Is a heat pump worth it in Decatur?
Here in Decatur, 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 $172 more a year to run than the furnace it replaces — a premium with no payback. There's no spin on that: Decatur's numbers say wait.
Why Decatur's climate drives this number
Decatur has a real but manageable winter — 4340 heating degree days a year against a 65°F base — and summers are hot enough that cooling matters as much as heating, at 1300 cooling degree days. -2°F is the figure equipment gets sized against here — the 99th-percentile cold snap, not an average day — with a record low of -9.9°F on file. Worked through the model, that's a seasonal COP of 2.65 on the cold-climate unit fit for this climate. Decatur needs the cold-climate class of unit: past a 25°F design temperature a standard heat pump falls back on resistance backup often enough to eat the savings. Source: NOAA station DECATUR AIRPORT, 3.9 miles from Decatur — the closest one on record.
The month-to-month numbers for Decatur
A 2000-square-foot house here would pull roughly 4,147 heating kilowatt-hours annually on top of cooling, totalling about $1,002 a year on electricity. The gas furnace it replaces burns roughly 45 Mcf a year at 11.25 per Mcf here, for a running cost near $830 a year (electricity here runs 19.06¢/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 $6,081 behind.
The other scenario: no gas furnace to begin with
Gas isn't universal in Decatur — many houses run on electric heat already. Swap the comparison to resistance heat instead of gas, and Decatur's answer improves. About $1,414 a year comes back this way, enough that the 5.7-year payback clears the $8,000 premium comfortably within the equipment's life.
How Decatur compares nationally
Among 3206 cities, Decatur's winter puts it at rank 1286 for severity, while its size puts it at rank 568 for population — 1 in both cases being the extreme. That's the middle third for winter severity among the cities covered here.
Deciding what's next in Decatur, IL
About 68,763 people live in Decatur, Illinois, and every number on this page is what a contractor would actually work from when quoting a system here — the point isn't to replace that quote, it's to tell you whether to bother asking for one. Here, there's no cost penalty to waiting until your current furnace or AC actually needs replacing.
Get quotes from local HVAC contractors before deciding.
Reading further on this page's numbers
Every constant behind this page — the 2.65 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Decatur's -2°F design temperature falls on the cold side of the 25°F cutoff the cold-climate unit guide walks through.