Solar Cloth System

Good atmosphere, and comfort to boot

Alain Janet, a man besotted with the sea, took inspiration from boat sails to develop a light and flexible solar cell fabric. It is used on aerostats, greenhouses and yachts competing in the Vendée Globe.

by Eve Chatelet

Solar energy doesn’t have to mean those bulky, heavy panels you see on house roofs. Solar Cloth Systems, a Mandelieu-based company founded by Alain Janet, shows the way forward. “When we graduated from Sciences Po, some people went off to raise goats on the Larzac plateau, but I had taken to the sea like a religion,” says the businessman with a smile. So, diploma in hand, Alain Janet became a sail-maker and boat-builder. The boat market was hard hit by the subprime crisis, so he broadened his scope. “At that time, boat owners were putting their boats up for sale: nobody knew how long the crisis would last. You could also see that mindsets were changing, with younger people preferring more individual, less costly seaside sports like kitesurfing and foiling. But at that moment a client, just back from a regatta, suggested I put a layer of solar cells in my sails. I was already making top-grade racing sails with multi-layer encapsulation. We had the know-how, but it was several years before we managed to embed semiconductors in our sailcloth.” Solar Cloth was born in 2014.

A flexible, shatterproof, rollable fabric

Bringing together textile and photovoltaics know-how, the company fine-tuned a technology using a hundred times less materials than rooftop panels and weighing ten times less. “The journalists were the first in the sailing community to be impressed by our sails, because in those days leisure sailors were not much concerned about environmental issues. Then in 2016, we equipped a yacht which completed the Vendée Globe race (non-stop round the world via the three capes). And as our fabrics proved capable of resisting very strong UV rays and very high temperatures, the Centre National d’Etudes Spatiales certified us to equip stratospheric balloons,” says Alain Janet. Supported at the start by the PACA Region and BPI France and then by ADEME, the start-up managed to raise enough funds to adopt CIGS solar cells – made from Copper, Indium, Gallium and Selenium. “With these four elements, which are not rare earths, we get a yield close to that of silicon solar cells. We are now working B to B to equip planes, cars, trucks, boats, and buildings where classic solar panels aren’t possible. We are proud to say that our little French firm is now a partner of the German institute Fraunhofer-Gesellschaft, a European leader in applied science, and we will soon be equipping a structure at the entrance to the 2024 Olympic Games athletes’ village, for EDF.”