Should Savannah switch to a heat pump?

A heat pump earns back its extra cost in Savannah within a sensible timeframe. Against a like-for-like gas furnace and AC swap, going electric costs $1,000 more up front here (already netting out a $2,000 tax credit). Savannah's residents would see roughly $294 a year back in running costs, putting the payback around 3.4 years. The window here is reasonable, and it's specific to what Savannah actually pays for power and gas.

How cold Savannah actually gets

1252 heating degree days pile up here every year, so Savannah barely has a winter to speak of; the cooling side runs to 2806 cooling degree days, where summers are severe enough that cooling can dominate the annual bill. Sizing runs off the design temperature, not the average day: 26.4°F here (record low 24.6°F), which works out to a seasonal COP of 2.99 for the standard class of unit this climate calls for. Savannah's winters don't get cold enough to need the cold-climate premium — a standard unit holds up fine. Source: NOAA station HUNTER ARMY AIRFIELD, 3.6 miles from Savannah — the closest one on record.

Savannah's running-cost comparison, in dollars

Modelled on a typical 2000-square-foot house, the heat pump draws about 1,060 kWh a year to keep it warm, plus cooling, for a combined electric bill near $514 a year. Savannah's gas rate of 20.42 per Mcf, applied to the 13 Mcf a year the furnace burns, puts its running cost near $808 a year, against 14.90¢ per kWh for electricity. Looked at as a full purchase rather than an incremental one, payback here is roughly 37.5 years, leaving the 15-year total $3,405 ahead.

If your home heats with electric baseboard instead of gas

Gas isn't universal in Savannah — many houses run on electric heat already. Compared with baseboard or electric-furnace resistance heat, the numbers shift in the heat pump’s favor. The saving here runs about $500 a year, which recovers the extra $5,500 spent going electric in roughly 11 years.

Savannah against the rest of the country

Among 3206 cities, Savannah's winter puts it at rank 2781 for severity, while its size puts it at rank 185 for population — 1 in both cases being the extreme. That's the mildest third of cities covered, where utility rates carry more of the answer than climate does.

What to do with this number in Savannah

Savannah, Georgia is home to about 148,808 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. Given the math above, Savannah is a place worth lining up quotes ahead of a breakdown, not waiting for one.

Line up a few local HVAC quotes before you decide.

Reading further on this page's numbers

Nothing above is a black box: the methodology guide shows the full arithmetic behind Savannah's 2.99 seasonal COP and payback figure. The $2,000 federal credit baked into Savannah's number is explained, with the before-and-after math, in the tax credit guide.