On 24 September 2018 at the EU-PVSEC conference, a consortium of four leading energy research institutions presented a thin-film tandem solar cell achieving a record efficiency of 24.6 percent. The tandem cell consists of a top perovskite cell developed by imec, EnergyVille and Solliance, and a bottom CIGS cell from the Centre for Solar Energy and Hydrogen Research (ZSW, Stuttgart, Germany).
The perovskite top cell in the tandem uses light in the visible part of the solar spectrum, while the light in the near-IR spectrum that passes through the perovskite cell is harvested by the underlying CIGS cell. In this way, the tandem cell significantly outperforms the stand-alone perovskite and CIGS cells. Moreover, both perovskite and CIGS cells are thin-film solar cells, paving the way to high efficiency flexible solar cells and building integrated photovoltaic (BIPV) solutions.