Can a Solar Array Be Damaged by Nearby Lightning?

Lightning Protection Considerations

When designing a solar array, it’s essential to consider the risk of lightning strikes. The likelihood of a lightning strike depends on the array’s location, size, and height. For example, a 1 MW solar array installed in a region with a high lightning density (such as Florida) should be designed to withstand a 100-year return period lightning strike. This typically involves installing surge protection devices, grounding the array, and using lightning-resistant materials.

Surge Protection Devices

Surge protection devices (SPDs) are an effective way to protect a solar array from power surges caused by lightning strikes. SPDs can be installed at the array’s inverter, DC-DC converter, or even at the solar panel level. The choice of SPD depends on the array’s voltage and current ratings. For example, a 1 MW solar array with a 1000 V DC system might require a 1000 V DC SPD with a 100 kA surge current rating.

Installation and Grounding Techniques

Proper installation and grounding techniques are crucial to preventing lightning damage to a solar array. The array should be installed with a grounding system that meets or exceeds local building codes and industry standards (such as NFPA 780). This typically involves installing a grounding electrode (such as a grounding rod) and connecting it to the array’s metal components, including the inverter, DC-DC converter, and solar panels.