If a solar retrofit isn’t in the cards, you may want to consider a heat pump. A heat pump is an ingenious device designed to extract heat from the ground or the air around a home in the winter, concentrate it, and then transfer the heat into the interior of the structure. Heat pumps can be used as the primary heat source for new or existing homes. They’re ideal for sites that aren’t conducive to solar energy retrofits.

What makes heat pumps so special is that they don’t burn fossil fuel like many conventional home heating systems. They operate entirely on electricity. (Electricity may be generated from fossil fuels, however, and usually is.) Moreover, heat pumps can be run in reverse during the summer to extract heat from our homes.

Heat pumps fit into two basic categories: air-source and ground-source. Let’s begin with the ground-source heat pump.