The myth: “The panels explode before the tiles”
The dramatic images of the storms of July 2023 at the level of the Jura arc betray a false impression. VKF investigators observed, roof after roof: the terracotta tiles were shattered, while the "glass-glass" solar modules (bifacial encapsulated between two layers of 2 mm tempered glass) had paradoxically formed a shield and survived. Investing in a good “Glass/Glass” panel is not just a matter of long-term performance, it is pure mechanical resilience in the face of super-cellular storms that have become frequent on the Swiss Plateau.
The Regulatory Checklist for Building Insurance
In Switzerland, cantonal establishments (ECA/ECAB) hold a monopoly on fire and natural elements, which is very protective, but requires formality. As soon as the installation has been installed and the ESTI certificate has been issued, write to request an increase in the “new insurance value”. The premium will often only increase by CHF 20 to 50 per year. Above all: send your advisor the data sheet mentioning the HW accreditation of the panel, appearing in the index of recognized Swiss materials (Hagelregister).
Bifacial Glass/Glass (Glass-Glass) VS Glass/Film (Glass-Foil)
This is where you should not spend too much on the franc to please an attractive quote. Conventional panels (often the ultra-low cost, “Glass-Foil” brands) have only a sheet of polymer on the back and a single glass on the front. Their structural properties on impact bend the surface. So-called “Glas-Glas” or Dual-Glass modules (like our Solyco or Meyer Burger references) act like a rigid car windshield. At 7 Swiss franc cents per Watt the price differential: this is your best franchise.
Hidden damage (The role of the Microinverter)
What we don't know: hailstones that don't break the glass field often hide an internal "Snail Trail". Micro-fracture = thermal loss 2 years after the event. Without the exhaustive collection of data via Micro-inverter (Enphase), the loss of yield will not be attributable to the storm at the time of the globalized annual assessment of a Central Inverter (String inverter), and the ECA will not take it retroactively five years later. A word to the wise, for the most exposed roofs.