Does anybody know anything about it? (Other than what can be found on Google).

Any body have it? If so what is the initial cost and what are your reviews of it?

I have a friend with an HVAC company in New Mexico that does a good amount of geothermal heat pumps. The sales manager mentioned that you can always spot the homes that have had one installed, there is always a service truck parked out front.

It's been a while since I was in the HVAC industry. On the surface, geothermal looks great, but when you factor in the high install cost and then the cost of repairs, you're probably not going to come out on the plus side.

I have a geothermal system with 3 loops under my property...about 1,200 ft.
AC is ice cold ...more efficient than conventional but heat isnt as hot. Fortunately we have a conventional system also. Long story....I will type on my laptop.

Think about $25 -$40k.... directional drilling to lay the pipe was expensive.

Interesting that they used directional drilling for that. I am a directional Driller.

Where are you located? What does your electric bill look like during the summer if you don't mind me asking?

Ok, you ready?

I'm in Northern California foothills where temperature can go up to 115 degrees yet it cools down to 50's and 60's at night. But my house is so well insulated during the peak heat season, the geothermal only kicked in twice in a month and the bill was $90. And I have 5,000 sq/ft where Geothermal heats and cools 2,000 sq/ft portion.

And I'm on PG&E where the electricity rate rages from 11 cents to 40+ cents per kw/hr depending on use.

My electric bill during winter at peak was $300+ because Geothermal kicked in a lot and it just doesn't blow as hot as our conventional unit using propane. I have a propane tank also.

Here's the story.

I bought a foreclosure last year with a house with a Geothermal unit...this house was built in 2005.

The unit didn't work and no HVAC expert in town could figure out why..

My house was a contractor's house who did the HVAC himself. I ended up calling him and he graciously came over and explained the system to me.

He laid hundreds and hundreds yards of 5 inch PVC pipes 8 ft below and decided to use "air" as the heat source for the heat pump.

Well..no such a thing exists...and he found out quick it didn't work after he did it. So he decided to fill the pipe loop with water...except it wasn't water tight so somewhere water leaked...so in order to get the system working..he would have to hook up a hose and running water.

Then again, the house was so well insulated, he rarely had to use it. But on the other side of the house we have a conventional unit that also gets rarely used.

But I ended up finding a Geothermal company who wen ahead and dug for 3 weeks to lay correct piping about 15 ft below the ground..1,200 ft worth then filled it with water and some coolant stuff.

When I check the rate of meter turn, the conventional unit and geothermal unit uses about the same amount of power...but geothermal cooling is ice cold. So in essence, I guess it's more efficient and doesn't have to run as often?

Again, heat is disappointing.

Other than having to redo the underground pipe, I haven't had issues and I'm not sure constant "repair" is true or not.

I like the system and do recommend it.

I do have the commercial grade FHP and the system looks simple enough to me but I'm by no means an expert.

If you do the drilling yourself I imagine you'll save a bunch of money.

And the duct system should be no different right? My understanding is the system itself is about $10 - $25K...

http://www.fhp-mfg.com/

Let me know if you have more questions.

Actually, the heat isn't that bad either. It blows at 103 degrees. It does work and since it's doesn't blow as hot, the air seems less dry and it's very comfortable.

It's just a subjective observation.

[This message has been edited by AggieDruggist89 (edited 4/13/2013 11:13a).]

My parents have it in their new home that sits around 1300 sq ft. All of their appliances are electric and their house sits at 78 24x7. In the past 2 years, there has only been 1 service issue and that was for a fan. The cool air is very cold and crisp and the warm air is dry. The blower runs quite a bit to keep the air temp stabilized which Im sure runs the bill up. Their monthly average is $180. and they really like the system. the drilling costs rsn them around $30k.

Much of it depends on where you live. I considered it on a new house we're planning in Savannah. Talked to one of the larger Carrier dealers here that installs geo. My take from that conversation was that geo works best in an area with wide seasonal temp swings. After a few months of dispensing heat underground the dirt around the piping is the same temperature and you lose the temp differential between the water in the system and the ground. At that point geo is no more efficient that a traditional heat pump. They would install one if I wanted it, but thought conventional makes more sense where I live. They are invested in geothermal enough that they have their own drilling equipment rather that sub out to shallow well companies, but their opinion on geothermal where I live was 'meh'.

I have designed large geothermal systems for commercial bldgs. All the above are good points, but all can be overcome.

Geo will work anywhere, but depending on the soil temp will determine how much piping you need to reject or extract heat from the soil.

A decent rule of thumb (but by no means exact) is that you will need one well 250 ft. deep at 20 ft. apart for each ton of AC or heating.

The most important thing is to design the correct length of well field. Vertical is more forgiving as you don't have to worry about soil temps close to the ground. Horizonatal or wells in lakes/ponds are more problematic.

Ground source heat pumps are a good energy savings idea, but they aren't the first thing I would do to save dollars.

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My parents have it in their new home that sits around 1300 sq ft. All of their appliances are electric and their house sits at 78 24x7. In the past 2 years, there has only been 1 service issue and that was for a fan. The cool air is very cold and crisp and the warm air is dry. The blower runs quite a bit to keep the air temp stabilized which Im sure runs the bill up. Their monthly average is $180. and they really like the system. the drilling costs rsn them around $30k.

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$180 for a new construction 1300 sq ft home seems insane and even worse with a $30k up front cost.

I have a 1500 sq ft house and my highest electric bill last summer was $160 and I have no gas appliances. I keep it at 75 when I'm home and 78 when I'm gone. So $180 seems high to me.

