Berlin team at HZB develops particularly efficient record solar cell

World record for Helmholtz-Zentrum Berlin (HZB): The team has unveiled a new record solar cell that can convert 32.5 percent of incident sunlight into energy. This once again positions them at the top of the world rankings, after having to give up the spot to EPFL a few months ago.

Helmholtz Center Berlin presents new record solar cell

“The current world record of tandem solar cells consisting of a silicon bottom cell and a perovskite top cell is once again at HZB,” Helmholtz-Zentrum Berlin announces in the press release. The new record solar cell is particularly efficient and capable of converting a full 32.5 percent of incident solar radiation into energy.

The record was confirmed by the certifying institute European Solar Test Installation (ESTI) in Italy, after HZB had to cede the top spot to the École Polytechnique Fédérale de Lausanne (EPFL) just a few months ago. Now it is once again at the top of the efficiency rankings.

With the record-breaking solar cell, the Berlin team once again succeeded in significantly increasing the efficiency of perovskite/silicon tandem solar cells. A great leap forward, as Prof. Steve Albrecht confirms.

• Also interesting: Breakthrough: Transparent solar cells become more efficient

Rapid increase in energy efficiency

Yet efficiency has increased significantly, especially in recent years. It was not until the end of 2021 that teams from HZB achieved values of 29.8 percent, before EPFL was able to exceed the 30 percent mark for the first time in the summer of 2022. At the time, the team from Switzerland presented a certified tandem cell with 31.3 percent efficiency. So HZB has now surpassed this value once again by a significant margin.

“We are very pleased about the further significant leap in efficiency. This shows the high potential of the perovskite / silicon tandem solar cells to contribute in the coming years to a sustainable energy supply and the turn of the era, “ said Albrecht.

For Professor Bernd Rech, scientific director of HZB, in particular, this new record solar cell is a huge leap: “At 32.5 percent, the solar cell efficiency of the HZB tandem is now in ranges previously achieved only by expensive III/V semiconductors.”

The tandem solar cells of silicon and perovskite thereby absorb different parts of the solar radiation in different layers, which significantly increases the efficiency compared to normal solar cells.

In the process, the HZB team succeeded in significantly improving the perovskite compound in particular. When and in what form the new record-breaking solar cells will be ready for the market, however, was not disclosed.