It really depends on your area's natural gas vs electricity prices, which can vary wildly. Electricity can range from 11¢/kWh to 29¢/kWh in California or highe

It really depends on your area's natural gas vs electricity prices, which can vary wildly. Electricity can range from 11¢/kWh to 29¢/kWh in California or higher: https://www.energybot.com/electricity-rates/ https://www.energybot.com/electricity-rates/ Natural gas ranges from (converted) ~ 2¢/kWh to 8¢/kWh in Florida: https://www.eia.gov/energyexplained/natural-gas/prices.php https://www.eia.gov/energyexplained/natural-gas/prices.php (using conversion factors from https://www.nrg.com/resources/energy-tools/energy-conversion-calculator.html https://www.nrg.com/resources/energy-tools/energy-conversion..., which I think assumes 1000 ft^3 ~= 1 therm ~= 29.3 kWh) So your heat pump's COP has to exceed the ratio between natural gas and electricity in your area to make it cost-effective (or you can get solar + battery backup). Electricity prices can vary quite a bit, too... in Cali, for example, it's gone up from 14¢ to 24¢ over 16 years, which is nearly double the rate of inflation.