Rexburg, ID: the heat pump payback math
Rexburg 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 $271 more a year to run than the furnace it replaces — a premium with no payback. That's Rexburg's own climate and rates talking, not a hedge or a caveat.
How cold Rexburg actually gets
7231 heating degree days pile up here every year, so Rexburg has one of the harshest winters in the country; the cooling side runs to 385 cooling degree days, where summers add a moderate cooling load. Sizing runs off the design temperature, not the average day: -2.9°F here (record low -17°F), which works out to a seasonal COP of 2.63 for the cold-climate class of unit this climate calls for. Rexburg 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, REXBURG-MADISON COUNTY APT, 1.1 miles from Rexburg.
What it actually costs to run, year to year
Electricity use for heating alone comes out to about 6,962 kWh a year on the 2000-square-foot reference house; folding in cooling puts the electric bill near $913 a year. That compares with roughly 75 Mcf a year of gas at Rexburg's 7.69 per-Mcf rate — about $642 a year — against a local electricity rate of 12.52¢/kWh. Buy it outright, not incrementally, and payback stretches to beyond the 15-year equipment life; over 15 years the net position sits $7,567 behind.
Electric resistance heat in Rexburg, compared
Plenty of homes in Rexburg 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. Switching saves about $1,442 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 5.5 years.
Where Rexburg ranks in this dataset
Rexburg lands at position 39 out of 3206 cities on heating severity (coldest is 1), and 1010 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 Rexburg
Rexburg, Idaho is home to about 40,695 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 Rexburg, nothing is lost by holding off until the current equipment genuinely fails.
Line up a few local HVAC quotes before you decide.
More on how this number was built
Every constant behind this page — the 2.63 seasonal COP, the degree-day corrections, the equipment costs — is documented in the methodology guide. Rexburg's -2.9°F design temperature falls on the cold side of the 25°F cutoff the cold-climate unit guide walks through.