The heat from the Earth is known as geothermal energy. Geothermal systems heat or cool a home (or other building) by using the stable temperature of the Earth. Depending on the season, this energy can be used either as heat or a coolant. An alternative to using heating fuel or electric heat, and electric air conditioners, geothermal systems use an electric pump to draw out heat from deep inside the Earth. During hot months of the year, the process reverses and the pump removes hot air from your home, dumping it deep in the Earth and then replacing it with cooler air, conditioned by the ground.
Basic Geothermal Systems
Two basic geothermal systems can be installed in residential homes. The closed-loop geothermal heat pump has a horizontal or vertical pipe that acts as a heat exchanger for water to move heat from the ground into the system and back again; the open-loop system uses water pumped from a well (or other groundwater source) through the heat exchanger system and back to originating water source. The closed-loop system is the more popular of the two since it is more versatile. In addition, the open-loop system is not permitted to be used in all regions, especially shoreland zoning areas or other regions where eco-systems are fragile.
Benefits of Residential Geothermal Systems
Installing a geothermal heat pump is not just about preserving the environment.
- While oil prices rise, electricity prices remain relatively stable, making heating costs with geothermal more predictable than oil.
- Since geothermal systems don't generate heat, but just move it, they use a lot less energy than electric heat and oil heat systems.
- Geothermal produces less pollution than burning wood for heat.
- If you have solar panels or other electricity-generating equipment, the cost of geothermal heat is free (once you connect the heat pump to your electric source).
- You can install a geothermal system in both new and existing construction. Installing geothermal in a new structure is much easier than retrofitting, although both are possible.
- Geothermal systems produce less noise and require less maintenance than traditional heating and cooling systems.
- Many utility companies offer a reduced rate for residential customers and businesses that use a geothermal system.
FAQs About Geothermal
- What is a geothermal heat pump?
A geothermal heat pump (GHP) is the tool used within the system to actually transfer heat from one source to another. This usually means from the ground, into your system and thereby your home.
- What is the difference between geothermal systems and traditional sources of heating and cooling?
Traditional systems rely on burning fuel, usually at a power plant. This creates harmful emissions into the environment. Geothermal residential heating and cooling systems draw directly from the Earth's natural sources of heating and cooling, making it the more environmentally friendly option.
- Is this method of heating and cooling sanctioned by the United States government?
Most geothermal heat pumps do have the Energy Star branding, given by the Environmental Protection Agency and the Department of Energy.
- Where in the United States does geothermal heating work best?
While it works everywhere, the cost savings are most significant in regions where summer and winter temperature differences are the largest, such as the New England states.
- What kinds of houses are best for geothermal heat?
Homeowners with large houses have the biggest cost savings of geothermal heat. In order to find out about your own house plans or the house you already own, consult a geothermal specialist for not only advice, but also for an estimate on installing a system.
- What is the price difference between a traditional heating and cooling system and the geothermal variety?
The cost of a geothermal system depends on whether it is a new building or you are adding geothermal to an older building; the size of the building, the quality of the insulation and the fittings of doors and windows and the type of system you install (closed or open and whether the loops are horizontal or vertical). According to Energy Homes, an average system for an average-sized home is $25,000, about twice as much as a more conventional system. While this is a lot of money upfront, geothermal systems often last twice as long as conventional systems, and there is a 30 percent rebate from the United States Government through 2016. Another consideration is that your monthly costs will be lower.
- How much can I expect to save on my energy bill?
Geothermal systems use about 25 to 50 percent less energy than a conventional HVAC (Heating Ventilating and Air Conditioning) system. Up to 70 percent energy reduction is possible, according to GeoComfort. This translates into a monthly savings of at least $30 and as much as $90 each month. The geothermal system essentially pays for itself in a matter of a few years. After that point, the savings translate into more money in the homeowner's pocket. This reduction in monthly heating bills has made geothermal an attractive selling point in the real estate market. Adding geothermal to your home essentially increases its value compared to other homes in your area that have traditional HVAC systems.
Whether you install geothermal because it is clean and quiet, because it costs less over a period of 25 years than traditional HVAC units, or because you have a commitment to doing your part to save the planet, it is a good way to go. While the cost of installing a system is significant, the long-term benefits are worth it for many homeowners.