At 45°F ambient, how much more efficient can a heat pump system be compared to electric resistance heat?

A heat pump system operates by extracting heat from the outside air and transferring it indoors, even at lower temperatures like 45°F. This process relies on the principles of thermodynamics and the efficiency of the refrigeration cycle. When comparing the efficiency of a heat pump to electric resistance heating, the coefficient of performance (COP) is a critical factor to consider.

At ambient temperatures around 45°F, a heat pump can achieve a COP of 3 to 4. This means that for every unit of electricity consumed, the heat pump can deliver three to four units of heat energy into the space being heated. In contrast, electric resistance heating converts electrical energy directly into heat at an efficiency rate of 1:1, which means it produces only one unit of heat for each unit of electricity used.

Therefore, the efficiency difference between the two systems becomes quite significant. When considering that a heat pump can produce anywhere from three to four times the energy output for the same input compared to electric resistance, it highlights the considerable advantage heat pumps have, especially in moderate climates.

This understanding underscores why the choice indicating that a heat pump system can be three to four times more efficient than electric resistance heat is accurate.