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
| City | Usable 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:
| City | Sun hrs/yr | Rate | Payback |
|---|---|---|---|
| Kahului, HI | 1,627 | 42.1¢ | 3.5 yrs |
| Baltimore, MD | 1,467 | 18.3¢ | 8.8 yrs |
| Norfolk, VA | 1,539 | 14.2¢ | 10.9 yrs |
| Oxford, South East | 1,012 | 26.1¢ | 12.9 yrs |
| Trois-Rivières, QC | 1,347 | 7.9¢ | 31.9 yrs |
Frequently asked
Do I need to clear snow off my solar panels?
Usually not. Panels are mounted at an angle and dark-surfaced, so snow tends to slide off within a day or two of sun. Climbing onto a roof in winter is far more dangerous than the output you would recover, and annual production figures already account for typical snow cover.
Do solar panels work at night?
No. They generate only from daylight, so night-time use comes from the grid or a battery. This is why export rules matter so much: you generate a surplus at midday and buy power back after dark, and the price gap between those two decides much of your saving.
Does rain damage solar panels?
No — panels are sealed and tested against water ingress and hail. Rain is mildly helpful, since it rinses off dust and pollen that would otherwise reduce output. The larger weather risks are hail severe enough to crack glass, and debris driven by high winds; insurance usually covers both.
Related guides
General information, updated 2026-08-22. Not financial, tax or engineering advice.