Based on an EnergySage analysis of a Department of Energy database, a typical heat pump in a typical home uses 5,475 kilowatt hours (kWh) per year—easily the single biggest energy-user in most houses. That’s enough electricity to run nine full-size fridges year round, or power a Tesla Model 3 for 15,000 miles.

In heating mode, a heat pump will use anywhere from 0.86 kWh to 9.00 kWh per hour, from 6.86 kWh to 72 kWh per day, and from 205.71 kWh to 2160 kWh per month. The corresponding running cost (based on $0.15/kWh electricity prices) is $0.13 to $1.35 per hour, $1.03 to $10.80 per day, and $30.86 to $324 per month.

takes in heat energy from a colder area, usually outside It uses electricity to do this. But it produces much more heat energy than it uses in electrical energy. This makes heat pumps a more energy efficient way to heat your home than a traditional gas or oil boiler. It also produces far fewer carbon emissions than other heating systems.

Heat pumps draw up to 75% of their energy needs from nature for free, with the remainder powered by electricity to drive the compressor and heat exchanger. But that doesn’t necessarily mean a high electricity bill. How much electricity a heat pump uses depends on several factors.

A heat pump that has a CoP of three can create three kW of heat from every one kW of electricity. The average home requires around 12,000 kilowatt hours (kWh) of heat per year. Therefore, in order to achieve this, a heat pump with a CoP of three would use 4,000 kWh of electricity annually.