Follow geothermal energy tips for home heating, cooling
Increasing energy costs have many homeowners looking for new ways to save money. According to the Department of Energy, the average homeowner pays about $1,900 a year on utilities, most of it going toward heating and cooling bills.
A growing number of homeowners are finding savings in their own back yards by utilizing the earth's natural energy to heat and cool their homes. This is geothermal energy, and it can save on utility bills.
Bosch Thermotechnology North America has released a guide to geothermal energy:
Geothermal systems — also known as ground source heat pump systems (GSHPS) or geothermal heat pumps (GHPs) — have been around for decades but are a green option that many homeowners are just beginning to learn about.
The Department of Energy and the Environmental Protection Agency have both endorsed ground source heat pump systems as among the most energy-efficient and environmentally friendly heating, cooling and water heating systems available.
How Geothermal Systems Work
The temperature of the earth below the surface — from a few feet to hundreds of feet down — is moderate and fairly constant. In many places it stays in the mid- to upper-50s all year. Instead of burning fossil fuels, a geothermal heat pump absorbs the energy stored in the earth to heat a home in the winter. In the summertime a heat pump rejects the heat from the space and transfers it back into the earth, making it extremely efficient and cost-effective.
To make it work, you need three basic elements: an underground loop system, a geothermal heat pump and an air-delivery system.
- Loop System: This is a system of high-density polyethylene plastic pipes buried in the ground. They are filled with fluid, a mixture of water and antifreeze, which circulates throughout the pipes. Open-loop systems circulate water drawn from a well.
- Geothermal Heat Pump: The geothermal heat pump extracts heat from the fluid within the loop using a vapor-compression refrigeration cycle. This heat is then sent into the home. In the summer, it extracts heat from the indoor air and transfers it to the fluid, which cools as it circulates through the loop.
- Air-delivery System: Most geothermal pumps use an electrically driven fan to distribute the air through ducts in the home.
A residential system can also be equipped to heat household water.
According to the International Ground Source Heat Pump Association, a geothermal system has efficiencies 50 to 70 percent higher than other heating systems and cooling efficiencies 20 to 40 percent higher than available air conditioners. That means direct savings on home utility bills.
How Geothermal Systems Save You Money
According to Bosch Thermotechnology North America:
- You can save up to 70 percent on your energy bill, depending on location and which GSHPS you use.
- Although the upfront costs are often more than a conventional system, the cost can be recouped within a short period of time — as little as 5 to 7 years.
- Local and federal tax credits as well as rebates decrease installation costs.
- Costs may be further reduced by special financing options offered by heat pump manufacturers, local utilities and lending institutions.
- Geothermal heat pumps have the lowest life cycle cost today — 25 to 50 percent less than a conventional system.
Geothermal Systems: Available Tax Credits
Under the recent tax credit legislation, a taxpayer who installs a geothermal heat pump in a residence could be eligible for a tax credit of 30 percent of the installed cost of the system.
The system must meet Energy Star requirements in effect at the time the system is completed. This credit is not limited to the primary residence, but may be used for any property a taxpayer owns. Equipment must be "placed in service" between January 1, 2009 and December 31, 2016.
Geothermal: The Earth-Friendly Choice
- About a million geothermal systems have been installed in the U.S. since 1980. They save more than 14 million barrels of crude oil per year.
- Current geothermal systems are eliminating more than 3 million tons of carbon dioxide — the equivalent of taking 650,000 automobiles off the road.
- Geothermal systems have no carbon dioxide emissions or any other negative effects on the environment.
For more information, see our Energy Efficient Heating & Cooling (HVAC) Research Center.
Topics: Heating & Cooling