Mamaroneck, NY: the heat pump payback math
Mamaroneck 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). Running costs here land $164 a year HIGHER than the furnace it replaces, so that premium is never recovered. There's no spin on that: Mamaroneck's numbers say wait.
Why Mamaroneck's climate drives this number
Degree days tell the story here: Mamaroneck racks up 4760 heating degree days each year (base 65°F), and summers add a moderate cooling load, with 888 cooling degree days on the cooling side. Sizing runs off the design temperature, not the average day: 15.1°F here (record low 6.1°F), which works out to a seasonal COP of 3.06 for the cold-climate class of unit this climate calls for. Mamaroneck 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, WESTCHESTER COUNTY AIRPORT, 8.7 miles from Mamaroneck.
What it actually costs to run, year to year
Modelled on a typical 2000-square-foot house, the heat pump draws about 3,939 kWh a year to keep it warm, plus cooling, for a combined electric bill near $1,372 a year. The gas furnace it replaces burns roughly 50 Mcf a year at 17.58 per Mcf here, for a running cost near $1,208 a year (electricity here runs 29.22¢/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 $5,966 behind.
If your home heats with electric baseboard instead of gas
Not every home in Mamaroneck has gas service. Swap the comparison to resistance heat instead of gas, and Mamaroneck's answer improves. The saving here runs about $2,486 a year, which recovers the extra $8,000 spent going electric in roughly 3.2 years.
Mamaroneck against the rest of the country
Among 3206 cities, Mamaroneck's winter puts it at rank 983 for severity, while its size puts it at rank 1944 for population — 1 in both cases being the extreme. That's the coldest third of the dataset, where climate does most of the work behind this figure.
Next step for 19,783 people in Mamaroneck
About 19,783 people live in Mamaroneck, New York, 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.
Line up a few local HVAC quotes before you decide.
Where Mamaroneck's figure comes from
The methodology guide walks through exactly how Mamaroneck's 3.06 seasonal COP and the rest of this page's numbers get built. At a 15.1°F design temperature, Mamaroneck sits in cold-climate territory; the guide to that class of unit explains why.