Conventional photovoltaic panels require very pure silicon, which is expensive, which makes the produced electricity little competitive.
The most promising alternative uses copper-indium-gallium diselenide (DSCIG), which is 350 more efficient than silicon for the absorption of incident solar energy. However, despite twenty years of research no commercial sign could be realized.
Vivian Alberts and her team (Rand Afrikaans University) have patented a process for manufacturing low-cost DSCIG panels (66 EUR for a 50 W panel with a life of 15 to 20 years). A panel of 30 m2 would produce the necessary electricity for a family of 4 people and the energy needed for its manufacture (raw energy content) would be recovered after one to two years of operation. The manufacturing process requires two instruments specially made according to the Vivian Alberts specifications: a disperser designed by Leybold Optics (Dresden) and a diffusion furnace (Wilro Technologies, The Netherlands).