If you have solar panels you should know if your modules are hail resistant. In May 2017, a major hail storm hit the town of Lakewood, Colorado. Hail, up to 7 centimeters, destroys cars, breaks windows and causes numerous injuries to people and animals. They are ruining the Colorado Mills Mall, which was closed for the entire year as a result of these events!
Are photovoltaic panels resistant to hail?
A few kilometers from the shabby building, a photovoltaic farm of the National Renewable Energy Laboratory (NREL) is being subjected to a fire test under the impact of hail of similar size. Of the 3,168 solar panels, only one was destroyed . After the storm passed, the farm continued to work without hindrance.
Good quality photovoltaic panels provide electricity for years, enduring high temperatures in summer, frost in winter, strong winds and, as you can see, strong hail storms. But how will it be in your case? Is hail a real threat? What harm can it cause and how to prepare for it? How to identify hail resistant solar panels?
Solar panels: a threat to hail?
For starters, the frequency of hailstorms varies from place to place. Here and there they are quite common, while in other places, sometimes even close, they are rare. The degree of danger of hail can be estimated on the basis of traces of hail marked on the map.
So if your house is in the yellow or red zone, you will probably want to invest in solar panels with higher mechanical strength. If, on the other hand, you live in the white zone, there is nothing to worry about. While it is always unfortunate, devastating hail storms are highly unlikely to occur.
Second, it is quite obvious that hailstorms vary in size and hailstorms vary in intensity. And although no panel in the world can truly survive record hail (a diameter of 15 cm was found in 1970), most hail storms pose no serious threat.
Solar Park Case Study by TÜV Rheinland
The report ” PV Module Failure Rating in the Field ” ( PV Module Failure Assessment in the Field ) produced by TÜV Rheinland, sets the example of data collected from PV farms in operation “lightning, storms and hail cause loss of energy only in case 10% power plant modules and seems to reduce the total power of the system by less than 1% “.
It is also worth knowing that even if the glass remains intact, microcracks can appear in the bonds under the influence of impact, which in turn can lead to snail paths. However, its appearance depends on several other factors, including the quality of the EVA sheet. We discuss them in more detail in this article , and here we will discuss the resistance of panels to glass cracks caused by hail.
Resistance of photovoltaic panels to hail
The customer must have access to the knowledge of which panels are resistant to hail and the manufacturer’s warranties must be confirmed by external companies. For this, a series of certificates were created that define the minimum resistance to hail .
The most important certificate is the international IEC 61215 . The panels with it support 25 mm hail falling at a speed of 23 m / s, which corresponds to a class 2 hail resistance (5-point scale used mainly in western countries). All solar panels sold in Poland and the European Union must have this certification, which means that all solar panels are resistant to hail , at least to some extent.
Some manufacturers claim to have greater resistance to hail. For example, Selfa in the technical sheet of its panels provides the force of a hail ball with a diameter of 55 mm at a speed of 33.9 m / s. In turn, the plates photovoltaics Tesla are characterized by their resistance to hail class 4.
Hail resistance is also correlated with snow load capacity or mechanical resistance to frontal pressure. LG, Panasonic, SunPower, REC, Selfa and SolarWatt produce exceptional solar modules in this regard .
Of course, hail larger than that foreseen in the certificate can cause damage. So what can protect against the effects of hail?
Photovoltaic panel insurance
The best economic protection for the owners of photovoltaic micro- installations is the insurance of the photovoltaic installation , which covers the costs of repairing damaged installations. You should read the insurance conditions, because not all of them protect you from hail.
Rooftop homeowners can easily integrate the installation into a comprehensive construction insurance policy . This is the most cost effective solution.
Although solar panels should function for many years without problems, why not be fully insured? Insurance shouldn’t be expensive, especially if you’ve bought good quality panels.
Does the manufacturer’s warranty protect against the effects of hail?
Generally not. Manufacturers’ warranties do not cover damage caused by so-called force majeure . We provide an example of a warranty card note:
[Damage caused by] actions of nature or actions of God, including but not limited to lightning, hail, frost, snow, storms, waves, floods, extremely high temperatures, earthquakes, typhoons, tornadoes, volcanic eruptions, meteor strikes , cracks or landslides [not covered by warranty] – Q Cells warranty card
How to interpret this statement?
It is worth recommending all the companies in the list above.