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Solar panels or a heat pump first?

If you heat with gas, oil or propane, buy the heat pump first. If your home is already all-electric, buy solar first. They are not competitors — a heat pump reduces the energy you need, solar changes where your electricity comes from. Order matters because a heat pump changes how many panels you need.

They do different jobs

Heat pumpSolar panels
What it doesMoves heat efficiently — heating and coolingGenerates electricity
Typical cost$8,000–18,000$22,800 for 8 kW
CutsGas/oil use; often raises electricity useElectricity bought from the grid
Works whenAlwaysDaylight only, without a battery

Why order matters

A heat pump can add 4,000–6,000 kWh a year to your electricity use. Install solar first, size it to your current bill, then add a heat pump, and your system suddenly covers far less than you planned. Adding panels later means a second permit, a second crew visit, and possibly an inverter already at capacity.

If both are on the horizon, decide that now and size the array for the future load — not today's bill.

Gas-heated home: heat pump first

Replacing gas heating with a heat pump typically cuts both energy cost and carbon more per dollar spent than solar does, because you are removing a fuel rather than re-sourcing electricity. It also gives you cooling, which matters more each year. Then size solar for the new, higher electrical load.

All-electric home: solar first

If you already heat with electric resistance or an existing heat pump, your bill is entirely electricity — exactly what solar offsets. Here solar is the more direct saving, and a heat pump upgrade can follow.

The combination is the strong version

A heat pump running on your own solar is the cheapest heat available to a typical home. The catch is seasonal: heating demand peaks in winter when solar output is lowest. How winter output actually behaves → Grid-tied systems handle this by banking summer surplus, which makes your net metering rules important again. What those rules do →

Sizing for both

Roughly, add 5,000 kWh a year to your usage for a heat pump in a moderate climate, more in a cold one. At typical sunlight that is about 8–11 extra panels. Work out your number → Then check whether your roof holds them → before committing to either.

What this looks like in real cities

Measured rooftop data, spanning the range from fastest to slowest payback we have found:

CitySun hrs/yrRatePayback
Honolulu, HI 1,78742.1¢ 3.1 yrs
Wilmington, DE 1,51317.2¢ 9 yrs
Athens, GA 1,57314.1¢ 10.9 yrs
Eugene, OR 1,38612.4¢ 13.7 yrs
Gatineau, QC 1,2917.9¢ 33.3 yrs

See all 209 cities →

Frequently asked

Can solar panels run a heat pump?

Yes, though the timing is imperfect: heating demand peaks in winter when solar output is lowest. Grid-tied systems handle this by banking summer surplus.

Do heat pumps work in cold climates?

Modern cold-climate models operate well below -20C. Efficiency falls as it gets colder, so cold-climate homes often keep a backup heat source.

Should I get both at the same time?

If budget allows, yes - one permit, one design, one crew, and the array is sized for your real future load rather than your current bill.

Related guides

Check your own roof free →

General information, updated 2026-08-22. Not financial, tax or engineering advice.