by Carl Johannes Muth
PV panels undoubted bear al lot of advantages as they deliver emission free – clean energy. However as the technology produces on a variable basis, no sun means simply no power. Nevertheless recent developments allow PV cells to be combined with electro-catalyst for the purposes of storing the energy generated.
Artificially produced fuels such as hydrogen are most suitable for power storage especially from renewable energy. In the power-to-gas process an n-doped silicon solar cell generates hydrogen when immersed in water and illuminated with sunlight.
Unfortunately, the technology is still in the very early stages. The solar cell must be combined with several other functional layers and doing so new challenges arise. On the one hand, these layers must be transparent, so that the solar cells can generate sufficient voltage. On the other hand, the system has to be covered with a protective layer against the acidified water. Without this, the solar cell would quickly degrade so much that the process no longer works.
This problem will now be addressed by the PECSYS project as the Helmholtz-Zentrum Berlin for Materials and Energy (HZB) announced in a press release on Monday. The project is expected to develop a prototype on an area of at least ten square meters that converts more than 6% of the incident solar energy into hydrogen, while maintaining stable operation for at least six months.
According to HZB this should be achieved by testing photovoltaic cells based on different materials such as silicon and chalcogenides, as well as tandem cells based on metal halide perovskites, together with electro-catalysts and membranes to develop protective layers.
The ultimate goal of the project is to develop an integrated device that can stably operate under extreme environmental conditions and to identify a system that is most appropriate for industrial production. For this the price for generated hydrogen, current market price is around €8 per kilogram, should not exceed €5/kg.
The project runs for four years and is funded with €2.5 million by EU ’s Horizon 2020 Research and Innovation program, Hydrogen Europe and N.ERGHY. The Competence Centre Thin Film and Nanotechnology for Photovoltaics Berlin at HZB will lead the coordination, bringing together expertise from the Jülich Research Centre (Germany); Uppsala University (Sweden), the National Research Council of Italy as well as from two PV companies: Sweden's Solibro Research AB and Italy's 3SUN.
Editor's note: An earlier version of this article identified Christian Roselund as the author. This is incorrect, and Carl Johannes Muth has been identified as the correct author. We regret the error.