Hailstorms are becoming more and more common in Germany. But what does that mean for your photovoltaic system? In this article, you will find out whether hail poses a risk to solar modules, what damage can occur and how you can protect yourself against it.
First things first
- Hail only rarely causes damage to photovoltaics;
- Possible damages include microcracks or cell breaks, frame and glass damage;
- Hail damage is usually covered by home contents insurance.
How vulnerable is photovoltaics to hail?
A photovoltaic system can withstand normal hailstorms. Damage to PV modules caused by hail is rare. Damage can only occur if the hailstones are over 5 cm in diameter.
What damage can hail cause?
In extreme weather conditions with hail, microcracks can appear in the solar cells, the solar glass can break or the frames can be damaged.
- microcracks or cell breaks are tiny, but can weaken the durability of the module,
- glass damage are visible and can be large-scale, leading to the failure of the entire system,
- damage to the frame may not be immediately visible, but can lead to insulation failures.
All of these damages directly lead to a loss of performance and/or a shortening of the service life of the PV modules.
Solar modules are rarely damaged by hail here (JRP Studio – stock.adobe.com)
How great are the performance losses caused by defective PV modules?
A report by TÜV Rheinland on photovoltaic systems found that only 10% of the time did a drop in performance occur due to lightning, thunderstorms and hail. This corresponds to a loss of performance of less than 11%.
Which emergency measures should I hailstorm initiate?
After a hailstorm, check all solar modules for visible damage. If you notice any damage, switch off the PV system and contact your PV installer.
How can I protect the PV modules against hail damage?
All modules on the market undergo a safety test by TÜV. This includes snow load, fire, corrosion and hail tests. The IEC 61215 certificate indicates whether a PV module is hail resistant. Class 2 modules have passed the normal TÜV test. Class 3 modules pass a more stringent hail impact test.
Hailstone tests with 25 mm grains are common. The modules are shot at with steel balls that move at around 80 km/h. For class 3, solar collectors and photovoltaic modules are subjected to a more stringent hailstone test. Here, the hailstones are 35 mm in size and reach a speed of almost 100 km/h.
Information about the hail test can be found in most manufacturers’ data sheets.
Can hail damage to PV modules be repaired?
Repairing a PV module is unusual. If it is damaged, it is usually replaced. PV systems are considered part of the building, so home contents insurance covers the costs.
Defective modules can cause failures and short circuits in wet weather, causing the inverter to automatically shut down the system. If the sun dries the module and the hailstorm has not damaged the cell connectors, it can start up again without any loss of performance. Bridging the module is another option to maintain production of the module string and reduce time pressure for repairs.
Which insurance policies offer protection against hail damage to photovoltaic systems?
If the photovoltaic system is attached to the house, it is covered by the home contents insurance. However, you must inform your insurer about the PV system. In new policies, it is usually already taken into account. In old contracts, it is added later. The PV system increases the value of the property and thus the insurance premium.
Does the manufacturer's warranty protect against the effects of hail?
The manufacturer's warranty does not usually cover damage caused by force majeure such as hail. The product warranty guarantees the quality and freedom from defects of the product. It only covers material and design defects as well as defects in workmanship.
