In sunny California, solar panels work hard to turn every ray of sunlight into electricity throughout the year. As the seasons change, the amount of electricity your panels generate changes, too. These natural variations happen because of three main factors: the sun's position in the sky, the number of daylight hours, and local weather patterns. With so much to consider, it’s important to find a solar partner you can trust to help you understand how seasonal changes impact your system’s performance.
Learning about these seasonal changes helps you get the most value from your solar investment. Let's break down how each season affects your solar panels and what you can expect throughout the year. This will help you:
- Plan your home's energy usage effectively
- Prepare for seasonal changes
- Get the most value from your solar system
Solar Production Throughout The Seasons
Think of your solar system's energy production like a wave that peaks in summer and dips in winter. During peak summer months (July to August), your solar panels will typically produce the most energy. As we move into the colder seasons, production can decrease by 40-60%, especially in areas that see more cloudy days.
These changes happen gradually throughout the year, where you’ll see average production levels in the spring and fall. In Southern California, where clear skies are the norm, homeowners will likely see more consistent production than those in the Bay Area. Even with these seasonal variations, California homes typically generate enough solar power throughout the year to significantly reduce their energy bills.
The Sun's Angle
With the changing seasons, the angle of the sun actually changes because of the tilt of the earth, and this affects how much energy your panels produce. You can think of it like pointing a flashlight straight at a wall versus pointing it at an angle. The more direct the sunlight, the more power your panels generate.
During the winter, even during peak daylight hours, around noon, the sun sits much lower in the sky. This means there is less direct contact between the sun’s rays and your panels, resulting in lower production. Less contact with the sun means less energy production.
Daylight Hours
In the dark days of winter, you might be missing those long summer evenings and your solar panels miss them too. During summer, your panels capture sunlight well into the evening hours, maximizing power generation. Come winter, when we find ourselves turning on the lights by five p.m., your panels naturally have less time to generate power.
To put this in perspective, a summer day in California gives your panels about 14 hours of sunlight, while winter days can be as low as 9 hours of sunlight. Unsurprisingly, this difference in daylight hours plays a big role in your system's output.
Weather
Winter usually brings more clouds and occasional storms that can impact your solar production. While most of California doesn't typically deal with heavy snow like other states (excluding mountain areas like Big Bear and Lake Tahoe), cloudy days and rain can temporarily reduce your system's output. While rainy days mean less production, there is a silver lining– rain helps keep your panels clean, improving their efficiency when the sun returns.
If you live in California's mountain regions where snow is common, there are a few extra things to keep in mind. A light dusting of snow usually isn't a problem; even with a thin layer of snow, your panels can still generate power. When heavier snow does accumulate, like in Mammoth Lakes, where annual snowfall is above 300 inches, your solar production will decrease, but the sleek surface and angle of your panels will help the snow clear.
Temperature
Like most technology, solar panels have an optimal operating temperature–around 77°F. When temperatures swing higher or lower, your panels' efficiency might decrease slightly, around 0.3% to 0.5% per degree, kind of like how we tend to slow down a bit on really hot or cold days.
The good news is that California, known for warm rays, blue skies, and moderate climate, helps keep these temperature-related changes minimal compared to other states with more extreme weather.
Making the Most of Your Solar System
Understanding these seasonal patterns helps you make smart energy choices throughout the year. When you know what to expect from your system each season, you can better plan your energy usage and get the most value from your solar investment. This might mean running certain appliances during peak production hours or considering solar storage options. To learn more about designing a system that fits your energy needs year-round, read our guide on whether to size your solar panels for summer or winter.
While the seasonal factors of solar panel production may seem daunting, states like California generally bode for a better year-round energy output. Due to its more moderate temperatures and general lack of major cold weather events like sleet and snow storms, the variability in energy production from solar panels is much more minor.
Solar Experts All Year
At Citadel Roofing & Solar, we’re here for you year-round. We design every solar system tailored to your unique home so you can maximize your solar investment throughout every season. Citadel has been recognized as one of the top solar companies in the nation, a reflection of our commitment to excellence and customer satisfaction. Our team can help you understand everything from seasonal production patterns to net metering credits. Give us a call today for a free consultation.
