Tandem solar cell achieves 32.5% effectiveness

• The existing globe record of tandem solar cells containing a silicon bottom cell as well as a perovskite top cell has once again been broken at HZB. The new tandem solar cell converts 32.5% of the case solar radiation right into electric power.

The certifying institute European Solar Test Installation (ESTI) in Italy determined the tandem cell and formally verified this value which is likewise included in the NREL chart of solar cell modern technologies, kept by the National Renewable Energy Lab, U.S.

Scientists from HZB can dramatically improve on the effectiveness of perovskite/silicon tandem solar cells. "This is a really large jump ahead that we didn't visualize a couple of months earlier. All the teams involved at HZB, especially the PV Competence Center (PVComB) and the HySPRINT Innovation lab groups have actually interacted successfully and also with enthusiasm," claims Prof. Steve Albrecht.

Interface modifications

Albrecht's team used an advanced perovskite make-up with an extremely wise interface modification. The lead authors, postdocs Dr. Silvia Mariotti, and also Dr. Eike Köhnen in Albrecht's group, established an interface modification to reduce cost provider recombination losses as well as used in-depth evaluation to recognize the certain homes of the interface modification. These developments were after that efficiently carried out in tandem solar cells, as well as with aid of Master's trainee Lea Zimmermann, incorporated with further optical enhancements.

Furthermore, much more scientists and specialists assisted to create and fabricate the tandem cells to achieve this success. Entirely, the interface and also optical modifications enabled highest possible photovoltages (open-circuit voltage) and caused the new record effectiveness for this interesting tandem modern technology.

Fast development

Ongoing effectiveness growth by various study institutes and also firms over the last years and also particularly the last month have actually been rather amazing for the field: Various teams from HZB achieved a record value in late 2021 with an efficiency of 29.8% that was realized by periodic nanotextures. A lot more recently, in summer 2022, the Ecole Polytechnique Fédérale de Lausanne, Switzerland, initially reported a licensed tandem cell over the 30% obstacle at 31.3%, which is an amazing efficiency jump over the 2021 value.

With the new licensed value of 32.5%, the record is once more back at HZB. "We are really thrilled about the new value as it reveals that the perovskite/silicon tandem innovation is very promising for adding to a sustainable energy supply," says Albrecht.

HZB's scientific supervisor, Prof. Bernd Rech, claims, "At 32.5%, the solar cell performance of the HZB tandems is now in varieties formerly only achieved by pricey III/V semiconductors. The NREL graph clearly demonstrates how incredible the last two rises from EPFL and also HZB really are."