According to the conclusions of the Dutch researchers, damage to solar panels occurs primarily withhailstones with a maximum size of at least 3 cm."Larger hailstones(more than 4 cm) cause moredamage on average than smaller hailstones, but they also show greater variety in the amount ofdamage to solar panels" they explained in the paper"The vulnerability of solar panels to hail."

Starting at 3 cm, both invisible and visible damage can occur, but starting at 4 cm, the percentage ofvisible damage increases significantly.

The smallest cracks (microcracks) do not form in the front glass layer but in the silicon, resulting inno reduction of the initial yield. After a few months, however, the damaged areas may begin to show arapid drop in power, and after about a year the micro-cracks also become visible on the outside of thepanel.All damage then reduces the lifespan of a photovoltaic module.

The orientation of the roof relative to the direction of the hail can greatly affect the damage causedby hail to 550W solar panels, the researchers explained, noting that this factor could be even more decisivethan the size of the hailstones.

Then there is some empirical evidence - on the other hand, not too significant - that even the angleat which the solar panels are installed can influence the damage to the solar panels. A greaterinclination, according to the conclusions of the scientists, would help to moderate the damage.

The study also shows that the frequency of hailstorms is increasing in Europe and the Netherlands, as is the damage caused by hailstorms.This indicates that exposed items, such assolar panels, could become more vulnerable in the future.

"Hail risk and the vulnerability of solar panels to hail should be included in risk models and climateadaptation strategies," the Dutch researchers concluded.