Lomita, CA: the heat pump payback math

This one's marginal in Lomita: it only clears if you stay long enough. $1,000 is what Lomita would pay extra to go electric rather than replace the furnace and AC with the same again, once the $2,000 federal credit is applied. That premium is recovered through $95 of lower running costs every year, landing the payback clock at roughly 10.5 years. It's a genuine toss-up here — Lomita's numbers don't point clearly either way.

How cold Lomita actually gets

Degree days tell the story here: Lomita racks up 1112 heating degree days each year (base 65°F), and summers add a moderate cooling load, with 821 cooling degree days on the cooling side. Sizing runs off the design temperature, not the average day: 37.4°F here (record low 35.6°F), which works out to a seasonal COP of 3.31 for the standard class of unit this climate calls for. Lomita's winters don't get cold enough to need the cold-climate premium — a standard unit holds up fine. These numbers come from ZAMPERINI FIELD AIRPORT, the closest NOAA station, 1.5 miles out.

What it actually costs to run, year to year

A 2000-square-foot house here would pull roughly 851 heating kilowatt-hours annually on top of cooling, totalling about $509 a year on electricity. Lomita's gas rate of 22.01 per Mcf, applied to the 12 Mcf a year the furnace burns, puts its running cost near $604 a year, against 32.83¢ per kWh for electricity. Priced as a standalone purchase rather than against a like-for-like replacement, equipment payback runs about 115.6 years, for a 15-year net position $427 ahead.

If your home heats with electric baseboard instead of gas

Not every home in Lomita has gas service. Against electric-resistance heat — baseboard or an electric furnace, both 100% efficient but still just resistance — the case for switching gets stronger here. The saving here runs about $765 a year, which recovers the extra $5,500 spent going electric in roughly 7.2 years.

Where Lomita ranks in this dataset

Among 3206 cities, Lomita's winter puts it at rank 2850 for severity, while its size puts it at rank 1939 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.

What to do with this number in Lomita

Lomita, California is home to about 19,841 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 Lomita, nothing is lost by holding off until the current equipment genuinely fails.

Get quotes from local HVAC contractors before deciding.

Where Lomita's figure comes from

Every constant behind this page — the 3.31 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Homes in Lomita without gas service should read the electric-resistance comparison instead — the numbers there differ from the gas case above.