High efficiency solar cells and developing tandem concepts

Today Solar cell technology is pushing a great effort to reach the theoretical limit of a single junction solar cells as well demonstrated by a-Si:H/c-Si (SHJ) based heterojunction solar cells able to achieve of 26.7% as performed by Kaneka’s Interdigitated Back Contacted IBC-SHJ cell. At the same time CIGS and CdTe based solar cells are increasing their record. New materials as Perovskite and Kesterite are opening a new approach to the high efficiency suggesting tandem device able to push the cell efficiency well above the single junction limit. Indeed 27% efficiency has been achieved by monolithic perovskite/silicon tandem solar cell and bifacial configuration can ensure more than 30%. Around these topics several aspects need attention for further optimization, involving TCOs, HTLs, tunnel junctions, contacts formation, texturizations and of, course, stability. In this session will be explored the aspects and technologies that constitute the base of future developing.