How to Fix Solar Panel Shading and Optimize Sunlight (4/27/2020)

Solar panel shade refers to reduced sunlight casted on part of the array or system. When exposed to shade, the power output of solar panels is greatly reduced, resulting in inefficient operation.

Article - April 27, 2020 By LarsonElectronics.com

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How to Fix Solar Panel Shading and Optimize Sunlight

Shadows from nearby trees, buildings and clouds have negative effects on solar panels. When exposed to shade, the power output of solar panels is greatly reduced, resulting in inefficient operation. Even a small amount of shade on part of the array can impose such effects on the system.

What is Solar Panel Shade?

Solar panel shade refers to reduced sunlight casted on part of the array or system. Ideally, panels should be installed in open locations. This is not always possible in commercial areas or homes next to large obstructions. Furthermore, as the angle of the sun changes during the day, exposure on the panels may vary. Without devices in place to address the effects of shading on solar panels, the overall efficiency of the system (along the string) is decreased. In some cases, shading one cell from a 36-cell module could reduce output by a whopping 75%.

Solutions for Solar Panel Shade

Installing a reliable solar inverter can help mitigate power inefficiencies and losses associated with shaded panels. With a solar micro-inverter, an inefficient panel affected by shading will not impose the same issues on other panels in the array not affected by shading (allowing them to operate at peak levels). Setting up a power optimizer device is another solution for partially shaded solar panel systems.

Bypass diodes may serve as a safety feature to ensure power flows in a single direction and prevents panels affected by solar shade from drawing the full current of the string. Focusing on the latter benefit, bypass diodes may also reduce hot spots.

Lastly, individuals may choose a location that does not experience a lot of shade during the day to avoid such operating issues. The US Department of Energy and National Renewable Energy Laboratory recommends installing solar panels via a ground or tracking mount system to maximize sunlight exposure.