Prospects of thin film solar cells: Towards competitive efficiencies

Photovoltaics for the supply of electricity is growing rapidly with a major market share of wafer based silicon solar cells. The yearly production of photovoltaic modules in 2011 reached worldwide 27 GW. Thin film photovoltaic modules are electronic devices with areas of square meters that are produced on a GW scale. Steady improvements of the technology and devices yield cell efficiencies 16→20%. Modules in the efficiency range of 8-13% are produced with thin films of amorphous/microcrytalline silicon, cadmiumtelluride and copper-indium diselenide materials. Even though the efficiencies of thin film solar cells still lag behind wafer based cells, there are is a significant potential for very large scale use because of the inherent advantage of thin film technologies, namely small consumption of materials and energy for module production.