Should Gilbert switch to a heat pump?
In Gilbert, a heat pump is the cheaper choice, and not by a little. $1,000 is what Gilbert 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. Lower bills claw that back: about $401 saved annually, for a payback of roughly 2.5 years. That verdict holds specifically for Gilbert's own climate and rates, not a national average.
How cold Gilbert actually gets
1399 heating degree days pile up here every year, so Gilbert barely has a winter to speak of; the cooling side runs to 4472 cooling degree days, where summers are severe enough that cooling can dominate the annual bill. 30.2°F is the figure equipment gets sized against here — the 99th-percentile cold snap, not an average day — with a record low of 28.4°F on file. Worked through the model, that's a seasonal COP of 3.1 on the standard unit fit for this climate. Gilbert's winters don't get cold enough to need the cold-climate premium — a standard unit holds up fine. Source: NOAA station WILLIAMS GATEWAY AIRPORT, 4.5 miles from Gilbert — the closest one on record.
What it actually costs to run, year to year
A 2000-square-foot house here would pull roughly 1,143 heating kilowatt-hours annually on top of cooling, totalling about $771 a year on electricity. The gas furnace it replaces burns roughly 15 Mcf a year at 18.58 per Mcf here, for a running cost near $1,172 a year (electricity here runs 15.55¢/kWh). Looked at as a full purchase rather than an incremental one, payback here is roughly 27.4 years, leaving the 15-year total $5,020 ahead.
The other scenario: no gas furnace to begin with
Not every home in Gilbert has gas service. Swap the comparison to resistance heat instead of gas, and Gilbert's answer improves. The saving here runs about $681 a year, which recovers the extra $5,500 spent going electric in roughly 8.1 years.
Gilbert against the rest of the country
Among 3206 cities, Gilbert's winter puts it at rank 2722 for severity, while its size puts it at rank 76 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.
Deciding what's next in Gilbert, AZ
Gilbert, Arizona is home to about 288,790 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. Given the math above, Gilbert is a place worth lining up quotes ahead of a breakdown, not waiting for one.
Get quotes from local HVAC contractors before deciding.
More on how this number was built
The methodology guide walks through exactly how Gilbert's 3.1 seasonal COP and the rest of this page's numbers get built. The $2,000 federal credit baked into Gilbert's number is explained, with the before-and-after math, in the tax credit guide.