Swiss work is at the origin of important progress in solar energy. Panels made of silicon and perovskite, developed by EPFL and the Swiss Center for Electronics and Microtechnology (CSEM), have crossed the 30% yield mark for the first time.
EPFL and CSEM carried out this work in Neuchâtel, which could pave the way for more efficient electricity production. The two institutions have developed so-called “tandem” photovoltaic cells, made up of two materials: silicon and certain perovskites, a type of mineral with a certain structure.
>> More details: Perovskite, an inexpensive and promising material for solar energy
Today, silicon alone comes up against a theoretical maximum efficiency limit of around 29%. But thanks to its combination with two types of halide perovskites and the development of another cell architecture, the symbolic bar of 30% has been crossed in work carried out in Neuchâtel. Two world records have been independently certified by the National Renewable Energy Laboratory (NREL).
Abundant on the planet
Halide perovskites have been identified as an ideal complement to silicon because together they can more efficiently convert light into electricity, without unduly increasing manufacturing costs. The other main advantage of these materials is their ease of access. “The elements that compose it are abundant on the earth’s crust”, explains Quentin Jeangros, member of the research center on renewable energies at CSEM.
According to the researcher, this advance therefore opens up new perspectives. “Right now, increasing efficiency is the best way to drive down costs,” he said. Thus, showing that such “potentially cheap” devices can achieve high efficiencies could help lower the prices of more sustainable electricity.
>> Read also on the same subject: The boom in European photovoltaic production also passes through Switzerland
However, it is advisable to remain cautious, because for the time being, research is confined to laboratory experiments, on small cells. In particular, it will be necessary to ensure their lifespan in real conditions.
According to Quentin Jeangros, the costs of production will undoubtedly be higher at the beginning, “the time to set up large-scale industrial processes”. But he is optimistic about their reduction in the long term and hopes for a marketing within five to ten years.
>> See also: Despite rapid progress, the challenge of solar electricity remains colossal
Romain Bardet / jop