Geo-thermal

[walleyewizard]

Thinking about putting in a geo-thermal system for heating and air-conditioning. Anyone have any experience with these systems?

[Ryan Berger]

I would definatly check out other options first.

[walleyes12]

I have one in my house, works great, very efficient, and alot cheaper to run in the winter! Its very expensive to put in, so it will take a few years to pay itself off.

[fivebucks]

There was a pretty good and extensive thread on this in the last year. Try a search and see if you can find it.

[Hotspotter]

I have a buddy that installs for Hernke's Heating and Cooling in Cannon Falls. He's got me sold on them, of course, too late to put one in my own house. Alot depends on what cost you can get off-peak electric at, but for our local cooperative electric company, it'd pay for itself in the first few years. Esp. with the rate of propane rising more quickly than that of electric, I think I'd put one in my house had I to do it over again.

Joel

[DrKen]

I manage a mall where we have 7 geothermal units. And this spring I looked at putting one in my own home. Geo's are the absoulutely cheapest way to heat/cool a home but you have to figure the payback over more conventional methods. The larger your house or the leakier your house the more they make sense. If you have a relatively small house that is efficient you may not have any payback over a air source heat pump/ high efficiency furnace combination. Installation of a geo(water source heat pump) will cost between 12 and 17 thousand dollars. I went with a 95 percent furnace with 16 seer air source heat pump in a hybrid system. My figures showed that I could not recover the additional cost of a water source unit over the anticipated 20 year lifespan of the system. Your contractor can show you the costs of running each type of system and then you can do the math and make your decisions. One advantage of a hybrid system is that you can always run the furnace on a generator if there is a electric outage in the winter while most geo systems requre 40 amps at 220 volts so you would need 10000 watts minimum generator to run one. Practically speaking you would need a 13 kw generator or larger. Standard furnace will easily run on a 5 kw generator. So talk to your contractors and run the numbers. Good luck.

[Farmboy1]

When talking about payback time on the entire system, look into tax based incentives in the area you live in. Many municipalities will give additional tax breaks, or rebates when these systems are put in.

As a general contractor who is working on his LEED certification (Certified Green Buildings), I would go Geothermal if I were building a house.

[BoxMN]

Farmboy and others, I am building a small 1170 sq.ft. place now, with same sized unfinished walkout basement. Due to cost, I am just going high eff. furnace and 14 seer a/c, but also putting wirsbo in basement slab, and using the off peak electric. This is cabin, so not there all the time, so I don't think the geo would pay off for me. Does just the gas high eff. and the eletric boiler sound like a good solution to you? I am not even 100% sure I will get the boiler right away, but the more I think the more it would pay off to do it right away.

I am trying to do it right, but also keep costs down. My contractor is good, but always good to get other opinions

Thanks for info. We may live there someday, but not for at least 5 or more years yet.

[TRITC]

Our heating/cooling system (standard nat gas/forced air) is pushing 17 years old now and I have thought about going with geo for a replacement. Is it practical to go down this route? Are other people starting to retro-fit geo to existing homes?

[Barony]

TRITC- That is exactly what we are in the process of doing. Unfortunately, we have elec. baseboard heat w/ no forced air or ductwork (w/ a finished basement), so my cost is going to be quite a bit more. We're in the process of getting bids, but it looks like when the dust settles, it will be about $28,000. It's about $10,000 for the furnace and ducting, around $1,800-2,000 per vertical well (and we were told we needed 5 but I'm feeling that is 1 too many) and the rest is for the heat pump.

I've learned a lot about these systems over the past few months and feel it is the right way to go. There is a ton of info on the web and got a lot of solid info from the fine folks who contribute to this site. We're having a tough time finding people to dig the wells in S. MN though. My HVAC guy is new to the systems and hasn't been networked yet w/ many people who do this.

[jps]

I just watched a guy digging wells for a heat pump here in Sanborn, Iowa. Not sure where he was from, think maybe S.D. I could get his name and # if you like!! jps

[Ryan Berger]

Farmboy and others, I am building a small 1170 sq.ft. place now, with same sized unfinished walkout basement. Due to cost, I am just going high eff. furnace and 14 seer a/c, but also putting wirsbo in basement slab, and using the off peak electric. This is cabin, so not there all the time, so I don't think the geo would pay off for me. Does just the gas high eff. and the eletric boiler sound like a good solution to you? I am not even 100% sure I will get the boiler right away, but the more I think the more it would pay off to do it right away.

I am trying to do it right, but also keep costs down. My contractor is good, but always good to get other opinions

Thanks for info. We may live there someday, but not for at least 5 or more years yet.

If you have off peak available, go with a heat pump and a plenum heater. The heat pump- plenum heater combo is what we do for most people with off peak, and most call us thinking there is a problem when there natural gas furnace runs; saying it never ran last year is it supposed to be running? the combo handles most situations to about -10 degrees and with the infloor heat,, even better

[Barony]

JPS- I would appreciate that info. Email is rjbruns at mchsi.com. I may know who these guys are too because there was a crew from the Brookings area around here this spring putting some wells in.

Thanks!

[jps]

You should have an e-mail, Barony! jps

[DUCKJ]

We had our system put in 3 years ago when we built our home and man am I happy we did. We oppted to go with the elec plenum as back-up and it has only kicked in a few time when it got very cold. Our elec bill is a $200 ave for the year wich is a ton lower then it would be if we had to pay for oil or gas. It may cost a lot more to install but well worth it IMO.

Duck

[Justfishing]

Geo thermal saves energy but is costly. I would be sure I was going to be there a long time as it doesnt have much impact on resale.

In my opinion you need to start with a well insulated house with good windows or you are not getting the full benefit. 1st off the cost of each well is high and you want to reduce the number of wells. You will also be able to downsize the unit. The heat coming out of the register will seem cool compared to a gas furnace and recovery time is slow. For heating it will be harder to use a programable thermostat because of the slow recovery.

If you are building use something other than fiberglass insulation. Spray from is the best but costly. What can be done is use spray foam on the rim joist and cellouse everywere else. Cellulose with give better control of air leaks than fiberglass but not as good as foam.

Properly installed quality windows will also keep the air infiltration down.

A well insulated house it will be more comfortable and keep energy useage down for what ever systen you use. If you are retro fitting you want to upgrade the insulation and windows before sizing the heating and cooling system. To big of ac will not run long enough to dehumidify the house.

[beer batter]

Anybody have an estimate of what a geothermal well installation would cost for a 2000 sq foot home? Is there some sort of formula for how many wells are needed per square foot of home?

[pikechaser]

Here in MN a geo-thermal unit would be your best bet. (ground source) An air to air unit(heat pump) is not practical here..you'll be running on your back up heat most of the winter. too cold here in MN for a air to air unit