Solar Photovoltaic Hail Prevention

Are solar PV systems prone to severe hail?

The greatest contributor to insured losses on solar PV systems worldwide is severe hail. Severe hail events are forecasted to increase in frequency over time, emphasizing the increasing importance of designing and preparing for solar PV resilience to hail. Many areas are prone to hail events, and the level of risk a site faces may not be intuitive.

How does hail damage affect photovoltaic systems?

In particular, hail damage seriously affects photovoltaic systems. The severity of hailstorms as well as impact responses are important factors in mitigating loss, so the first research area that needs to be addressed is the resistance of photovoltaic modules to hail.

Can solar PV modules survive hail?

Historically, solar photovoltaic PV modules have survived the majority of hail events they have experienced. In areas that have experienced very large hail (greater than 1 ¾" or 44 mm diameter), however, hail has caused significant damage to PV modules. Some measures can be taken to limit damage to PV modules.

Should solar panels be protected from hail?

For existing solar rooftops vulnerable to hail, some asset owners elect to install raised mesh hail guard screens above the panels to block falling hail. However, these ventilated steel or polymer shields can add hefty additional wind loads that may overwhelm rooftop load limits if not designed properly.

Are solar assets prone to hail?

Solar assets located in hail-prone regions face higher risks of damage over their 25+ year lifespan. The American Meteorological Society analyzed hail patterns across the United States from 2009 to 2018 to quantify high-exposure areas. Colorado, Nebraska, and Wyoming ranked as the top three states for hailstorm frequency and severity.

What are the best ways to protect against hail?

Take the maximum hail mitigation measures in regions prone to very severe hail (i.e., larger than a 2-inch diameter) or likely to experience greater incidence of hail (i.e., greater than 9 days per year of inch+ hail). Proactively designing a system to be hardened to hail is more effective than retrofitting it to be more robust.