Written by Brad Crawford
Geothermal heat pumps, refrigerators, and air conditioners have one thing in common: they remove heat from one place and transfer it to a different place. Geothermal heat pumps let you control the temperature in your home year-round, because the cycle is reversible — you can take heat out of your house in the summer, and put it into the ground or a standing water supply, like a pond. Or you can take the heat out of the ground in the winter, and have it transferred into your home.
When installed correctly, geothermal heat pumps can deliver two to four times more heat to a home than the actual energy they use to operate, which makes them very efficient. Overall benefits include:
- Decreased utility bills (25 to 70 percent less than conventional HVAC systems)
- Less maintenance
- Controlled climate, more comfort year-round
- Lower emissions
Two main types of heat pumps are on the market today: air source and geothermal. Air source pumps take heat from an air source, whether inside your home or outside. A geothermal pump will draw its heat energy from a different source, whether the earth, ground water, or another water source.
Efficiency should be a top priority when you’re looking into purchasing a heat pump. Energy Star-labeled systems operate 8 to 20 percent more efficiently than traditional HVAC systems. However, the size of the system is a key factor in the final price.
Your system needs to be sized by an HVAC profession, but the general rule of thumb is you will need one “ton” of geothermal heat pump for every 400 square feet of home you want to serve. For example, if your home is 2,000 square feet, you will need a 5-ton heat pump. (This isn’t a ton in the traditional sense, but rather a term that originally referred to how much ice was needed to cool a certain amount of air.)