European researchers have developed a new system to increase the energy conversion of photovoltaic cells. And now the industry is ready for mass production.
The first photovoltaic cells did not exceed 10 per cent efficiency. Today the average hovers around 20 per cent, but researchers have continued over the years to work on increasing the capacity of silicon layers to convert sunlight into electricity. And this, they assure us, will be the year in which a new efficiency record will be set: 26.1 per cent. This means that solar panels could be smaller, cheaper, more efficient.
The news comes from the Institute for Solar Energy Research in Hamelin (Isfh) in Germany, where the research team led by Professor Byungsul Min set a new record thanks to "passivated" contact technology. In essence, this involves two thin layers of oxidised and crystallised silicon inserted between a solar cell and its metal contact. In this way, the risk of electric charges becoming trapped and therefore unconvertible into electricity would be reduced. "There is currently a great deal of excitement in the scientific community regarding passivated contacts," Professor Min noted at a presentation conference held in Belgium. The project, developed since 2013 by Isfh and the Fraunhofer Institute for Solar Energy Systems in Freiburg, had until now led to major advances, but had never managed to exceed 25 per cent energy conversion.
In the laboratories of the Fraunhofer Institute, work continues nonetheless to increase conversion efficiency, and researchers have succeeded in producing a wafer with an efficiency of 33 per cent — a true international record.
But for a technology to enter the market it must leave the research laboratory and be replicable. That is what happened last year: thanks to a project called Disc, across Europe research institutes and solar cell manufacturers are collaborating to optimise its design and production. The Disc consortium plans to reduce the production costs of the technology by replacing the layers of indium — which is extremely costly — with zinc, an element that has comparable physical properties to the rarer one.
A record that will allow the European industry to grow and establish itself as a leader in an increasingly competitive market.