Solar 101
Do solar panels work in winter or cloudy weather?
Yes. Solar panels work in winter, in the rain, on cloudy days, and at every temperature you'd find on a Texas roof. Cold weather actually makes panels more efficient. The two things that matter for your annual production are total daylight hours and how often clouds block direct sunlight — neither of which is a problem in any market we serve.
Why cold panels produce more
Solar cells are semiconductors. Semiconductor efficiency rises as temperature drops. A panel rated at 400W on a 77°F (25°C) lab bench can produce 5-10% more on a clear winter day at 40°F, because the silicon is operating closer to its ideal electrical state. The opposite is true in summer — the same panel might produce slightly less than its rated wattage on a 110°F roof, even with the sun directly overhead.
What clouds actually do
Clouds reduce the amount of direct sunlight reaching the panel, but they don't stop production. Diffuse and scattered light still excites the cells. Typical output on cloudy days:
| Conditions | Approximate output |
|---|---|
| Clear sky, mid-day | 100% of rated |
| Light haze / thin clouds | 70–85% |
| Heavy overcast | 20–40% |
| Rain | 10–20% |
| Light snow on panels | 0–10% until it slides off |
Texas winter math
Texas averages 230+ sunny days per year. December has about 9.5 hours of daylight in Houston (vs. 14 hours in June). So your December production will be roughly 50-60% of your June production — but every system we design is sized to your annual usage, so the year-over-year math still works out.
Common questions
Frequently asked
- Do panels still work covered in snow?
- Snow blocks production until it slides or melts off, which usually happens within a day or two. The dark glass surface absorbs heat quickly. In Texas this is rarely a factor — snow events are uncommon and brief.
- Does hail damage solar panels?
- Tier-1 panels are tested to withstand 1" diameter hail at 50 mph. They're built tougher than the asphalt shingles around them. Manufacturer warranties cover hail damage.
- Will a hot roof reduce production?
- Slightly — panel efficiency drops about 0.4% per °C above the 25°C rating. On a 110°F roof you might lose 5-8% relative to a cool morning. Annual production estimates already account for this.