All rooftop solar panels look pretty much the same from the outside: same size, same thickness and even the same installation system. But on the inside, the solar panels developed by EPFL spin-off Insolight stand apart. They deliver yields of 29% – nearly twice as much as the others currently on the market (which have yields of 17–19% ). Insolight’s panels, which were recently tested by an independent lab, use a patented optical system that concentrates sunlight on a kind of miniature photovoltaic cell normally used in satellites
Boosting efficiency while keeping a lid on costs
Studies have shown that the average yield on commercial solar panels has increased by just 3.5 percentage points since the 2000s and seemed to be reaching a plateau. But Insolight’s three founders – Mathieu Ackermann, Laurent Coulot and Florian Gerlich – wanted to push yields further and decided to try something radically different: build residential solar panels that employ the same kinds of cells used in satellites, which are very efficient but also very expensive. To keep costs down for the retail market, they developed a protective glass on which optical lenses can be placed that concentrate sunlight by some 100x and direct it to the tiny surface of the high-performance cells. That means the cells need to take up less than 0.5% of the solar panel surface. The founders also designed a mechanism that can move the cells horizontally by a few millimeters each way in order to follow sunlight throughout the day.
Read more at Ecole polytechnique fédérale de Lausanne (EPFL)
Image Credit: Cécilia Carron / EPFL