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Do solar panels work in winter?

Yes — and cold weather actually makes panels more efficient. Panels lose about 0.3–0.4% of output per °C above 25°C, so a crisp sunny winter day can outproduce a hot summer one. What reduces winter output is shorter days, lower sun angles and snow cover — not cold.

What actually happens in winter

  • Daylight hours — the dominant factor. December has roughly half June's daylight in northern latitudes.
  • Sun angle — low winter sun travels through more atmosphere and strikes panels more obliquely.
  • Snow — a covered panel produces nothing, but panels are dark and smooth, so snow usually slides off within a day or two on a pitched roof.
  • Temperature — helps you, slightly.

Cloudy days

Panels produce roughly 10–25% of their clear-sky output under heavy cloud, because a lot of light still reaches them as diffuse radiation. This is why cloudy Germany and the UK have large, working solar fleets, and why Seattle roofs still get about 1,262 usable sun hours a year.

Annual production is what matters

Your system is sized against your annual usage, not any single month. Summer surplus offsets winter shortfall — in the US this is usually handled by net metering, which banks summer credits against winter bills. Check your utility's net metering rules, as they vary widely and have been getting less generous.

Northern cities in our data

CityUsable sun hrs/yr
Edmonton, AB 1,264
Winnipeg, MB 1,389
Minneapolis, MN 1,419
Buffalo, NY 1,372
Seattle, WA 1,262
Vancouver, BC 1,162

All of these are workable. Whether they're worth it depends on local electricity rates — see how payback works →

What this looks like in real cities

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

CitySun hrs/yrRatePayback
Boston, MA 1,44630.1¢ 5.4 yrs
Sacramento, CA 1,79631.2¢ 8.8 yrs
Myrtle Beach, SC 1,58914.2¢ 10.4 yrs
Chattanooga, TN 1,54612.1¢ 12.8 yrs
Montreal, QC 1,3847.9¢ 30.7 yrs

See all 209 cities →

Frequently asked

Do I need to clear snow off my solar panels?

Usually not. Panels are dark and smooth and typically shed snow within a day or two. Climbing on a snowy roof is far more dangerous than the lost output is valuable.

Do solar panels work at night?

No. They produce nothing without light. Night-time power comes from the grid, or from a battery charged during the day.

Does rain damage solar panels?

No. Panels are sealed and rated for weather, and rain helps by washing off dust that would otherwise reduce output.

Related guides

Check your own roof free →

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