if it went that deep. LOL
The issue is the amount of water - not the depth of the hole. So for us, we have very shallow wells - so much so that our well guy gave us a 'freebie' well, because he felt guilty that he didn't have to dig as deep as he had charged us for.
So, really, the depth of the well is going to depend on your geography and how deep you'd have to go to find water enough (consistently) to run the system. And then, the 'out' wells would have to be deep enough - or hit an underground stream big enough - to accept the same amount of water without it spouting back up out of the ground.
And then, there are the 'closed loop' systems as well, if you can't have the ground water requirements met in your area.
I installed my geo system open loop and water used for irrigation or to a pond. It works very well with average well water at 76 degrees. I also live on the coast so any outside appliance rusts out quickly due to the salt mist in the air. We run AC about 9-10 months out of the year. It cost with all items for hookup around $ 2,000.00 for 3.5 ton unit. Pretty simple install. Middle of summer electric runs about $150.00 and another 50 for well pump and shop with 1 Mercury Vapor. I also pump 3,600 gallons of water for irrigation. I figure I save about $ 200 a month. Geo's are better for AC than heating but are a bunch better at both considering the alternatives. Winter December through 1st of March electric runs $ 90.00
I installed a split unit A/C. It's an 18,000 BTU Carrier. Love it! Inside it's very very quiet even on high. You can sit at the dining table 6 feet from it and hold a calm converstaion.
Now... Looking into solar domestic hot water and geothermal for heat & cooling.
I just finished installation in pennsylvania. 3 ton climatemaster with a horizontal 4 pipe. also heats hot water. I installed the entire system using high density poly and fusion splicing the pipes. Have had it running two weeks now and it seems to be working great. maintaining a 45-52 degree entering water.
I need some advice. I am thinking of a low tec way to warm/cool my garage. Could I just drill 2 holes in the foundation, loop say a 6in line for a few hundred feet , and attach a fan to one end. It seems to me the air would be warmed/cooled to the ground temp. Any thoughts?
