Blue-sky thinking pushes up perovskite PV conversion efficiencies

A combination of perovskite solar modules positioned on top of silicon solar modules could mean that future solar power conversion efficiencies of 30% might be achieved.

This possibility follows the unveiling by Solliance, a research and design consortium, and one of its partners, nano-electronics research centre Imec, of what is claimed to be the first semi-transparent perovskite photovoltaic (PV) module that can achieve power conversion efficiencies of 12%.

The technology used creates semi-transparent PV-windows that are a primary element towards creating zero-energy buildings and research has found that when combining these semi-transparent perovskite modules with Si solar cells, 20% power conversion efficiencies are achievable.

One of the advantages of perovskite solar modules is they can be manufactured with simple fabrication techniques such as coating and printing and Imec’s stacked module design has a transparent perovskite solar module positioned on inter-digitated back-contacted silicon solar cells.

Perovskites can also be adapted to be made on flexible (plastic films or metal foils) as well as rigid (glass, metal) carriers. Optical and electrical properties of the perovskite solar cells can be varied by tuning the composition of the material components which adjusts colour and transparency.

The semi-transparent perovskite modules Imec created by scalable coating techniques showed efficiencies of 12% on sizes up to 4cm2 and conversion efficiencies of 17.2% were achieved for larger areas up to 16cm2. An Si bottom solar module of 4 interconnected inter-digitated back contact solar cells was employed.