One of the most frequent question we get about solar is "does solar work in the winter?" The answer is yes, even in blustery New England.
Many people are shocked to hear that solar panels work in winter weather, especially with the Northeast’s frequent snowstorms. And it’s true that because of shorter days and snow cover, a solar system’s output can be lower than on a long summer day. However, thanks to solar panels’ increased efficiency in colder months and the surplus of energy produced in the summer, your solar system will generate power and achieve its estimated output as it continues to work during the winter.
Solar panels are a resilient and reliable source of energy all year long, and are actually more efficient in colder temperatures. We at ReVision Energy have been installing solar arrays in New England for 20 years and we know how winter and solar interact. During our free site evaluation, we use sophisticated solar path modeling equipment to estimate how much solar energy your roof or yard receives. Depending on your exact location, we ‘de-rate’ the predicted annual output based on the average amount of snow your region receives. While there will always be seasonal variations, over the course of your 40+ year solar investment, your system should produce very close to our estimate.
Technical excellence is a key value at our company. Though some solar installers are tempted to be a bit...optimistic...with their production numbers, we prefer to give more conservative figures when we calculate your potential system and savings. (You can do this too with our Solar Calculator!) We would rather have your solar array outperform our estimates rather than underperform.
It's important to note that because solar energy output is tracked on an annual basis (thanks to net metering), you stand to benefit from the higher overall summer output vs. winter. Since you always have the grid for a back-up, real-time 100% solar power to your home from your panels in winter is not critical.
Even in the nastiest of winters, solar is a solid investment with numerous benefits for you and your community. Additionally, if you pair solar with a battery backup, your home can thrive in the winter, even during a famous New England winter power outage.
Yes! Many people are surprised to learn that solar panels in winter conditions can actually improve their performance, further minimizing the drop in production due to snow on the panel or the loss of daylight hours. The photovoltaic (PV) technology in solar panels is able to more efficiently convert sunlight to power when it is colder. We have a whole blog post about this, if you're interested in learning more.
Further still, snow reflects additional sunlight onto your panels, increasing the amount of energy your system is able to generate on any given day.
When a solar panel is covered with snow, it cannot produce electricity. However, solar arrays tend to shed snow pretty well—the panels themselves absorb the sun’s heat as well as its light, they are mounted to face the sun, and are often on a slope.
While it’s true that solar panels drop in production when they’re covered with snow, the percentage of overall yearly production lost is actually very small, which still makes them a good investment for prospective customers.
We do not recommend that owners of solar systems clear the snow from their arrays as this could damage the array and is not covered under the warranty. Additionally, the panels themselves tend to be in difficult or even dangerous areas to access on the roof.
If your roof and panels are covered in snow, no need to panic. When the sun reemerges after a storm, sunlight will hit the snow on your roof and cause it to shed from the panels fairly quickly. Additionally, our solar panels are built to withstand heavy weather and piles of snow. So no need to try to get the snow off your roof. We think your time is better spent indoors enjoying a cup of hot chocolate and looking forward to the next sunny day!
Here is a picture showing a large rooftop array "shedding" its snow on a sunny day:
Some customers have solar arrays that are easy to access and are willing to put in some effort to optimize their system for every possible ounce of performance. If you fall into this camp, here are a few tips. If you have a roof rake, use it to clear the area beneath the panels so that snow has a place to slide to when it sheds from the panels.
Be careful! While customers have reported success using this technique, any damage caused to your panels will not be covered under warranty. Absolutely do not try to clear the snow from collectors with the sharp edge of a metal roof rake (and never use any type of rake on evacuated tube collectors). Also, be mindful of your safety—a few extra hours of production in the shortest daylight times of year are not worth you injuring yourself.
We’ve seen that even in the nastiest of winters, solar is a solid investment with numerous benefits for you and your community. It is an abundant resource with many different implementations, and one that heats and cools your home and even works in the winter. Additionally, if you pair solar with a battery backup, your home can thrive in the winter, even during a famous New England winter power outage.
Essentially, aside from saving you money on your electric bill solar can do it all, and turn your house into a more sustainable, low impact home.