Learn if solar panels can stay in charge when the sun plays hard to get
Solar panels are most efficient in full sun, but ambient daylight is enough to generate some power.
Expect production to drop by 10% to 60% in shady and cloudy conditions.
Solar systems work when it’s cloudy, rainy, and snowy as long as the panels aren’t covered.
Solar contractors understand local climate and weather and can optimize the solar system design.
No place has sunlight 24 hours a day, 365 days a year. Clouds and rain, shade from nearby trees and buildings, and nighttime keep the sun from shining on solar arrays. But do solar panels need direct sunlight to work? Let’s shed some daylight on your solar panel questions and explore how the sunlight impacts your solar system production.
Solar panels convert sunlight into solar energy that homes and buildings can use. While they work best under direct sunlight, they still generate electricity in the shade and on cloudy days.
When panels face direct sunlight, they absorb the maximum number of photons to create more electricity. Peak sun hours occur during midday when the sun’s energy reaches optimal levels—this is when the sun works overtime.
Experienced solar panel installers near you can design systems for your location and help you learn how to increase solar power efficiency and get the most from your investment.
Here’s how to get the best efficiency possible from your solar panels:
Aim for four to six hours of direct sunlight each day
Peak sunlight hours (10 a.m. to 3 p.m.) are best
Pros can recommend efficient systems and prime locations
Choose the right panels, setup, components, and incentives
Keep solar panels clean and dust-free
Remove heavy snow for optimal performance
Trim trees to prevent excess shade
If your roof is shaded, you may wonder if your home is good for solar. After all, solar panels generate electricity at lower levels in indirect sunlight. In the early morning and late afternoon, when the sun is low, panels capture energy from ambient light and operate at 40% to 60% of peak efficiency. But even at these lower levels, you can still plug into the sun.
Partial shade from trees and buildings will slow down panel production, too. To solve this, use microinverters or power optimizers. These devices let each panel operate independently, minimizing impact from shaded areas and allowing solar panels to pour energy into homes.
Your solar contractor can help you power up when the sun’s up by suggesting different configurations, such as installing solar panels in a series versus in parallel to increase voltage or current and get more power from your panels despite fewer rays.
Solar panels can be an all-weather friend. Weather can change how much energy your panels generate, but if you plan for this, you’ll power through cloudy days and still get results.
Solar panels still do the job on cloudy days, but production can drop 10% to 60% from peak efficiency, depending on the cloud density. Thinner, high-altitude clouds have silver linings—they allow more sunlight to filter through and onto the panels, while thicker, lower clouds block more rays.
You can still benefit from solar power even with frequent cloud cover. Homeowners in some cloudy regions can cash in on incentives or higher utility rates that make solar more economically viable. However, if you want to use solar panels directly without a battery, you’ll need to know how much energy your home uses and how clouds dim output so you don’t run out of power.
Like with cloudy conditions, solar panels don’t let a little rain cramp their style. They’ll still keep the power flowing but with a reduced output. Their exact production depends on the thickness of the cloud cover and the duration of the rain.
One benefit of rainy weather is that it cleans dust and debris off the solar panels. Whether your solar panels are on the ground or the roof, this boosts efficiency when the sun comes out again. It’s not a replacement for routine visits from a local solar panel cleaning pro, but it keeps panels cleaner between maintenance services.
Live in a winter wonderland? If you do it right, you can turn that into a winter “watt-erland” for solar energy. Surprisingly, solar panels perform well in winter conditions since cooler temperatures help them operate more efficiently. However, snow can block sunlight and temporarily reduce output until it melts. Solar panel installations are designed to shed snow, but you might have to remove heavy snow for optimal performance.
If you live in a snowy region, ask your solar installer about the angle and placement of the panels to keep snow from building up and to give you the best performance year-round.
Solar panels can keep the lights on even on gloomy days. Direct sunlight boosts solar panel efficiency, but it isn’t the only way solar generates energy. When installers design systems for a specific location and home, solar can be a practical investment in areas with moderate or limited direct sunlight.
Professional solar panel installers consider factors like monocrystalline versus polycrystalline solar panels, shade, the best roof pitch for solar panels, system components, utility rates, and incentives to create effective and economical systems. So even if the sun hides, your solar panels don’t take the day off.
The rule of thumb is to install solar panels so they face in the direction of the equator. This way, they receive more sunlight to power your home with solar energy. A solar panel installation pro can consider obstacles and help plan your system.
Solar panels should get at least four to six hours of direct sunlight daily. It’s even better if sunlight reaches panels between the peak hours of 10 a.m. and 3 p.m. This is enough to power a home, depending on your solar system’s size and energy needs. Remember that panels will generate some power under cloudy skies or in the shade, and many systems compensate for lower sun exposure by drawing energy from the grid or battery storage.
The morning sun can be better for solar panels because it’s often brighter and clearer than the afternoon sun. The brighter the sun, the more energy solar panels produce. The strongest rays occur during midday, which tends to be prime time for solar energy generation. Most homes get a mix of morning and afternoon sunlight.
Covering solar panels is unnecessary when they’re not in use. Panels are weather-resistant and durable, so exposure to the elements won't cause extensive damage. In fact, covering solar panels can cause moisture buildup. If you’re away from home for a long period and cover your panels, it can protect them against dust and maintain higher production output.
