The Climate Pilots Nolan and Kathy Stokes are currently working on making their house more climate-smart, including changing their windows and installing a ground source heat pump.
Nolan explains the installation: Ground source heat pumps (GSHP) are electrically powered systems that tap the stored energy of the greatest solar collector in existence: the earth. These systems use the earth's relatively constant temperature to provide heating, cooling, and hot water for homes and commercial buildings. The GSHP is one of the most efficient residential heating and cooling systems available today, with heating efficiencies 50 to 70% higher than other heating systems and cooling efficiencies 20 to 40% higher than available air conditioners. That directly translates into savings for you on your utility bills. Using a desuperheater, some GSHPs can save you up to 50% on your water-heating bill by preheating tank water.
According to the US Energy Information Administration about 41% of energy used in homes is for heating the space; about 8% is for air conditioning but this of course varies by locale; another 20% is for water heating. (http://tonto.eia.doe.gov/energyexplained/index.cfm?page=us_energy_homes ) If we can reduce energy usage by cutting heating by half, cooling by a third and water heating by half, that’s a VERY significant reduction. A quick calculation indicates prospective energy reduction of at LEAST 1/3rd. Of course, I expect better.
Our system at the Falls Church house will be a closed loop system where a mix of water and antifreeze solution is circulated from the heat pump in the house, through plastic pipes buried in a 600 foot well to be drilled into our front yard, down the well and back up again and back into the house. 600 feet is about as tall as the Washington Monument (555 feet 5⅛ inches)!
During the winter, the fluid collects heat from the earth and carries it through the system and into the house. During the summer, the system reverses itself to cool the house by pulling heat from the house, carrying it through the system and placing it in the ground. This process creates free hot water in the summer and delivers substantial hot water savings in the winter.
I got a quote from United Air Temp for $45K and another from a company called Adco for $28K! The system we chose and was installed was $15K and the drilling to install the ground source pipes deep below my yard will be about another $12-15K.
Because of the recent stimulus package changes, good old Uncle Sugar is willing to share in this cost with me to the tune of 30% of the costs. As I understand it I would get a Federal Income Tax Credit. That's a very sweet offer and deserves serious consideration, especially since those folks who normally get phased-out of other tax credits or have them limited by the alternative minimum tax (AMT) are the ones most able to afford the high initial cost of a GSHP.
Ground source heat pumps aka "geothermal" looks MUCH more attractive and MUCH more affordable due to the recent economic stimulus package.
If you are interested in the tax details you can find the 2009 draft version of IRS From 5695 "Residential Energy Credits" and look on Part II, Line 15. There is also a Guide to Federal Tax Incentives for Residential Geothermal Heat Pumps which you can download at: http://www.climatemaster.com/downloads/RP215.pdf .
The IRS calls them "geothermal heat pumps", but the more accurate term is "ground source heat pump". Don't mix up these two terms. A geothermal energy system makes use of the high temperature found just underground in some places. It gathers only heat and doesn't cool. These systems work best, if at all, in locations of volcanic or geologic activity - places like Iceland. In the centers of geologic plates, where there are no volcanoes or "hot spots" near the ground, there can be no geothermal energy collected. Needless to say, this includes Virginia. If somebody says "geothermal" in Virginia, they mean "ground source." They are all very expensive ...
According to the International Ground Source heat Pump Association: “Currently installed systems are making a huge difference in our environment! The systems are eliminating more than three million tons of carbon dioxide and is equivalent of taking 650,000 automobiles off the road. GSHP systems conserve energy and, because they move heat that already exists rather than burning something to create heat, they reduce the amount of toxic emissions in the atmosphere. They use renewable energy from the sun, and because the system doesn't rely on outside air, it keeps the air inside of buildings cleaner and free from pollens, outdoor pollutants, mold spores, and other allergens.”
