In general, crystalline bifacial glass-glass modules with a high level of efficiency are used. Bifacial modules are characterised by the fact that both sides have a glass surface, so can both generate electricity.
At the moment, bifacial n-type glass-glass modules with an output of approximately 400 watts and efficiency of around 20% are generally used. For the vertical bifacial concept from Next2Sun GmbH, as well as front side efficiency, bifaciality (back side efficiency) is key. Here, the n-type glass-glass modules used with a back side efficiency of more than 90% offer a very good level. The upcoming technological change to heterojunction cells is likely to bring further improvements in terms of module efficiency and bifaciality.