How to Protect Solar Infrastructure from Hail Damage

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Hail damage to solar projects is like Kryptonite to Superman.  It is estimated that a whopping 40% of recent solar infrastructure damage has been caused by convective storm events that produce hail.  And unfortunately, most large-scale solar hail losses have occurred in the U.S.  The good news is that there are things that solar-project owners/operators can do to help reduce the risk.

Mitigation Steps for Hail Damage

According to a division of the National Oceanic and Atmospheric Administration (NOAA), over 26,000 storms with hailstones of at least 50 millimeters have been recorded in the past 75 years or so.  There were 630 such events recorded in 2022 (the most recent data available).

That said, these large-hailstone events make up only 10% of all hailstorms recorded in the U.S., and therefore the risk of a solar project experiencing hail damage is greater than what you might expect (and growing because the frequency of hailstorms and the average hailstone size is trending up).  For example, in 2019 a hailstorm caused at least $70 million in damage to the Midway Solar Project in Texas.  This is clearly no joke.

According to this article from powermag.com, here are 3 best-practice mitigation tactics:

• Utilize solar panel glass that has undergone strengthening measures such as heat strengthening or chemical tampering, which should make them twice as resistant to hail damage.
• Use thicker glass – the thicker the panels, the more resistant they will be. Aim for a thickness of at least 4 millimeters.
• Consider the deployment of a solar panel tracking system equipped with a hail stowage mechanism. This allows the panels to be rotated to a more vertical position when hail is expected, reducing the exposed surface area.

As the percentage of solar capacity in the overall energy mix continues to expand, it is important to “harden” this infrastructure as much as possible.  And because solar panels are made out of glass, protecting them from various forms of blunt-force trauma like hail damage must be priority #1.