Heat Pump Payback in Belmont, CA
Should Belmont switch to a heat pump?
Belmont technically pencils out, but only past the point the equipment would need replacing anyway. $3,000 is what Belmont would pay extra to go electric rather than replace the furnace and AC with the same again. Belmont's residents would see roughly $8 a year back in running costs, putting the payback around 386 years. Belmont's own numbers say this pencils out only in theory, not in practice.
Not the city you meant?
This runs the same numbers for 3206 US cities, not just Belmont. Look one up here.
Why Belmont's climate drives this number
Belmont has a mild winter by US standards, 2349 heating degree days a year against a 65°F base, and summers add a moderate cooling load, at 335 cooling degree days. The 99% winter design temperature here, the cold snap equipment must be sized for, not the seasonal average, is 39.2°F, and the coldest daily reading in the 2024 station record was 37.4°F. That puts the seasonal coefficient of performance at 3.37 for the recommended standard unit. A standard ducted system is enough here; Belmont's design temperature doesn't justify the cold-climate premium. Source: NOAA station San Carlos Airport, 2.4 miles from Belmont, the closest one on record.
Belmont's running-cost comparison, in dollars
Modelled on a typical 2000-square-foot house, the heat pump draws about 1,765 kWh a year to keep it warm, plus cooling, for a combined electric bill near $673 a year. Belmont's gas rate of $22.01 per Mcf, applied to the 24 Mcf a year the furnace burns, puts the current furnace-and-AC running cost near $681 a year, against 32.83¢ per kWh for electricity. Buying outright rather than at replacement time stretches payback to longer than the 15-year equipment life. Over 15 years, compared with a like-for-like replacement, the heat pump leaves you $2,883 behind.
How sensitive Belmont's result is to prices
This result holds unless electricity climbs above 33.3¢/kWh (it is 32.83¢ now) or gas drops below $21.69 per Mcf (now $22.01); past either point, gas becomes the cheaper fuel in Belmont. When quotes arrive, compare the heat pump price with a like-for-like furnace and AC replacement: at $8 a year saved, a difference under $56 pays back within 7 years here, and under $80 within 10.
The other scenario: no gas furnace to begin with
Gas isn't universal in Belmont, many houses run on electric heat already. Against electric-resistance heat, baseboard or an electric furnace, both 100% efficient but still just resistance, the case for switching gets stronger here. About $1,422 a year comes back this way, enough that the 5.3-year payback clears the $7,500 premium comfortably within the equipment's life.
Belmont against the rest of the country
Among 3206 cities, Belmont's winter puts it at rank 2254 for severity, while its size puts it at rank 1467 for population, 1 in both cases being the extreme. That's the mildest third of cities covered, where utility rates carry more of the answer than climate does.
Next step if you live in Belmont
About 27,132 people live in Belmont, California, and every number on this page is what a contractor would actually work from when quoting a system here, the point isn't to replace that quote, it's to tell you whether to bother asking for one. Here, there's no cost penalty to waiting until your current furnace or AC actually needs replacing.
Get quotes from local HVAC contractors before deciding.
More on how this number was built
Nothing above is a black box: the methodology guide shows the full arithmetic behind Belmont's 3.37 seasonal COP and payback figure. Belmont's case is the "pays back too slowly to count" kind covered in the guide to cities where the math never really works.