Inkster, MI: the heat pump payback math

Here in Inkster, the honest answer is that a heat pump raises your annual running cost. Against a like-for-like gas furnace and AC swap, going electric costs $3,500 more up front here (already netting out a $2,000 tax credit). The heat pump would cost about $300 more a year to run than the furnace it replaces — a premium with no payback. That's Inkster's own climate and rates talking, not a hedge or a caveat.

How cold Inkster actually gets

Inkster has a cold winter that leans hard on heating equipment — 5000 heating degree days a year against a 65°F base — and summers add a moderate cooling load, at 928 cooling degree days. Sizing runs off the design temperature, not the average day: 1.9°F here (record low -2.9°F), which works out to a seasonal COP of 2.75 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, Inkster sits firmly in cold-climate territory, so that's the class of unit priced here. These numbers come from DETROIT METRO WAYNE COUNTY AI, the closest NOAA station, 4.4 miles out.

What it actually costs to run, year to year

Electricity use for heating alone comes out to about 4,604 kWh a year on the 2000-square-foot reference house; folding in cooling puts the electric bill near $1,118 a year. That compares with roughly 52 Mcf a year of gas at Inkster's 10.92 per-Mcf rate — about $818 a year — against a local electricity rate of 20.72¢/kWh. Priced as a standalone purchase rather than against a like-for-like replacement, equipment payback runs past the 15-year equipment life, for a 15-year net position $8,000 behind.

Electric resistance heat in Inkster, compared

Gas isn't universal in Inkster — many houses run on electric heat already. Compared with baseboard or electric-furnace resistance heat, the numbers shift in the heat pump’s favor. Switching saves about $1,755 a year here — a heat pump moving heat rather than generating it needs far less electricity than resistance coils — so the extra $8,000 spent up front comes back in about 4.6 years.

Inkster against the rest of the country

Inkster lands at position 700 out of 3206 cities on heating severity (coldest is 1), and 1598 out of 3206 by population size (biggest is 1). That's the coldest third of the dataset, where climate does most of the work behind this figure.

What to do with this number in Inkster

Inkster, Michigan is home to about 25,108 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 Inkster, nothing is lost by holding off until the current equipment genuinely fails.

Line up a few local HVAC quotes before you decide.

Where Inkster's figure comes from

Every constant behind this page — the 2.75 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Inkster's 1.9°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.