By Tim Henderson
Most people know that solar panels in the sun produce reliable energy in direct sunlight.
But what happens when it’s foggy, or overcast out? Do solar panels work in the rain? What happens in the winter, when daily sunlight hours drop? Will your solar panels still power your home?
If you think your solar panels stop working without direct sunlight, it’s time to think again. In fact, most modern versions of PV solar panels actually work more efficiently in cooler, cloudy, or overcast conditions.
After all – solar panels are meant to provide a reliable source of clean energy – rain, shine, or clouds. Because of this, they’re sensitive enough to pick up and transform various types of light, even when the sun isn’t hitting them directly.
Read on to learn more about how it works.
Wondering how solar panels work on cloudy days? To produce clean energy, solar panels must harness infrared and visible light. While it may seem like that’s easiest to do on sunny days, it’s important to remember that, even on overcast days, usable sunlight still makes its way through the clouds.
While solar panels are famous for working in direct sunlight, they’re also fantastic at capturing diffuse sunlight (sunlight that is filtered through and scattered by the clouds) and reflected sunlight, which bounces off buildings or the ground before making it to the surface of your panels. While solar panel cloudy day output is less than normal, it’s still ample enough to make a significant difference in your home.
Here are a few things you should know about why solar panels are so good at collecting light on cloudy days:
Visible Light Permeates Clouds. Even on dreary, rainy days, visible light still comes through the clouds. Even if the light is minimal or very dark, solar panels are sensitive enough to capture that light and convert it to energy for your home or business
Infrared Light Comes Through Clouds Easier Than Clear Skies. Infrared light permeates clouds more easily than it does clear skies. This is because infrared light has a longer wavelength than visible light.
Just like it’s possible for your skin to pick up UV light on a cloudy day, it’s also possible for solar panels to generate electricity on cloudy days. Even though diffuse and reflected light is less powerful than direct sunlight, it provides ample energy to help power your home.
Still not convinced that solar panels work well on cloudy days? Here are some statistics to back it up:
While New York gets less sunlight than 18 of the 25 top cities for solar, it has one of the highest utilization rates in the country. In fact, solar panel adoption in the city has quadrupled since 2014. New York is currently aiming for a solar capacity of 1,000 MW by 2030. This solar capacity would be enough to power about 250,000 households.
The UK is famous for its wet, overcast weather, and yet the region has continued to increase its solar energy production in recent years. As evidence of this growing market, major companies like Ikea have recently debuted solar energy storage systems and solar batteries for the home throughout the U.K.
Germany has a cold, rainy climate with many overcast days. In fact, the country only gets as much sun each year as famously overcast Alaska! Regardless of that, however, Germany supplies upwards of 85% of its electricity through renewables, with a significant portion of that owing to its more than 1.5 million solar installations throughout. All told, the country has more than five times as many solar panels as the U.S.
Solar power systems aren’t meant to work on a day-by-day basis. Instead, solar panels for home use work on the overall economy of an environment. Because of this, the total amount of sun a system receives annually is much more important than its daily hours of sun. As such, total annual output can be significant, even in overcast climates.
Because solar panels are sensitive enough to pick up all types of light – even diffuse, weak, or reflected light – they’re ideal for use in climates that don’t get a lot of sun, or where rain and fog are common.
By reducing a household’s overall grid electricity cost, solar panels help U.S. families and businesses enjoy a higher quality of life and the peace of mind that comes with knowing the energy they’re producing is green.
For more information about residential solar panels or to find out how you can get solar panels for your home, contact Sandbar Solar. As the largest residential and commercial solar installer in Santa Cruz County, Sandbar Solar & Electric promises you can count on our commitment to quality work, ethical solutions, community sponsorship, and environmental stewardship.
Our reputation precedes us! We’re proud to design and install the most efficient solar panels on the Central Coast. We invite you to look through our online portfolio to learn more.
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Tim has worked in the solar industry since 2008. He has a Master's Degree in Energy Resources Engineering from Stanford University. His years of experience include working on solar energy projects for both homes and commercial properties. Tim enjoys sharing his knowledge of this evolving industry and making a difference in his community.
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