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Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Sat. Feb. 21, 2009 11:10 am
by Cheetah
Freddy wrote:The latest ones using wells don't even use the water in the well. They drill the well, run a pipe down it & back up, then fill the well with grout (concrete). The only reason for the well it to exchange heat from the water in the pipe.
That would be a vertical loop closed system. They still make what is called an open loop system which takes water from one well, runs it through a heat exchanger, and injects it back into the ground through another well. Their big selling point is reduced installation cost. They can work but they can also have problems that make them more expensive in the long run.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Sat. Feb. 21, 2009 11:37 am
by Yanche
Cheetah wrote:
Freddy wrote:The latest ones using wells don't even use the water in the well. They drill the well, run a pipe down it & back up, then fill the well with grout (concrete). The only reason for the well it to exchange heat from the water in the pipe.
That would be a vertical loop closed system. They still make what is called an open loop system which takes water from one well, runs it through a heat exchanger, and injects it back into the ground through another well. Their big selling point is reduced installation cost. They can work but they can also have problems that make them more expensive in the long run.
Here in Maryland you would never get a permit for such a set up. It's a no no to put water back in the ground. Too many possibilities for some type of failure that would put contaminants in the return water, thereby polluting the ground water. A well driller will not drill a well without a permit.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Sat. Feb. 21, 2009 12:01 pm
by Cheetah
Yanche wrote:Here in Maryland you would never get a permit for such a set up. It's a no no to put water back in the ground. Too many possibilities for some type of failure that would put contaminants in the return water, thereby polluting the ground water. A well driller will not drill a well without a permit.
There are many places outside Maryland that do allow such a set up. I was not saying it was a good idea, just that it is done. After reading the horror stories about some open loop systems I would never consider having one.

http://apps1.eere.energy.gov/consumer/your_home/s ... opic=12650

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Sat. Feb. 21, 2009 8:49 pm
by gitrdonecoal
thank you thank you everyone for your input. it has really been usefull information. tell ya all, this site rocks! :band: . im goin over to the parents house tomorrow to show them all of your suggestions and keep ya all posted in what he decides. some guy stoped out this mourning and took some information from him. not so much as getting measurments and such for an estimate, but instead taking info of past fuel costs and such to show him how quick, or slow a payoff would be x ammount of years down the road. thanks all.
John

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Sun. Feb. 22, 2009 6:51 am
by Freddy
Cheetah wrote:They still make what is called an open loop system which takes water from one well, runs it through a heat exchanger, and injects it back into the ground
I have no idea why anyone would do that now. Once they discovered that a closed loop system not only works, but costs substantially less than drilling two wells, open systems stopped being used.

I might add... my buddy that bought the AHS coal boiler is a well driller. He looked long and hard at geothermal heat. He can drill wells for the cost of the fuel, yet he came to the conclusion that geothermal did not make financial sense. Of course in some other state where electricity is half the price of here, it could be a different story.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Sun. Feb. 22, 2009 1:28 pm
by Yanche
Freddy wrote: I have no idea why anyone would do that now. Once they discovered that a closed loop system not only works, but costs substantially less than drilling two wells, open systems stopped being used.
Well sourced heat pumps are used where there is not enough real estate for the ground coil. My county government just built a new library which uses multiple wells for the ground sourced heat pump. There was not enough area to install a ground coil even if they used the area under the parking lot. I talked to the design engineer and he said he didn't want to take the risk of having to dig up the parking lot to make a repair to a ground coil.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Mon. Feb. 23, 2009 9:47 pm
by arcticcatmatt
I have a coworker that installed geotherm in his house. Cost him 16k and he did all the work.

I am not impressed with its performance, at least for the winter numbers he shared with me. The only thing it is doing his semi-preheating his incoming water for his baseboards. He said (it was 20 outside on this day) that the incoming water temperature from the loop was 38 degrees. He then has a heat pump that heats it to push to the baseboards. That baby runs off and on at 7,000 watts!!

He showed me all of this online as his updates to the internet and he can check all stats at work. It even shows him his baseboard temps. Pretty neat. His electric bill was not pretty neat, it was over 3 times mine!

Doing the math.. it was a waste of money.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Tue. Feb. 24, 2009 4:08 am
by Freddy
Yanche wrote:Well sourced heat pumps are used where there is not enough real estate for the ground coil.
I wasn't talking well source vrs ground loop, I was talking open loop...two wells....vrs one well with grout. The two well system takes water from one well & returns it to the other. The grout system uses one well instead of two. The same water is used and re-used as in a ground coil, but there is no coil. It's just one pipe down the well and back up. No digging up larger areas, no spending money on two wells. Grouting is much, much less per foot then drilling.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Tue. Feb. 24, 2009 9:27 am
by steamup
I have seen both open well and vertical bore systems used.

