In research conducted under the Institut Carnot Énergies du Futur, the CEA at INES and CEA researchers in Grenoble made advances in tandem cells development and implementation on larger surfaces, achieving record yields (greater than 22%) on PV systems measuring around 10 sq. mm. The next step will be to try to maintain these high efficiencies on modules measuring 15 cm x 15 cm. Several printing and evaporation processes are being investigated and compared.
    At the same time, the first-ever tandem perovskite-on-silicon heterojunction cells were produced, with the goal of achieving yields of 30% on equivalent-sized cells (156 x 156 sq. mm; see photo opposite).