Heat Pump Payback in Granite City, IL
Granite City, IL: the heat pump payback math
Here in Granite City, the honest answer is that a heat pump raises your annual running cost. Swap a failed furnace and AC for a heat pump rather than buying like-for-like, and the extra cost here runs $5,500. Unfortunately the electric bill outweighs the gas bill it replaces by about $70 a year here, so the extra spend stays unrecovered. There's no spin on that: Granite City's numbers say wait.
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Granite City is one of 3206 cities covered here, each run through the same model. Search another below.
The climate behind Granite City's payback figure
Degree days tell the story here: Granite City racks up 3639 heating degree days each year (base 65°F), and summers are hot enough that cooling matters as much as heating, with 1688 cooling degree days on the cooling side. The 99% winter design temperature here, the cold snap equipment must be sized for, not the seasonal average, is 1.9°F, and the coldest daily reading in the 2024 station record was -5.1°F. That puts the seasonal coefficient of performance at 2.75 for the recommended cold-climate unit. A cold-climate unit is the right call in Granite City, below 25°F design temperature, a standard heat pump leans hard on electric-resistance backup, which erases most of the savings. Climate figures trace to the nearest NOAA station, St Louis Downtown Airport, 11.1 miles from Granite City.
Granite City's running-cost comparison, in dollars
A 2000-square-foot house here would pull roughly 3,351 heating kilowatt-hours annually on top of cooling, totalling about $913 a year on electricity. That compares with roughly 38 Mcf a year of gas at Granite City's $11.25 per-Mcf rate, about $843 a year with the old AC included, against a local electricity rate of 19.06¢/kWh. With running costs higher every year, there is no payback at any purchase price; over 15 years, against a like-for-like replacement, a household here would end $6,545 behind.
What would change Granite City's answer
The heat pump would become the cheaper option in Granite City if electricity fell to 16.4¢/kWh (from 19.06¢) or gas rose above $13.09 per Mcf (from $11.25). At today's prices a cheaper quote cannot rescue the gas comparison in Granite City, since there is no yearly saving to recover it from.
The other scenario: no gas furnace to begin with
Gas isn't universal in Granite City, many houses run on electric heat already. Swap the comparison to resistance heat instead of gas, and Granite City's answer improves. The saving here runs about $1,260 a year, which recovers the extra $10,000 spent going electric in roughly 7.9 years.
Where Granite City ranks in this dataset
Granite City lands at position 1711 out of 3206 cities on heating severity (coldest is 1), and 1486 out of 3206 by population size (biggest is 1). That's the middle third for winter severity among the cities covered here.
Deciding what's next in Granite City, IL
About 26,854 people live in Granite City, 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.
Ask a local HVAC contractor for a quote before committing either way.
More on how this number was built
Nothing above is a black box: the methodology guide shows the full arithmetic behind Granite City's 2.75 seasonal COP and payback figure. At a 1.9°F design temperature, Granite City sits in cold-climate territory; the guide to that class of unit explains why.