It looks like the Washington DC metro area may be in for a large snowstorm this weekend, with some forecasts calling for as much as 22 inches of snow in a 24 hour period. When storms like this pop up, we reliably start hearing from homeowners who already have solar, or are considering it, asking the same question.
“My panels are going to be buried. Do I need to do anything?”
The short answer is no. Leave them alone.
Here is why.
Snow on Solar Panels Is Normal, Infrequent, and Temporary
Snowfall in the Washington DC metro area is relatively infrequent. Most winters bring only a handful of meaningful snow events, and when they do happen, snow usually sticks around for just a few days.
Solar panels are dark, smooth, and angled. They are also installed in the sunniest spot on your property, usually with little to no shade. Because of that, panels almost always melt off before the rest of the roof or yard does. It is common to see panels clear themselves while snow is still sitting everywhere else.
As sunlight hits the panels, they warm slightly and the snow slides off or melts from the bottom up. No action is required.
Trying to brush or scrape snow off panels is not recommended. It is unsafe for you, and tools can scratch the glass or damage wiring. The risk is not worth the very small amount of short term energy loss.
Winter Snow Has a Small Impact on Annual Production
Timing matters.
Snow happens in the winter, when solar production is already lower due to shorter days and a lower sun angle. A few snowy days in January or February have far less impact on annual production than losing production during long, sunny summer days.
Missing a day of production in July matters much more than missing a day in February. That is why even a big snowstorm does not meaningfully affect your system’s overall yearly output.
Snow Is Already Accounted for in Our Production Estimates
When we design your system, we are not assuming perfect weather.
Our production forecasts for the DC metro area are based on National Renewable Energy Laboratory PVWatts, which uses decades of historical weather data. That data includes snowfall, winter cloud cover, and seasonal sunlight patterns.
The model already assumes a small number of low or zero production days each year due to weather. Snow days are baked into the estimate from the start. When it snows, the system is performing exactly as modeled.
That is why short winter interruptions do not change the long term economics or savings of your system.
Solar Panels Are Engineered for Snow Load
Solar panels and mounting systems are designed to handle far more weight than a typical DC snowstorm produces, even a large one.
Before installation, a licensed structural engineer reviews your roof structure, framing, and mounting layout. They confirm that everything meets wind and snow load requirements, then they sign off on the design before permits are issued.
This is a standard part of the process, not an afterthought.
Snow sitting on panels for a few days is well within what the system is designed to handle.
Will Snow Hurt My Panels?
No.
Snow does not damage solar panels. Cold temperatures actually help panel efficiency once they are producing again. There are no moving parts, no freezing issues, and no maintenance required after a storm.
As soon as the snow melts, the system automatically resumes normal operation.
Do You Need Solar Snow Guards in DC?
For most homes in Washington DC, the answer is no.
Most residential roofs in DC are flat or low slope, and we simply do not get enough regular snowfall to justify snow guards. Snow here is infrequent, short lived, and usually melts or slides off panels quickly on its own.
There is also a real tradeoff. From our experience, snow guards can reduce overall annual solar production by roughly 5 to 8 percent by shading the bottom of panels year round. Because of that, we generally do not recommend them unless completely necessary.
The one necessary exception is for safety. If solar panels are installed directly above a main entryway or an area with regular foot traffic, snow guards may make sense to prevent snow from dropping all at once.
For the vast majority of DC area homes, snow guards are unnecessary and not worth the production loss. If you are unsure, we are always happy to review your roof layout and talk it through.
The Bottom Line
If your solar panels are covered in snow:
- Do not climb on your roof
- Do not try to scrape or brush them off
- Do not worry about short term production dips
Snow is infrequent in our area, expected in winter, and already accounted for in both the energy model and the system design.
Your panels are sitting in the sunniest spot on your property for a reason, and they will almost always melt first.
So if a big storm rolls through, do not stress about your solar system. Enjoy the snow. Make a hot chocolate, grab a sled, and let the panels do what they were designed to do.
If you ever want help reviewing your monitoring app or understanding winter production, we are always happy to walk through it with you.
