PERC solar cells made of 100% recycled silicon have a conversion efficiency of 19.7%

Waste is reborn! German scientists made regenerative PERC solar cells from 100% waste modules, with a conversion efficiency of 19.7%.

Global carbon reduction and green energy have become obvious. The amount of solar energy equipment is increasing year by year. In 2020, the global solar energy equipment amount has exceeded 700GW. However, solar panels have their lifespan, and they will be damaged due to natural disasters and other accidents during use. , it is necessary to replace the old or replace the new module, so it is necessary to start thinking about the future of the solar panel now, otherwise the abandoned solar panel will become a waste that makes all countries troublesome.

In Germany, about 10,000 tons of discarded solar panels enter the recycling field every year, and the number will surge to hundreds of thousands of tons in 2029. For this reason, the Fraunhofer Center for Silicon Photovoltaics, a German applied scientific research institution, Fraunhofer Solar The research center (Fraunhofer ISE) and the German solar energy recycling company Reiling GmbH & Co. KG are working together to develop a technology that "any type" of solar panels can be recycled and reused, so that the abandoned modules can get a second spring.

Fraunhofer pointed out that the team first separated 0.1-1mm battery fragments from glass and plastic through various sorting processes, and then used wet chemical etching technology to remove backside contacts, silver contacts and resistance step by step. The reflective coating, and finally the emitter.

The German team will eventually also recycle silicon into PERC cells, with a conversion efficiency of 19.7%. Although it is lower than the 22.2% efficiency of today's PERC solar cells, the power generation is definitely higher than that of waste solar cells.

Usually wet chemical etching technology is mainly used in the processing of single crystal and quasi-single crystal, and finally silicon chips can be made. German scientists said that the new battery is completely made of recycled silicon, and no commercial pure silicon is added during the manufacturing process. The mystery is inconvenient to disclose, Fraunhofer CSP project manager Peter Dold admitted frankly that there is no way to explain the technical details in detail.