Tullahoma, TN: the heat pump payback math
Tullahoma technically pencils out, but only past the point the equipment would need replacing anyway. Swap a failed furnace and AC for a heat pump rather than buying like-for-like, and the extra cost here runs $3,500 after a $2,000 federal tax credit. That premium is recovered through $83 of lower running costs every year, landing the payback clock at roughly 42.1 years. Tullahoma's own numbers say this pencils out only in theory, not in practice.
The climate behind Tullahoma's payback figure
3125 heating degree days pile up here every year, so Tullahoma has a real but manageable winter; the cooling side runs to 1504 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 3.2°F, against a record low of -9.4°F. That puts the seasonal coefficient of performance at 2.78 for the recommended cold-climate unit. Below the 25°F line where a standard machine starts leaning on resistance backup, Tullahoma sits firmly in cold-climate territory, so that's the class of unit priced here. Source: NOAA station TULLAHOMA REGIONAL AIRPORT WI, 1.6 miles from Tullahoma — the closest one on record.
Tullahoma's running-cost comparison, in dollars
Electricity use for heating alone comes out to about 2,846 kWh a year on the 2000-square-foot reference house; folding in cooling puts the electric bill near $573 a year. Tullahoma's gas rate of 11.84 per Mcf, applied to the 33 Mcf a year the furnace burns, puts its running cost near $656 a year, against 13.87¢ per kWh for electricity. Buy it outright, not incrementally, and payback stretches to 162.6 years; over 15 years the net position sits $2,254 behind.
Electric resistance heat in Tullahoma, compared
Not every home in Tullahoma has gas service. Swap the comparison to resistance heat instead of gas, and Tullahoma's answer improves. The saving here runs about $795 a year, which recovers the extra $8,000 spent going electric in roughly 10.1 years.
How Tullahoma compares nationally
Ranked against the other 3206 cities covered, Tullahoma comes in at 1865 for heating severity — 1 would be the coldest place in the dataset — and 1844 by population, where 1 is largest. That's the middle third for winter severity among the cities covered here.
Deciding what's next in Tullahoma, TN
About 21,035 people live in Tullahoma, Tennessee, 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
Every constant behind this page — the 2.78 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Tullahoma's 3.2°F design temperature falls on the cold side of the 25°F cutoff the cold-climate unit guide walks through.