Will a heat pump pay off in Frankfort, IL?
Frankfort is a place where a heat pump genuinely costs more to operate than the alternative. 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 $250 more a year to run than the furnace it replaces — a premium with no payback. That's Frankfort's own climate and rates talking, not a hedge or a caveat.
How cold Frankfort actually gets
4951 heating degree days pile up here every year, so Frankfort has a real but manageable winter; the cooling side runs to 1049 cooling degree days, where summers are hot enough that cooling matters as much as heating. The 99% winter design temperature here — the cold snap equipment must be sized for, not the seasonal average — is -4°F, against a record low of -13°F. That puts the seasonal coefficient of performance at 2.6 for the recommended cold-climate unit. A cold-climate unit is the right call in Frankfort — 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, LEWIS UNIVERSITY AIRPORT, 12.9 miles from Frankfort.
Frankfort's running-cost comparison, in dollars
A 2000-square-foot house here would pull roughly 4,822 heating kilowatt-hours annually on top of cooling, totalling about $1,090 a year on electricity. Frankfort's gas rate of 11.25 per Mcf, applied to the 52 Mcf a year the furnace burns, puts its running cost near $839 a year, against 19.06¢ per kWh for electricity. Looked at as a full purchase rather than an incremental one, payback here is longer than the 15-year equipment life, leaving the 15-year total $7,254 behind.
The other scenario: no gas furnace to begin with
Plenty of homes in Frankfort heat with electricity alone, no gas line involved. Against electric-resistance heat — baseboard or an electric furnace, both 100% efficient but still just resistance — the case for switching gets stronger here. About $1,559 a year comes back this way, enough that the 5.1-year payback clears the $8,000 premium comfortably within the equipment's life.
Where Frankfort ranks in this dataset
Ranked against the other 3206 cities covered, Frankfort comes in at 812 for heating severity — 1 would be the coldest place in the dataset — and 1833 by population, where 1 is largest. That's the coldest third of the dataset, where climate does most of the work behind this figure.
Next step for 21,160 people in Frankfort
Frankfort, Illinois is home to about 21,160 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 Frankfort, nothing is lost by holding off until the current equipment genuinely fails.
Line up a few local HVAC quotes before you decide.
Where Frankfort's figure comes from
Every constant behind this page — the 2.6 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Frankfort's -4°F design temperature falls on the cold side of the 25°F cutoff the cold-climate unit guide walks through.