Pewaukee, WI: the heat pump payback math

Here in Pewaukee, 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 $438 more a year to run than the furnace it replaces — a premium with no payback. There's no spin on that: Pewaukee's numbers say wait.

The climate behind Pewaukee's payback figure

Degree days tell the story here: Pewaukee racks up 6294 heating degree days each year (base 65°F), and summers add a moderate cooling load, with 394 cooling degree days on the cooling side. Sizing runs off the design temperature, not the average day: -5.8°F here (record low -11.2°F), which works out to a seasonal COP of 2.56 for the cold-climate class of unit this climate calls for. A cold-climate unit is the right call in Pewaukee — 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, WAUKESHA COUNTY AIRPORT, 1.8 miles from Pewaukee.

What it actually costs to run, year to year

A 2000-square-foot house here would pull roughly 6,225 heating kilowatt-hours annually on top of cooling, totalling about $1,238 a year on electricity. That compares with roughly 66 Mcf a year of gas at Pewaukee's 10.74 per-Mcf rate — about $800 a year — against a local electricity rate of 18.87¢/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 $10,067 behind.

If your home heats with electric baseboard instead of gas

Gas isn't universal in Pewaukee — many houses run on electric heat already. Against electric-resistance heat — baseboard or an electric furnace, both 100% efficient but still just resistance — the case for switching gets stronger here. Switching saves about $1,866 a year here — a heat pump moving heat rather than generating it needs far less electricity than resistance coils — so the extra $8,000 spent up front comes back in about 4.3 years.

Pewaukee against the rest of the country

Ranked against the other 3206 cities covered, Pewaukee comes in at 121 for heating severity — 1 would be the coldest place in the dataset — and 2257 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 Pewaukee

About 16,437 people live in Pewaukee, Wisconsin, 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 2.56 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. At a -5.8°F design temperature, Pewaukee sits in cold-climate territory; the guide to that class of unit explains why.