Should Decatur switch to a heat pump?

This one's marginal in Decatur: it only clears if you stay long enough. 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). Lower bills claw that back: about $344 saved annually, for a payback of roughly 10.2 years. It's a genuine toss-up here — Decatur's numbers don't point clearly either way.

How cold Decatur actually gets

Decatur has a mild winter by US standards — 2569 heating degree days a year against a 65°F base — and summers are hot enough that cooling matters as much as heating, at 1846 cooling degree days. 12°F is the figure equipment gets sized against here — the 99th-percentile cold snap, not an average day — with a record low of 10.9°F on file. Worked through the model, that's a seasonal COP of 2.99 on the cold-climate unit fit for this climate. Below the 25°F line where a standard machine starts leaning on resistance backup, Decatur sits firmly in cold-climate territory, so that's the class of unit priced here. These numbers come from DEKALB-PEACHTREE AIRPORT, the closest NOAA station, 7.2 miles out.

Decatur's running-cost comparison, in dollars

Modelled on a typical 2000-square-foot house, the heat pump draws about 2,176 kWh a year to keep it warm, plus cooling, for a combined electric bill near $559 a year. The gas furnace it replaces burns roughly 27 Mcf a year at 20.42 per Mcf here, for a running cost near $903 a year (electricity here runs 14.90¢/kWh). Looked at as a full purchase rather than an incremental one, payback here is roughly 39.2 years, leaving the 15-year total $1,662 ahead.

The other scenario: no gas furnace to begin with

Plenty of homes in Decatur heat with electricity alone, no gas line involved. Compared with baseboard or electric-furnace resistance heat, the numbers shift in the heat pump’s favor. About $767 a year comes back this way, enough that the 10.4-year payback clears the $8,000 premium comfortably within the equipment's life.

Where Decatur ranks in this dataset

Ranked against the other 3206 cities covered, Decatur comes in at 2112 for heating severity — 1 would be the coldest place in the dataset — and 1638 by population, where 1 is largest. That's the middle third for winter severity among the cities covered here.

Next step for 24,482 people in Decatur

Decatur, Georgia is home to about 24,482 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 Decatur, nothing is lost by holding off until the current equipment genuinely fails.

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

More on how this number was built

The methodology guide walks through exactly how Decatur's 2.99 seasonal COP and the rest of this page's numbers get built. At a 12°F design temperature, Decatur sits in cold-climate territory; the guide to that class of unit explains why.