A team of researchers at the French National Solar Energy Institute (INES) at the country’s Alternative Energies and Atomic Energy Commission (CEA) has announced achieving 18% power conversion efficiency of perovskite solar modules.

They were able to achieve this level on an active surface area of 10 cm² under illumination of 1 STC sun, using a coating step carried out in air followed by a gas quenching conversion step to form the desired perovskite material. This material was developed without methyl ammonium comprising multi-cations and a mix of halogens.

Formed at low temperature <100ºC, the layer was then integrated in modules using laser ablation as a structuring process. This greatly minimizes inactive area with a fill factor of > 93% leading to the 18% efficiency level achieved.

The researchers state that the technique is compatible with integration on heterojunction silicon solar cells for tandem architecture developed within the CEA-INES.

While this efficiency level on a small surface area is still far from commercial application, the CEA-INES team said that the ‘scientific community must meet several challenges to demonstrate PSCs of large sizes compatible with industry, in order to ensure a bright future for their industrialization’.