Heat pump systems offer an energy-efficient alternative to furnaces and air conditioners for climates with moderate heating and cooling needs. Heat pumps use electricity to move heat from cool to warm space like refrigerators. During the heating season, heat pumps move heat from the cool outdoors into your warm house and during the cooling season, pumps move heat from your cool house into the warm outdoors. Because they move heat rather than generate heat, heat pump systems can provide equivalent space conditioning at as 1/4 of the cost of operating conventional heating or cooling appliances.