A properly installed and sized high-efficiency air source heat pump in our climate will heat about 75% of the time in the winter months. When the outside air temperature drops below about 25 degrees F, the supplemental heat will engage to assist in maintaining the temperature in the home for about 25% of the time. During extremely cold temperatures, the supplemental heat will be the primary source of heat. The annual energy savings from an air source heat pump are mostly achieved because it only uses about 25% of the power to heat your home when compared to an electric furnace. Overall savings are about 30 to 50% over a conventional electric forced air furnace.
A ground source heat pump is the most efficient way to heat your home. Typically a ground loop is buried in the ground, or groundwater is used to heat your home and preheat your hot water. Because the ground or water temperatures stay at a constant temperature, the ground source heat pump can take heat from the ground to maintain the temperature in your home with little or no supplemental heat! Overall savings can reach over 70%