At present, along with the relatively cheap technologies for photovoltaic solar cells made of amorphous, polycrystalline and multicrystalline silicon, the RAS with Nanotechnologies developed a single-crystal geteroperehodnye tandem and cascade converters based on direct-gap compounds such as A3B5 and heterojunctions 'germanium – silicon', says ca-energy.net. Significantly improve characteristics of these solar cells and thus reduce their costs by replacing expensive can be a substrate of Ge or GAs cheaper and more technologically advanced material – a single-crystal silicon. Further development technology of solar cells on epitaxial heterostructures A3B5 compounds associated with the use of so-called cascade (or tandem) solar cells. In this case, the individual pn-transitions of the layers different chemical compositions that absorb sunlight in various lengths, connected in series with the tunnel pn-transitions, which are specially formed between the stages. New possibilities for creating high-efficiency solar cells opens the application of nanotechnology. This is the gap of the semiconductor structures, which include the so-called intermediate allowed band, which can be created, for example, when introduced into the epitaxial layer structure of quantum nanoclusters (or quantum dots). According to theoretical calculations and preliminary experiments, the conversion efficiency sunlight in the electrical energy in such a structure may exceed 60%. The volume of production increases fotoenergosistem since 2000 by about 30% per year.
It is projected that in 2020 produced the power systems of this type will be 50 GW ie for 20 years, the market volume will increase to 140 raz.Suschestvuet view that Russia – not the best country for the development of photovoltaic effect of climatic conditions. However, in southern Russia have very large areas where the average annual amount of solar energy is higher than in southern Europe. Therefore, at sufficiently low cost of solar energy, it can be a very promising source for Southern Rossii.Odin way of reducing the cost of solar power – concentrating the solar radiation. Here to reduce the cost of electricity up to 5-8 cents per kilowatt-hour can be achieved by reducing the consumption of expensive semiconductor materials. Much helps increase the efficiency of solar cells using nanostructured cascade type. Cascade solar cell is one of the most complex semiconductor devices. 20-30 layers of elements provide conversion to electricity is not only visible light but also parts of the infrared and ultraviolet spectral regions.
Modern setups provide an annual output of cascade elements with a total capacity of concentrators 10-20 MW. One of these units purchased with financial assistance from Norilsk ', there is in the AF. Joffe. At its base in the country set up a center to develop and manufacture solar cells with a cascade-type concentrators. World There are only a few such centers, in particular, two of them are in the U.S. (one of the corporation Boeing), and two – in Germany. Basically this space firms switching to the earth's energy.