Is a heat pump worth it in Butte-Silver Bow?

Here in Butte-Silver Bow, 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). Running costs here land $460 a year HIGHER than the furnace it replaces, so that premium is never recovered. That's Butte-Silver Bow's own climate and rates talking, not a hedge or a caveat.

How cold Butte-Silver Bow actually gets

8472 heating degree days pile up here every year, so Butte-Silver Bow has one of the harshest winters in the country; the cooling side runs to 190 cooling degree days, where summers rarely ask much of an air conditioner. -27°F is the figure equipment gets sized against here — the 99th-percentile cold snap, not an average day — with a record low of -45°F on file. Worked through the model, that's a seasonal COP of 2.3 on the cold-climate unit fit for this climate. Butte-Silver Bow 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. Climate figures trace to the nearest NOAA station, BERT MOONEY AIRPORT, 9 miles from Butte-Silver Bow.

The month-to-month numbers for Butte-Silver Bow

Modelled on a typical 2000-square-foot house, the heat pump draws about 9,327 kWh a year to keep it warm, plus cooling, for a combined electric bill near $1,287 a year. Butte-Silver Bow's gas rate of 8.99 per Mcf, applied to the 88 Mcf a year the furnace burns, puts its running cost near $827 a year, against 13.56¢ 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 $10,402 behind.

The other scenario: no gas furnace to begin with

Not every home in Butte-Silver Bow has gas service. 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 $1,656 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 4.8 years.

Butte-Silver Bow against the rest of the country

Butte-Silver Bow lands at position 8 out of 3206 cities on heating severity (coldest is 1), and 1158 out of 3206 by population size (biggest is 1). 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 Butte-Silver Bow

Butte-Silver Bow, Montana is home to about 35,480 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 Butte-Silver Bow, nothing is lost by holding off until the current equipment genuinely fails.

Ask a local HVAC contractor for a quote before committing either way.

Reading further on this page's numbers

Nothing above is a black box: the methodology guide shows the full arithmetic behind Butte-Silver Bow's 2.3 seasonal COP and payback figure. Butte-Silver Bow's -27°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.