Do Solar Panels Work in the Winter and Snow?
Jan 31, 2020
by EmPower Solar
Winter is officially upon us and a common question we receive is whether our solar panels work in the winter and snow. When EmPower Solar designs rooftop systems, the engineering team accounts for seasonal differences in solar production and savings so that clients receive the most accurate forecasts possible. We’ve been based here in New York for over 15 years, and are all too familiar with the unpredictable winter weather. Solar panels are installed in every climate across the world, so there are many answers to these common concerns, but today we address winter weather for solar panels when it comes to Long Island and New York City.
There are many misconceptions about solar panels in the winter. Many believe that panels don’t work in the winter, but cooler weather actually allows for a more even flow of electricity from panels into your home. Cooler temperatures enhance solar energy production efficiency, increasing the daily amount of electricity produced. The bigger factor that affects system production in winter is that we have fewer daylight hours, and the sun is lower in the sky, so more shade is created at different times of day from nearby trees, which can reduce the amount of direct sunlight hitting the panels. It is important to remember that panels create electricity from the sun’s light, not the sun’s heat.
WHAT HAPPENS WHEN IT SNOWS?
During a light snowfall, sunlight can still get to the solar panels and produce energy. In a heavy snow, solar panels will not receive enough sunlight to operate, and the system is not likely to turn on or produce any energy on those days. However, snow typically melts off of solar panels quicker than it melts off of an asphalt roof. This is possible because our engineers make sure your panels are in the best position to get the maximum amount of sunlight possible, and panels are usually installed facing the south, west or southwest. Unlike rough roof shingles, the solar panels are smooth, so the snow typically melts or slides away quickly and easily on its own. We also install ‘snow guards’ over decks, doorways, and windows that prevent snow from coming down in large chunks during melts.
SHOULD I CLEAR SNOW OFF MY SOLAR PANELS?
There are times during heavier snowfall and blizzards when the snow may pile up on your roof and solar panels. Panels won’t work at this time, but it’s only temporary. If you are, however, concerned with squeezing out every last kWh of your system, you can call our service team at 516 837 3459 (x153) to schedule a snow clearing. The cost to do so is not usually offset by production you will gain at this time of year, so we don’t always recommend it, but it is available. We also don’t recommend climbing on your roof in the snow, or using any brushes, scrapers, or other tools to clean the snow off of your panels. The solar panels are coated in a unique anti-reflective coating that can be seriously affected
by foreign objects. Product warranties do not cover damage accidentally caused by cleaning your panels.
SOLAR POWER GENERATION IN THE SUMMER VS. WINTER
When solar panels are installed on a home, the home still remains tied to the electric grid and has access to net metering. That way, the utility company can both buy excess energy and provide electricity if the solar panels can’t receive adequate sunlight. This applies to business and commercial scale installations too.
From spring through autumn, solar panels operate at their maximum capacity, and often produce more energy than a home needs in a given month. That excess energy is sent back to the grid, and the homeowner earns solar credits on their monthly utility statement. In the winter, when solar panels are not producing as much energy, homeowners can use their built-up solar credits and pull energy from the grid without necessarily having to pay for those credits. Keep in mind that this occurs mostly in systems designed to produce 100% or more of a home’s annual energy needs. Sometimes systems can only produce a portion of annual energy needs, so some energy will need to be purchased from the grid when there are no credits available.
Keep in mind, if your panels are installed right before the winter, you won’t have that summer energy bank to draw from. Once you’ve made it through the high production months and build up your credit bank, you will be able to take advantage of your energy credits next winter.
There’s snow reason not to go solar in the North East!
For more information on solar net metering, as well as a comprehensive list of FAQs, please visit the Client Corner.