Redwood City, CA: the heat pump payback math
The payback math works in Redwood City on paper, past the equipment's own working life. Against a like-for-like gas furnace and AC swap, going electric costs $1,000 more up front here (already netting out a $2,000 tax credit). Redwood City's residents would see roughly $2 a year back in running costs, putting the payback around 522 years. That's a technicality, not a recommendation, for anyone actually living in Redwood City.
Redwood City's weather, in the numbers that matter
Degree days tell the story here: Redwood City racks up 2270 heating degree days each year (base 65°F), and summers rarely ask much of an air conditioner, with 218 cooling degree days on the cooling side. 41.2°F is the figure equipment gets sized against here — the 99th-percentile cold snap, not an average day — with a record low of 38.8°F on file. Worked through the model, that's a seasonal COP of 3.43 on the standard unit fit for this climate. Redwood City's winters don't get cold enough to need the cold-climate premium — a standard unit holds up fine. These numbers come from REDWOOD CITY, the closest NOAA station, 0.9 miles out.
Redwood City's running-cost comparison, in dollars
A 2000-square-foot house here would pull roughly 1,676 heating kilowatt-hours annually on top of cooling, totalling about $611 a year on electricity. Redwood City's gas rate of 22.01 per Mcf, applied to the 24 Mcf a year the furnace burns, puts its running cost near $613 a year, against 32.83¢ per kWh for electricity. Looked at as a full purchase rather than an incremental one, payback here is roughly 5742.2 years, leaving the 15-year total $971 behind.
Electric resistance heat in Redwood City, compared
Not every home in Redwood City has gas service. Compared with baseboard or electric-furnace resistance heat, the numbers shift in the heat pump’s favor. About $1,369 a year comes back this way, enough that the 4-year payback clears the $5,500 premium comfortably within the equipment's life.
How Redwood City compares nationally
Ranked against the other 3206 cities covered, Redwood City comes in at 2292 for heating severity — 1 would be the coldest place in the dataset — and 444 by population, where 1 is largest. That's the mildest third of cities covered, where utility rates carry more of the answer than climate does.
What to do with this number in Redwood City
Redwood City, California is home to about 82,982 people, and the figures above are the same ones a local HVAC contractor uses to size and quote a system — this site doesn't guess where a real quote would land, it just tells you whether it's worth asking for one. In Redwood City, nothing is lost by holding off until the current equipment genuinely fails.
Line up a few local HVAC quotes before you decide.
Where Redwood City's figure comes from
Nothing above is a black box: the methodology guide shows the full arithmetic behind Redwood City's 3.43 seasonal COP and payback figure. Redwood City technically clears a payback on paper, just past the equipment's own working life — the no-payback guide explains why that distinction matters.