Discovery of solar technology
The idea to use sunlight as an energy source is not so new. In 1839 for the first time this effect has been discovered by Alexandre Edmond Becquerel. He found in some experiments with electrolytic cells that current flows are minimally greater in light than in the dark. However, it should still take a long time before this discovery could be used practically.
1883, the first precursor of today’s solar cells was developed, was built by Charles Fritts. 1921 succeeded Albert Einstein, the theoretical explanation of this effect, for which he was awarded the Nobel Prize for Physics. Two years later, the effect could also be confirmed in an experiment, and for that he also received a Nobel Prize.
Solar technology is constantly evolving since then and always finds new applications. The first systems were equipped with solar cells, were American satellites in the fifties, and now there are solar cells in the areas of daily life. Since the seventies in most calculators it was used, either as a sole source of energy or as a combination with a normal battery. In addition, the solar technology is used for several years for the independent illumination of objects or buildings, or as an energy source for parking meters and street lights. Especially in the last ten years it is especially in Germany are increasingly used also to produce electricity and hot water. All these methods, however, are based on the same technology.
If you could use the entire energy of annual solar radiation on the earth for the production of electricity, you would be able to meet the 15,000-times the annual energy needs of mankind. This use, however, is virtually impossible, but the figures show clearly how much energy the sun can provide. The light from the sun hits at different wavelengths on the earth. The range goes from the extremely short wavelength UV light over the range of visible light to the infrared light at very long wavelengths. A portion of this light can be used for energy without producing CO2 or other harmful gases. This occurs in the solar cells, which are used to generate electricity. These cells are usually connected together in larger units, the so-called solar modules. They produce only direct current, which cannot be fed into the normal power supply. Before that the direct current is converted by an inverter into alternating current so that the feed is easily possible.