Can hailstones cause micro-cracks in solar panel glass?

Hail Damage Risk Factors

Solar panels are designed to withstand various environmental conditions, including hail. However, the size, speed, and angle of impact from hailstones can still cause damage. According to the International Electrotechnical Commission (IEC), a 5/8 inch (16 mm) diameter hailstone traveling at 35 mph (56 km/h) can cause moderate damage to a solar panel. In contrast, a 1 inch (25 mm) diameter hailstone at the same speed can cause severe damage.

Micro-Crack Formation

When a hailstone strikes a solar panel, it can create micro-cracks in the glass surface. These micro-cracks can be difficult to detect visually but can lead to water intrusion and further damage over time. Research has shown that even small hailstones can cause micro-cracks in solar panel glass, with a 1/4 inch (6 mm) diameter hailstone creating micro-cracks in as little as 1/16 inch (1.5 mm) of the panel’s surface.

Assessing and Mitigating Damage

To assess the risk of hail damage, solar panel owners and installers should consider the location’s hail exposure and the panel’s rating for hail resistance. Some solar panels are designed to meet specific hail test standards, such as the IEC 61215 standard. For areas prone to hail, it’s essential to choose solar panels with a high hail resistance rating and to properly install and inspect the panels for any signs of damage.