When we picture the winter season, most of us imagine our roofs buried in snow, the biting cold that lingers, and the sun barely making an appearance. And so, the idea of solar energy during this time can feel a bit counterintuitive. But contrary to popular belief, solar panels do still work in winter, which means the value of going solar doesn’t disappear — and your investment doesn’t go to waste. Read further as I walk you through the facts about what happens to solar during winter, and how they continue to produce energy even when it’s cold and overcast outside.
Do Solar Panels Work in Winter?
Yes, solar panels absolutely work in winter. As long as there’s sunlight, your panels will keep generating electricity — because what they need is light, not heat.
Side note: I’ve actually stressed this a lot in a previous article, Do Solar Panels Work on a Cloudy Day?
Here are three facts that show why winter doesn’t actually stop your system, and how, in some cases, it might even give it a bit of an edge.
Solar Panels Run on Sunlight, Not Temperature
This might be the biggest misconception out there. As I mentioned, solar panels don’t need warm weather to function. They need photons, which come from sunlight. Even in winter, the sun still shines (albeit for shorter hours), and that light is enough to keep your system going.
To put this in perspective, take a look at Minnesota and Michigan. Both states experience harsh winters, yet still rank among the top 20 solar states in the U.S., according to the Solar Energy Industries Association (SEIA).
Solar Panels Are More Efficient in Cold Weather
Building on the previous point about solar panels not needing heat to function, it might surprise you that they’re not particularly fond of high temperatures either.
In fact, excessive heat can reduce their voltage, which in turn slightly lowers their efficiency.
Most solar panels are tested at a standard temperature of 77°F (25°C), but for every degree Celsius above that, their efficiency drops slightly. This drop is measured by what’s called the temperature coefficient — usually around -0.3% to -0.5% per °C, depending on the panel brand.
For example, if your panels are operating in 30°C (86°F), that’s 5°C above the test condition of 25°C (77°F). With a temperature coefficient of -0.3% per °C, this means you’d lose about 1.5% efficiency due to the heat.
So if your panels are rated at 21% efficiency under ideal conditions, they’d drop to around 19.5% efficiency under those warmer temperatures.
In contrast, colder temperatures reduce internal resistance. That means with less heat to push against, panels convert sunlight to electricity more effectively.
The ‘Albedo Effect’ Can Actually Increase Solar Output
When sunlight hits snow-covered surfaces, that light reflects back upward — a phenomenon called the albedo effect.
That extra reflected light can bounce onto your panels and boost the amount of energy they take in. In theory, the more they absorb, the more electricity your system can generate.
Do Solar Panels Work With Snow on Them?
Yes, solar panels can still work when covered in snow — but only if the snow isn’t entirely covering them. A thin dusting probably won’t affect that much, but a heavy blanket of snow can temporarily block sunlight from reaching the panel.
Fortunately, solar panels are usually installed at an angle, so when the sun comes back out, most of the snow begins to melt and slide away on its own. Helping this along is the fact that panels are built with smooth, tempered glass, which makes it harder for snow to stick in the first place.
They also generate a bit of heat while operating, which, combined with their dark surface absorbing sunlight, helps them shed snow faster than the surrounding roof.
How Well Do Solar Panels Work in Winter?
During winter, solar panel production can drop to about 30% to 50% of a system’s rated capacity. So if your system typically produces 900 kWh in July, you might only see around 270 to 450 kWh during the colder months.
Do take that with a grain of salt, though, because how much less energy your system produces in winter depends on several factors:
- Daylight Hours: States with more peak sun hours tend to generate significantly more energy than those with fewer.
- Cloud Cover: The cloudier it gets during winter, the tougher it is for direct sunlight to break through. And when light intensity drops, so does your system’s energy production.
- Snow Cover: As mentioned, panels can occasionally get covered in snow. In rare cases where snow completely blocks sunlight, energy production ca nosedive, similar to how shading from trees or nearby structures can reduce output.
Even with all of that in mind, here’s why you shouldn’t worry.
Remember that a well-designed solar system is built to match your household’s energy use across all seasons. Combine that with net metering, and the energy your system overproduces during sunnier spring and summer months can be banked as credits to offset those dips in winter production.
So even if your panels generate a little less in the colder months, your annual performance still stays on track.
And speaking of ‘staying on track’, there are things you can do to keep your panels performing at their best during this low-yield season.
Ways to Keep Your PV Panels Performing Well in Winter
Use a Solar Snow Rake to Remove Buildup
If snow buildup is blocking light for days, you can gently remove it using a solar-safe brush or a roof rake with a soft rubber edge. Never use metal tools (like a shovel) or pressure washers as they can scratch or crack the glass surface.
Avoid Dangerous DIY
Don’t climb on an icy roof just to brush snow off panels. The energy gain isn’t worth the risk. As mentioned earlier, using a solar-safe snow rake from the ground is a much safer alternative if clearing snow becomes necessary.
Better yet, call a professional solar panel cleaning or maintenance team instead to do the job.
Trim Nearby Trees
Since the winter sun rides low, even small shadows can cut down energy production. By trimming branches in late fall, you help maximize the light your panels can catch during shorter days. This is especially important in neighborhoods with mature trees.
Consider Oversizing Your System
Slightly oversizing your system can help you generate extra energy during the sunnier months — especially useful if your utility offers net metering. Those summer overages can turn into bill credits that help offset the dip in winter production.
This, I would say, is something you shouldn’t worry so much about. Certified solar installers like us will handle your system’s sizing based on your year-round energy use.
Explore Tracking Systems (If Applicable)
While residential rooftops don’t usually come with adjustable mounts, ground-mounted systems sometimes do. Dual-axis tracking systems can tilt and rotate to follow the sun throughout the day and year — including adjusting for that low winter sun angle.
Do Solar Panels Crack in Cold Weather?
No, solar panels don’t crack in the cold winter weather since they are engineered to resist very low temperatures. In fact, they undergo rigorous testing under standards like IEC 61215 and UL 1703, which includes the Thermal Cycling Test.
Here, panels are subjected to temperature fluctuations between 40°C and +85°C for 200 cycles to simulate real-world thermal stresses.
Avail Solar proudly installs panels from REC, Hyundai, and QCells, all certified to meet these standards.
Winter Solar Works With the Right Design
Winter production dips — that’s expected. But that dip can be balanced out by the extra energy your system produces during sunnier months. It all comes down to one thing: A solar system tailored to your home’s consumption.
At Avail Solar, we build home solar systems that are ready not just for the winter, but for the entire year. Our team has installed hundreds of home solar setups across Utah, Nevada, and Colorado, all designed around seasonal shifts and real household energy needs.
Request a quote today or call us to get started