Is a Heat Pump or Gas Furnace More Efficient to Operate?

Why there is no quick answer

People often ask whether a gas furnace or a heat pump is cheaper to run, hoping for one clear winner. The honest answer is that it depends on several variables working together. The main factors are how many hours the system runs each season, the cost per kilowatt hour of electricity, the cost per therm of natural gas, the efficiency of the furnace, and the HSPF (heating seasonal performance factor) of the heat pump. Change any one of these and the result can change too.

The numbers that decide it

Furnace efficiency is measured as AFUE, the percentage of fuel turned into usable heat. An 80% furnace turns most of its gas into heat, and a 90% or higher condensing furnace wastes even less. Heat pump efficiency is rated by HSPF, which reflects how much heat it moves per unit of electricity across a season. A higher HSPF means lower electric heating cost.

A useful general rule

As a broad generalization, in most areas of the country an 80% furnace will consume about the same amount of energy as a heat pump, assuming the operating time and climate are comparable. The picture shifts with your location. In a colder climate, natural gas is normally the best choice when it is available, because a furnace keeps full output in deep cold while a heat pump loses efficiency as the temperature drops.

Get a local opinion

The only way to really answer this for your home is to apply these factors to your own conditions. Check with a local contractor and do not be afraid to ask questions. Keep in mind that some contractors favor one system or the other for reasons that have nothing to do with operating cost or comfort, so ask them to show the math behind their recommendation.