A ground source heat pump (GSHP) and a geothermal heating and cooling system are actually the same thing. Geothermal systems are also referred to as ground source heat pumps because they use ground source energy (stored solar energy) to heat and cool homes.

The three main parts consist of a geothermal unit, an underground piping system (open or closed loop) and ductwork.

While outdoor temperatures fluctuate with changing seasons, underground temperatures don't. Four to six feet below the earth's surface, temperatures remain relatively constant, and a geothermal system capitalizes on these temperatures to provide energy. In winter, a series of fluid-filled underground pipes called a "loop" absorbs stored heat, which is transferred indoors. An indoor pump compresses the heat to a higher temperature and distributes it throughout your home. In summer, the system reverses, pulling heat from your home, carrying it through the earth loop and depositing it into the cooler earth.

Unlike ordinary systems, geothermal systems do not use fossil fuels to generate heat. They simply transfer heat to and from the earth to provide a more efficient, affordable and environmentally friendly method of heating and cooling. Typically, only a small amount of electricity is used to operate the unit's fan, compressor and pump.

Costs will vary by location, the size of your home, equipment installed, and local incentives, but on average you can expect to pay between $18,000 to $30,000 for the installation, the indoor unit, and the underground loops. As a reminder, the system will end up paying for itself in three to four years.

Anywhere. Literally. Geothermal systems can be installed in the city, suburbs or rural areas; anywhere between the mountains and the Caribbean; in old or new homes and buildings; and in small or large structures. We've even seen geothermal used frequently to regulate greenhouses. There's no structure geothermal can't heat and cool.

Absolutely. Geothermal can be installed in several ways, depending upon your needs. A hybrid system can supplement your existing traditional system if your furnace is still in good condition and you live in a particularly cold area. In this case, the geothermal system provides 90% of your home‘s heating requirements, and the traditional system turns on when the outdoor temperature reaches a certain low temperature. Geothermal systems can work on their own in very cold temperatures, but when paired with a traditional system, this combination can create a favorable solution for efficient heating.Geothermal can also be installed to completely replace your traditional system, which is usually the most efficient solution. In either scenario, the ground loop will need to be installed to make geothermal work for you.

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Compared to the most efficient traditional system, a geothermal system is over five times more efficient in heating and more than twice as efficient in cooling. Because geothermal systems move existing heat rather than creating it through combustion, they provide four to five units of energy for every one unit used to power the system.

All heating and cooling systems have a rated efficiency from a U.S. governmental agency. Fossil fuel furnaces use Annual Fuel Utilization Efficiency (AFUE). Air conditioners use Seasonal Energy Efficiency Ratio (SEER), while heat pumps use High Seasonal Performance Factor (HSPF) and SEER. It’s a scientific way of determining how much energy the system produces versus how much it uses. Most geothermal heat pump systems have COPs of 3-4.5. Where a fossil fuel furnace may be 78-98% efficient, a geothermal heat pump is over 500% efficient.

No. Geothermal systems are practically maintenance free. The buried loop will last for generations. The unit’s fan, compressor and pump is housed indoors, protected from the weather and contamination. Usually, periodic checks and filter changes are the only required maintenance.

Geothermal does play nice with solar power, and in combination, the two systems will help you be even less dependent on fossil fuels. Installing a geothermal system first allows you to use less solar energy.