New alert system offers PV operators safeguard against hail damage

A report published in July by insurance firm AXIS Capital revealed that hail damage accounts for 55% of extreme weather-related claim costs for solar facilities in the US and Canada, with the average claim standing at US$58 million.

“This is a billion-dollar problem for the fast-growing industry. Hail may be impossible to stop, but with the right tools, we can see it coming and act decisively,” said Scott Mackaro, director of innovation and forecasting at Vaisala Xweather. “For solar operators, that’s the difference between a short-term decrease in output and a multi-million-dollar loss and lengthy downtime.”

The new feature in Vaisala Xweather combines traditional radar observations with proprietary lightning data to enable a precise hail alert up to one hour before the storm hits. According to Vaisala, hail always forms in thunderstorms, so tracking spikes in lightning activity offers an early indication of intensifying updrafts that lead to hail.

Vaisala said the new capability also offered an integration with solar tracking systems to enable operators to stow solar panels automatically when a hailstorm approaches. Many tracker systems now offer a ‘hail stow’ setting that rotates panels to a position that makes them less vulnerable to hailstone strikes. AXIS Capital estimates that a proper stow strategy can reduce hail-related damage claims by US$230,00 per megawatt.

“Every second counts when hail approaches,” said Jon Previtali, vice president at risk assessment advisory firm VDE Americas. “Though the solar industry has historically had a blind spot for implementing defences against hail, we now have proof that hail defences work as intended to prevent losses.”

Read a full interview with Jon Previtali on the growing problem of hail damage on PV Tech Premium here (subscription required).