I know of one person that used an open well system and was unhappy because it took too much electricity to pump the water out of the well. It takes more horsepower to pump water in an open well system. However, I know of a nursing home that uses geothermal that is sitting on an large aquafer. They went down 50 feet and could pump 1000 gpm out of the well. The run the water through a heat exchanger and re-inject it back into the ground 200 feet away from where they pump it out. That system works but does struggle under full load when it gets really cold out.

The vertical bore where the use closed loop piping inside the bore and grout the piping in place is more common as it is a closed loop. It takes less pumping horsepower and less maintenance. Also, you don't have to worry about hitting a poor producing well as with the open loop.

I know of another person that has a new 2000 sq. ft. house with a vertical bore system. He has (3) 375' deep bores with parallel piping back to a manifold in the house. Last I knew, he was happy with the system.

Geothermal has to looked at carefully to see if payback warrents the investement. Electrical rates must be low to make it cost effective. Don't even bother looking at it unless you have a very well insulated building. One of the advantages of geothermal is you have air conditioning also.

There are tree huggers out there that are all over geothermal because the think it is a "Green" system. Because most of our electricity comes from coal fired plants, I don't believe it is any more green than just burning coal directly to heat your house.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Tue. Feb. 24, 2009 8:11 pm
by coaledsweat
steamup wrote:They went down 50 feet and could pump 1000 gpm out of the well.
Do you mean 1000 GPH? 1000 an hour would be about 16.6 per minute, 1000 GPM would be a bit much from a well and would take about 40 HP to pump @ that rate. That might be about $80+ a day to run the pump depending on your KWH rates.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Wed. Feb. 25, 2009 3:42 pm
by steamup
Yes, 1000 gpm. Pumps on variable frequency drives. Large nursing home, commercial application, many heat pumps. The 10" dia. stainless steel well point screens cost $5,000 each. There were two supply wells and two injections wells. Mighty impressive flow.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Mon. Apr. 06, 2009 3:13 am
by geoTom
I just cant believe all the confusion on geothermal on this discussion. First or all I wana let everyone know I am in the geothermal field and have been working with it for 15yrs. I used to work for the biggest geothermal company in the Midwest. I serviced systems all day. The biggest problems I came across is people not installing and servicing these systems correctly. First of all geothermal is installed all over the place in canada Iceland and so forth. So anybody who says it don't work up north is wrong!! Also for the guy wanting to use a geothermal boiler. The guy you talked to at the home show doesnt know much about this. There is a new geothermal boiler that climate master came out with last year that produces 140 degree water. This is a awsome system and is being install a lot in eruop. If anybody would like some real answers on geothermal feel free to contact me. I know 1,000 of customers in the midwest and this includes chicago area, who have been using geothermal for awhile and are very happy with it. THe only people who are not happy with it are the ones who had a normal heating and cooling contractor put in this system and didnt know how to work on it. Please contact me with any ?'s @ **Broken Link(s) Removed** thank you Tom

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Mon. Apr. 06, 2009 4:33 am
by geoTom
Also I wanted to say that the pic @ the top of this blog is a slinky loop and I would never recommend someone using this method first of all its a lot of excavation and second of all the pipes run over each other cause the water to have a hard time bring ground temp back to the system. People usually do this type of system when they don't have room for a typical loop system. I warn you please don't have this done. Thank you TOm

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Sat. Apr. 11, 2009 1:01 pm
by dll
First of all geothermal is installed all over the place in canada Iceland and so forth.
From https://en.wikipedia.org/wiki/Geothermal_power_in_Iceland
“Because of the special geological situation in Iceland, the high concentration of volcanoes and geothermal energy are very often used for heating and production of electricity. It may be the same situation in the other places.”

For a cost per BTU analysis that includes geothermal for a northern state (New Hampshire) see:
http://nhclimateaudit.org/calculators.php
The calculations for fuel cost and efficiency, if known, can be adjusted for other areas.

Re: Geothermal Costs, Payback Time, Pros and Cons

Posted: Tue. Nov. 03, 2009 3:24 pm
by gitrdonecoal
my father just had a geo installed a month or two ago. so far he loves it, but has not needed the central air yet and it has not gotten very cold yet either. soon he will have some results. an HVAC friend of mine advised about to hike in electrical bills and high maintainence of parts, but went ahead with it. I suggested a stoker furnace lol