Modern Solar panels are very sturdy and are designed to handle the rigors of multiple environments. They can cope with punishing heat (Phoenix, Las Vegas etc) and severe cold (Chicago, Fargo, Anchorage etc), wind, hail, heavy rain, snow, and sunshine for many years. However, it is important to understand the effects that weather can have on solar panels so that you can get the most out of your system. For instance, shade is a weather condition that clearly impacts your panels. The output is significantly reduced when it is in the shade. That said, shade will obviously not damage the panels.
Solar Panels and Testing
Solar panels go through rigorous testing based on certain standards and tend to meet CSA, IEC/EN, UL, and ISO standards and certification. Industry tests are conducted in a variety of different ways. These are important not just in terms of your panels’ resistance to the weather, but also in terms of your financial return. You must comply with local building codes before you can receive state rebates, for instance. Usually, this is NFPA 70 (the National Electric Code), which specifies that your panel must be UL certified. However, UL certification itself is often not specified, which does somewhat confuse the matter.
Wind, Lightning, and Hail Damage
It is possible for a solar panel to sustain damage as a result of a heavy hailstorm. Fortunately, this is very rare. Usually, panels are UL listed, which means that they have passed hail tests. The aim of this test, however, is to make sure the glass doesn’t explode as a result of hail impact and thereby put people in danger. It may, therefore, break and still pass the UL test. The test involves striking a panel with a 1″ steel ball at terminal velocity and a 90 degree angle. Check out this link from Renewable Energy World highlighting severe hail damage: https://www.renewableenergyworld.com/solar/community-solar/solar-farm-pelted-by-giant-hail-as-severe-storm-ripped-through-nebraska/
Lightning, meanwhile, could feasibly damage panels as well. The National Electric Code mandates that panels are properly grounded. However, if lightning strikes, there is nothing that can guarantee 100% protection. In the rare instance lightning strikes a panel directly, the cells of the panel can be melted. Indirect strikes will cause a high voltage surge that will short out internal components. Fortunately these incidents are rare.
Wind damage, meanwhile, has also proven to be incredibly rare. In fact, during Hurricane Sandy in October 2012, most solar panels were left undamaged. The panels that did sustain damage were not installed by reputable and registered solar installers. Rather, the panels were not mounted properly, either on the ground or on the roof. Always verify that your installer is using the most current racking and that it is installed according to current building codes.
The Underwriters Laboratories (UL) has reported that most failures on solar panels happen when they have to withstand heat and cold cycles in an environment that is humid. The UL had conducted a 10-day humidity freeze test, in which panels are exposed to 85% humidity, which is similar to that in the tropics. After that, they are exposed to a -40 degrees Celsius environment. This can cause damage to the panels, but these are also environmental conditions that are almost never experienced on the planet.
Warranties and Weather Damage
Usually, the warranty that is provided for your solar panel will not cover wind, lightning, or hail damage. However, your home insurance should cover that. This is why it is vital that you keep your policy up to date.
