Mount Juliet, TN: the heat pump payback math
Mount Juliet technically pencils out, but only past the point the equipment would need replacing anyway. $3,500 is what Mount Juliet would pay extra to go electric rather than replace the furnace and AC with the same again, once the $2,000 federal credit is applied. Lower bills claw that back: about $134 saved annually, for a payback of roughly 26.2 years. Mount Juliet's own numbers say this pencils out only in theory, not in practice.
The climate behind Mount Juliet's payback figure
2670 heating degree days pile up here every year, so Mount Juliet has a mild winter by US standards; the cooling side runs to 2133 cooling degree days, where summers are hot enough that cooling matters as much as heating. Sizing runs off the design temperature, not the average day: 7°F here (record low -0.9°F), which works out to a seasonal COP of 2.87 for the cold-climate class of unit this climate calls for. A cold-climate unit is the right call in Mount Juliet — below 25°F design temperature, a standard heat pump leans hard on electric-resistance backup, which erases most of the savings. These numbers come from NASHVILLE INTERNATIONAL AIRPO, the closest NOAA station, 11.4 miles out.
Mount Juliet's running-cost comparison, in dollars
Electricity use for heating alone comes out to about 2,356 kWh a year on the 2000-square-foot reference house; folding in cooling puts the electric bill near $579 a year. The gas furnace it replaces burns roughly 28 Mcf a year at 11.84 per Mcf here, for a running cost near $713 a year (electricity here runs 13.87¢/kWh). Looked at as a full purchase rather than an incremental one, payback here is roughly 101 years, leaving the 15-year total $1,495 behind.
Electric resistance heat in Mount Juliet, compared
Plenty of homes in Mount Juliet 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 $742 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 10.8 years.
Mount Juliet against the rest of the country
Among 3206 cities, Mount Juliet's winter puts it at rank 2055 for severity, while its size puts it at rank 935 for population — 1 in both cases being the extreme. That's the middle third for winter severity among the cities covered here.
Next step for 44,066 people in Mount Juliet
About 44,066 people live in Mount Juliet, Tennessee, 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.
More on how this number was built
Nothing above is a black box: the methodology guide shows the full arithmetic behind Mount Juliet's 2.87 seasonal COP and payback figure. Mount Juliet's 7°F design temperature falls on the cold side of the 25°F cutoff the cold-climate unit guide walks through.