LCRI’s Dr Vincent Barrioz is a member of the SPARC team based in the Centre for Solar Energy Research with Glyndŵr University. He specialises in researching innovations in thin film solar photovoltaics.
A Thin Film PV (photovoltaic) cell is made up of a substrate –for example, a sheet of glass – that is coated with very thin layers of semiconductor materials. This allows the cell to convert solar radiation into electricity. Originally used in tiny strips to power calculators, thin film photovoltaic cells are now being produced in much larger modules to harness renewable energy from the sun.
The material and manufacturing process is very important, as the cells need to be light in weight, and as efficient as possible, whilst also being cheap and relatively easy to produce. The current thin film solar PV efficiency world record stands at roughly 19%, which means that the most efficient solar PV cell, made of cadmium telluride, can convert 19% of solar radiation into electricity.
There are various processes used to coat the substrate with the photovoltaic materials, and one of them is the MOCVD (metalorganic chemical vapour deposition) method. In essence, the thin PV cells pass through a reaction zone, forming parts on an assembly line. They are coated with various chemical elements, and then pass through a contained zone filled with gases. Within this zone, chemical reactions take place and thin layers of photovoltaic material are deposited on each cell.
As part of the SPARC project, Dr Barrioz and his team have been developing an in-line system that will improve the efficiency of the PV cells, increase the speed at which the photovoltaic material is deposited on each cell, and reduce the amount of material required. This will increase the production throughput and decrease the cost of production, whilst maintaining and improving the efficiency of the cells.
Dr Barrioz said “The new chamberless MOCVD system developed by the CSER team offers great potential to develop advanced materials for thin film PV and improve their conversion efficiencies, on rigid or flexible substrates. The LCRI funded SPARC project has been a fantastic opportunity and we are confident that this is the beginning of a successful story for thin film PV manufacture in and for Wales.”
Professor Irvine said “This has been an extremely challenging and exciting project that has taken all the ingenuity of the CSER team and our industrial partner, Scanwel to design and build this in-line system. Its success is testament to their creativity and enthusiasm.”