Lilburn, GA: the heat pump payback math
Lilburn sits right on the fence — how long you'll own the house decides this one. Swap a failed furnace and AC for a heat pump rather than buying like-for-like, and the extra cost here runs $3,500 after a $2,000 federal tax credit. Lilburn's residents would see roughly $344 a year back in running costs, putting the payback around 10.2 years. It's a genuine toss-up here — Lilburn's numbers don't point clearly either way.
Lilburn's weather, in the numbers that matter
Degree days tell the story here: Lilburn racks up 2569 heating degree days each year (base 65°F), and summers are hot enough that cooling matters as much as heating, with 1846 cooling degree days on the cooling side. Sizing runs off the design temperature, not the average day: 12°F here (record low 10.9°F), which works out to a seasonal COP of 2.99 for the cold-climate class of unit this climate calls for. A cold-climate unit is the right call in Lilburn — 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 DEKALB-PEACHTREE AIRPORT, the closest NOAA station, 9.5 miles out.
What it actually costs to run, year to year
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. Lilburn's gas rate of 20.42 per Mcf, applied to the 27 Mcf a year the furnace burns, puts its running cost near $903 a year, against 14.90¢ per kWh for electricity. Buy it outright, not incrementally, and payback stretches to 39.2 years; over 15 years the net position sits $1,662 ahead.
The other scenario: no gas furnace to begin with
Not every home in Lilburn has gas service. Swap the comparison to resistance heat instead of gas, and Lilburn's answer improves. Switching saves about $767 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 10.4 years.
Lilburn against the rest of the country
Ranked against the other 3206 cities covered, Lilburn comes in at 2114 for heating severity — 1 would be the coldest place in the dataset — and 2276 by population, where 1 is largest. That's the middle third for winter severity among the cities covered here.
What to do with this number in Lilburn
Lilburn, Georgia is home to about 16,210 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 Lilburn, nothing is lost by holding off until the current equipment genuinely fails.
Get quotes from local HVAC contractors before deciding.
Reading further on this page's numbers
The methodology guide walks through exactly how Lilburn's 2.99 seasonal COP and the rest of this page's numbers get built. Lilburn's 12°F design temperature is below the 25°F line, which is why a cold-climate unit is the right call here — see what that changes in the cold-climate unit guide.