III-V multi-junction solar cells

Scientists in Spain have analyzed the impact of temperature and spectral conditions on III-V solar cells employed in concentrator photovoltaic modules. They claim to have assessed the cell behavior under unprecedented operating condition.

Fraunhofer ISE researchers utilized a new front metallization technique to produce a III-V gallium arsenide solar cell. For mask and plate front metallization, they used a new two-step printing scheme that reportedly allows for the realization of extremely narrow mask openings.

Chinese researchers have used metal-organic chemical vapor deposition (MOCVD) to produce a 12 cm2, five-junction solar cell with a minimal number of mismatch dislocations. The cell has an open-circuit voltage of 4.727 V, a short-circuit current density of 860 mA/m2, and a fill factor of 86.38%.

The cell, which looks externally like a device with a two-terminal architecture, was built with III-V semiconductor layers that were connected to the silicon sub-cell on the atomic level. The cell may be used in electrically powered aircraft and drones.

Finnish scientists have developed a four-junction solar cell based on III-V semiconductor materials that is said to be able to achieve a wide spectral coverage. The cell was monolithically grown on gallium arsenide by molecular beam epitaxy (MBE).

The new results mark an improvement on the institute’s previous 24.3% efficiency record. The III-V tandem solar cell is directly grown on silicon.

Swiss startup Insolight has raised €4.6 million to bring its concentrating PV module technology to commercial production. The panels have a claimed efficiency of 30% and power output of 160 W. Originally conceived for rootop solar, the product is now being recommended as an interesting option for agrivoltaic projects.