I'm in the industry. Geothermal isn't there yet. You'll never see the payback from initial installation and when (not if) you have an issue finding a qualified tech is very difficult. Prepare to wait and then over pay.

Seems high to me as well, but they keep the temp at 78 all day/night. The blower kicks on quite a bit to maintain the level. Since I pay the bills for them, its been $180 since they moved in. It IS lower than what it was before.

Geothermal overall is a quality system if you have the correct people guiding you and installing it. I have designed 6 systems for higher education facilities and water/wastewater treatment plants. PM me if you want more information.

All,

Thanks for your responses. The last few weeks I have been deigning my dream home in my head. I have just been trying to figure out if this would be one of the bells and whistles I would want.

I would be in the Abilene area. Hot summers, mild winters but with the ability to get cold.

I don't know if this changes anything, but I just thought I would add that.

Thanks again OB.

I have worked for Trane, Carrier, a design company and now I advise school districts on what to do with HVAC and electrical usage in general.

This question comes up all the time. I am in Houston and it does not work. Abilene will be a little better.

For the Geothermal system to work properly through its whole life it must have roughly the same amount of heating and cooling days. You are using the ground as a massive heat sink because you are putting the heat in the ground during the summer and taking it out in the winter. In Texas it is roughly 9 months of cooling and 3 months of heating. Because it is not balanced you are sending more heat into the ground than taken out. Eventually the ground will reach a steady state of around 95 degrees (in the Houston area) and will basically be equal to an air cooled unit. Abilene will be better but not good at this since it has the cooled winters. The best areas in the country for this are Tennessee , Kentucky, Missouri, Maryland, Virginia.
Things can be done to delay this steady state like more holes (bigger heat sink) but the payback will not be good.
The other point Texas has problems with is our ground. I have forgotten the component but something is in the ground that is not a good heat transfer material and blocks the transfer of heat (in the Houston area). You will have to ask locals if it is good in Abilene.

Bottom line, the paybacks are not there. People selling geothermal site examples that are either up north or just the first couple of years (before the steady state is reached and paybacks drop off).

I did a study on a $7Million house in the Woodlands. 21 SEER Geothermal came out the worst on life cycle costs. Spring ISD is not seeing the returns on their system they installed for a LEED project.

If you want something above normal efficiencies go with a dual stage unit. Most houses will only run on one to two tons of AC.

My $0.02

On a somewhat similar topic:

My pool heater and A/C condensing unit sit next to one another on the side of the house and I often see them both running simultaneously. A steady stream of energy expense flowing out of my wallet to cool the house and heat the pool at the exact same time.

Anybody ever heard of someone using a heat exchanger to cool house/heat pool at the same time?

2x6 framing, R-eleventy billion insulation, super efficient windows, dual stage compressor, gas heat.

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Anybody ever heard of someone using a heat exchanger to cool house/heat pool at the same time?

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I know an HVAC contractor in Amarillo that tried to make one. I don't think it worked well.

Would an open loop system solve the problem of uneven heating days? Assuming you were able to drill multiple wells on the property. Would it still be more cost effective to just get a conventional AC unit, and spend the extra money on a solar array?

With an open loop system you'd have to have something like a cooling pond you see at power plants.

Viable? Sure. But not in the same universe as cost effective.

First money I'd spend is on super-insulating your house, make it airtight, install air heat exchanger.

PV array is a good idea too. It is like paying for your electric costs for 15-20 years upfront, but a better investment than bank CD's.

Goose, I am installing a pool and thinking of building one as a demo. Basically, to get a write off on my pool as a work expense.

My idea it to put a coil up next to the air cooled condenser. The pool water would flow through the coil and pre-cool the air interring the condenser.

The better idea is to use the line that feeds your water heater. The warmer water only helps you on your heating bill. Actually, I know of a person that used the geothermal heat pump and hooked it up this way and got great results.

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Anybody ever heard of someone using a heat exchanger to cool house/heat pool at the same time?

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I know an HVAC contractor in Amarillo that tried to make one. I don't think it worked well.

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There are models with the R&D already done.

For example, http://www.hotspotenergy.com/pool-heater/.

Anscag,

If your goal is to build a house to save energy as ground source heat pump would be low on the list of things to do.

I think you can spend your money on insulation, glass, radiant barriers, insulation, and other items to keep the heat out of your house.

Then I would look at a dual compressor high EER split system to cool your house.

two words: passive solar

Thanks, eric. That's precisely what I had in mind and it doesn't look like I was under or over complicating things too much when I conjured it up in my mind. A simple shell and tube heat exchanger with thermostatic controls to the pool pump.

Natural gas prices are so low at the moment that my payback on the pool heater side would be a stretch, but I'm going to investigate the potential savings on the HVAC side to see if that would make it feasible.

I'm definitely going to investigate it though; our pool is big, deep, and has heavy shade, so it's a prime candidate it would appear.

Thanks again,

Goose.


fyi: I like the water heater idea too, but that's really only going to be a benefit when the water heater is actually filling. I'm thinking it would make better sense for an insta-hot no?

Goose, my buddy has this done for his pool. I think he has 5 loops 100 feet down or so. Keeps it warmer in the winter and cool in the summer.

Oh, I have no intentions of using geothermal. The link eric provided is for a product that transfers heat from your HVAC refrigerant line to the pool water as it returns to the compressor.

Looks like this:


refrigerant lines in/out the top where the copper fittings are, pool water in/out the side at the threaded pvc connections.