My Dearly Beloved™ and I are looking for a weekend house. We know we’ll have a bit of dirt around it. Not more than an acre probably, but something. I’m immensely drawn to Geothermal. Both for air controls and water.
Who’s gone Geothermal? Was it worth it long-term? Was it difficult to get the Geo stuff hooked into the normal house air/ water systems? I figure this desire is going to limit the houses we can look at, because the air aspect means I’m buying forced air for heating/ cooling.
Huge fan of on-demand hot water heaters. Running the incoming water through under ground pipes. Is it done? Does it actually heat up water that’s coming in from the street underground that may be quite cold in the winter? Or is going Geo really about air management and not water temp management?
We put in geothermal when we built our house. We seem to have lower AC bills than our neighbors, but not heat. I guess the heat that comes on when it is too cold for the geothermal is extremely expensive (strip heating or something), so in January or February when I see the red light on the thermostat indicating that the auxiliary heat has switched on, I know money is flying out the window. We built about ten years ago and I’m sure we haven’t made up the extra cost of the geothermal. A friend of ours who is an engineer said we should have put the money in the bank instead and used the interest to pay the higher summer AC bills. I have friends who have geothermal and they’re mostly happy with it, but they also mention the red light on the thermostat. You turn the temp downand put on a sweatshirt or get under a blanket on the couch! I live in central Illinois.
My wife and I are in the early stages of a build. We are particularly interested in the Earthship Model. Check the link and see what innovative designs are out there, lots of other links embedded for all kinds of sustainable systems. We were concerned with finding the right people to build the structure - but then we met with the Chair of the Architecture Department at CU and found out students can get credit for building structures if the proposal for structure is new and unique and within their curricula. So we are exploring this method of build and it is so far showing quite a bit of promise.
Back to Geothermal - I have never seen one built, but we have stayed in a home that used it and asked the homeowner several thousand questions on how efficient it was and which system works more efficiently - water or air?
The main line we got was that geothermal [by itself] was not as efficient for water heating\cooling as the air systems are. This is third hand anecdotal, but if you have other pointed Q’s PM me or ask here as my wife and I have been working on this for a long time and have had mixed results with both companies who do the builds and systems that claim more than they deliver.
I love mine. I have a WaterFurnace system with a horizontal, closed-loop ground loop. How water is not on-demand; that doesn’t seem practical with geo. Instead, I have the gas tank still hooked to the natural gas line, and a pre-heater tank connected to the geo. When the system is operating, the pre-heater tank eventually gets to operating temperature, and fills the gas heater with already-heated water. In theory, the gas burner never fires. Since there’s no pilot light, it doesn’t use gas. We’re only a couple, and I’m pretty confident that the gas never fires during heating or air conditioning season.
For cooling, aside from the higher efficiency, I also get the electricity at half-price because it’s considered “green.” So even if the efficiency were the same as the old system, it would still only cost half as much to operate.
Because I’m on the road so much (as I am now), I use average monthly billing for both my gas and my electricity. My current total electric bill is $88 per month (and I run lots of tech, two refigerators, etc.), whereas four years ago my gas bill alone was $125 per month. The savings really, really are there.
The biggest cost will be those few, super cold mornings that the resistance, auxilliary heater has to kick on. Your system should be sized so that this only occurs few than 15 days per year.
It’s still a forced-air system, but because it runs much longer cycles at temperatures closer to ambient, it doesn’t feel like a typical forced air system that gets hot and cold and has warm and cool spots throughout the house. None of the ducts needed changing. They simply removed the old furnace, installed the new one, new sheet metal, added the electric hot water heater (not connected to mains, just as a pre-heating tank), the ground loop, and removed the old A/C condenser.