Research into silicon-based solar cells is progressing in leaps and bounds, and the latest generation of solar cells, which will again be significantly more efficient than the currently dominant n-type solar cells, will soon be introduced: Perovskite-silicon tandem solar cells.
These cells are made up of layers of silicon and perovskite, two semiconductor materials. As the two materials are able to capture slightly diverging light spectrums, an even wider spectrum of sunlight can be converted into electricity. Perovskite-silicon tandem solar cells promise efficiencies of up to 45 percent – manufacturer Longi already achieved a record 33.9 percent in the lab.
According to a study by the German Mechanical Engineering Industry Association (VDMA), the mass production of perovskite-silicon tandem cells can be expected to start in 2027. There is still some research ongoing into how these high-efficiency cells can be launched successfully, and how they can become a scalable standard product. After all, the commercial application of a solar product and its durability are just as important as cell efficiency.
So far, research has been concentrating on the latter. Apart from technological and financial aspects, the regulatory requirements need to be right for a new solar technology to be launched successfully. At the moment, perovskite still contains a share of lead, which may put into question the economic value of tandem solar cells in the EU, due to the RoHS Directive.
The success of tandem solar cells will also depend on continued material research into how to replace rare materials such as indium, and on establishing recycling processes for environmentally harmful materials such as lead. This is necessary for the industry to meet its responsibility to provide clean power generation technology.
The market launch of perovskite-silicon solar cells is expected to hail a new age of solar technology, which is necessary to bring down the costs even further, and to considerably expand global solar power generation through high efficiency.