The increasing demand world-wide for electricity generated from solar power has boosted research into photovoltaic cells with an ever greater degree of efficiency. One way of raising efficiency is to use PERC+ technology. Not only can its bifacial cells convert UV light into electricity on their front side, as is customary, they can also do so on their rear side. This permits the use of a reverse-sided AL finger grid system instead of full-surface contact, meaning that scattered light can also be converted into electrical power. This means that it is possible to achieve a 10% increase in the yield of solar power plants.

In the project NEXTSTEP, Plasus GmbH, CS Wismar GmbH, Institut für Solarenergieforschung GmbH, the Fraunhofer Institute for Solar Energy Systems (ISE) and Meyer Burger GmbH are focusing their research on new PERC+ cells with the aim of achieving a rise in the efficiency in industrial production of more than 23%. In the course of this project, resistance losses are to be minimised with the help of smart-wire technology, and the stability of the SiN iNanti-reflective coating on the front side of PERC+ is to be analysed and improved under UV lighting. Reducing module-manufacturing costs will also play an important role. To this end, cell processes for the production of bypass diodes will be evaluated in the module.

Parallel to this, passivating contacts based on polycrystalline-on-oxide (POLO) will be examined, as they place fewer demands on the quality of the coating layer in comparison with customary heterojunctions. This will simplify the manufacturing process.

The collaborative project NEXTSTEP is being funded by the BMWi and will run until the end of July 2020.