Heat Pump Payback in Monroe, WA
Monroe, WA: the heat pump payback math
Monroe technically pencils out, but only past the point the equipment would need replacing anyway. Against a like-for-like gas furnace and AC swap, going electric costs $5,500 more up front here. Monroe's residents would see roughly $318 a year back in running costs, putting the payback around 17.3 years. That's a technicality, not a recommendation, for anyone actually living in Monroe.
Compare against another city
This runs the same numbers for 3206 US cities, not just Monroe. Look one up here.
How cold Monroe actually gets
Monroe has a real but manageable winter, 4489 heating degree days a year against a 65°F base, and summers rarely ask much of an air conditioner, at 200 cooling degree days. Sizing runs off the design temperature, not the average day: 18°F here (coldest 2024 reading 12.9°F), which works out to a seasonal COP of 3.13 for the cold-climate class of unit this climate calls for. Below the 25°F line where a standard machine starts leaning on resistance backup, Monroe sits firmly in cold-climate territory, so that's the class of unit priced here. Source: NOAA station Snohomish Co (Paine Fd) AP, 14.1 miles from Monroe, the closest one on record.
What it actually costs to run, year to year
A 2000-square-foot house here would pull roughly 3,632 heating kilowatt-hours annually on top of cooling, totalling about $543 a year on electricity. That compares with roughly 47 Mcf a year of gas at Monroe's $17.62 per-Mcf rate, about $861 a year with the old AC included, against a local electricity rate of 14.27¢/kWh. 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 $727 behind.
The break-even point in Monroe
Gas would only overtake the heat pump in Monroe if electricity rose past 23.3¢/kWh from 14.27¢, or gas fell under $10.81 per Mcf from $17.62. A useful quote test for Monroe: the heat pump is worth it within a decade if it costs less than $3,180 more than replacing the furnace and AC, and within 7 years if the gap is under $2,226.
If your home heats with electric baseboard instead of gas
Gas isn't universal in Monroe, many houses run on electric heat already. Swap the comparison to resistance heat instead of gas, and Monroe's answer improves. The saving here runs about $1,116 a year, which recovers the extra $10,000 spent going electric in roughly 9 years.
How Monroe compares nationally
Among 3206 cities, Monroe's winter puts it at rank 1210 for severity, while its size puts it at rank 1931 for population, 1 in both cases being the extreme. That's the middle third for winter severity among the cities covered here.
What to do with this number in Monroe
Monroe, Washington is home to about 19,927 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 Monroe, nothing is lost by holding off until the current equipment genuinely fails.
Ask a local HVAC contractor for a quote before committing either way.
More on how this number was built
Every constant behind this page, the 3.13 seasonal COP, the degree-day corrections, the equipment costs, is documented in the methodology guide. Monroe's 18°F design temperature is below the 25°F line, which is why a cold-climate unit is the right call here, see what that changes in the cold-climate unit guide.