Ottumwa, IA: the heat pump payback math
In Ottumwa, a heat pump would cost more to run each year than what you have now. 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. The heat pump would cost about $88 more a year to run than the furnace it replaces — a premium with no payback. There's no spin on that: Ottumwa's numbers say wait.
Why Ottumwa's climate drives this number
Degree days tell the story here: Ottumwa racks up 5177 heating degree days each year (base 65°F), and summers add a moderate cooling load, with 927 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 -11°F, against a record low of -18.9°F. That puts the seasonal coefficient of performance at 2.44 for the recommended cold-climate unit. Ottumwa 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. These numbers come from OTTUMWA INDUSTRIAL AIRPORT, the closest NOAA station, 6.1 miles out.
The month-to-month numbers for Ottumwa
Electricity use for heating alone comes out to about 5,372 kWh a year on the 2000-square-foot reference house; folding in cooling puts the electric bill near $820 a year. The gas furnace it replaces burns roughly 54 Mcf a year at 10.61 per Mcf here, for a running cost near $732 a year (electricity here runs 13.31¢/kWh). Buy it outright, not incrementally, and payback stretches to beyond the 15-year equipment life; over 15 years the net position sits $4,825 behind.
Electric resistance heat in Ottumwa, compared
Not every home in Ottumwa has gas service. Compared with baseboard or electric-furnace resistance heat, the numbers shift in the heat pump’s favor. About $1,084 a year comes back this way, enough that the 7.4-year payback clears the $8,000 premium comfortably within the equipment's life.
Ottumwa against the rest of the country
Ranked against the other 3206 cities covered, Ottumwa comes in at 579 for heating severity — 1 would be the coldest place in the dataset — and 1566 by population, where 1 is largest. 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 Ottumwa
About 25,648 people live in Ottumwa, Iowa, 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 2.44 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Ottumwa's -11°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.