Photovoltaic solar energy consists of the direct transformation of solar radiation into electrical energy . This type of energy is often referred to directly as photovoltaic energy.
This transformation into electrical energy is achieved by taking advantage of the properties of semiconductor materials by means of photovoltaic cells . The base material for the manufacture of photovoltaic panels is usually silicon . When light Sol ( photons ) incident on one side of the solar cell generates an electric current . This generated electricity can be used as a source of energy.
Photovoltaic Solar Energy
The manufacture of photovoltaic cells is an expensive process, both economically and in time. The silica with which photovoltaic cells are manufactured is a very abundant material on Earth. However, silicon processing is laborious and complicated. Through very complicated processes are elabroan bullion silicon . Subsequently, of these silicon ingots the wafers ( photovoltaic cells ) will be cut .
Another source of obtaining silicon is the recycling of the electronics industry.
Currently, other higher performance materials are being prepared.
It is important that all the cells that make up a photovoltaic solar panel have the same characteristics. After manufacturing the photovoltaic cells , a classification and selection process must be followed.
Photovoltaic energy efficiency
Depending on the construction, photovoltaic modules can produce electricity from a specific range of light frequencies, but in general it cannot cover the entire solar range (specifically, ultraviolet, infrared and low or diffuse light). Therefore, much of the energy from incident sunlight is not harnessed by solar panels , which could give much higher efficiencies if it is illuminated with monochromatic light.
Therefore, another design concept is to divide the light into different wavelengths and direct the beams into different cells tuned into these ranges. This has been projected to be able to raise efficiency by 50%. Scientists from Spectrolab, a subsidiary of Boeing, reported the development of multi-junction solar cells with an efficiency of over 40%, a new world record for photovoltaic solar cells. Spectrolab scientists also predict that concentration solar cells could reach efficiencies of more than 45% or even 50% in the future, with theoretical efficiencies of around 58% in cells with more than three junctions.
Currently, the best conversion rate of sunlight into photovoltaic energy in new commercial products achieves an efficiency of the solar module of around 21.5%.
Applications of photovoltaic solar energy
The main application of a photovoltaic solar energy installation is the production of electrical energy from solar radiation .
Energy production can be large-scale for general consumption or small-scale for consumption in small homes, mountain shelters or isolated sites.
Mainly there are two types of photovoltaic installations:
- Photovoltaic installations for grid connection, where the energy produced is used entirely for sale to the distribution grid.
- Isolated grid photovoltaic installations, which are used for self-consumption, whether it is an insulated house, a telecommunication repeater station, water pumping for irrigation, etc.
Within the applications of photovoltaic energy not connected to the network we find in many areas of daily life. Photovoltaic energy is used in small devices such as calculators, such as for street lighting in certain areas, to eliminate electric motors and even cars and airplanes have been developed that work exclusively using solar radiation as a source of energy.
Within the photovoltaic installations connected to the network there are photovoltaic solar power plants. A photovoltaic power plant, also a solar park, is a large power generation plant, designed for the sale of its production to the electricity grid. It is also known as a solar farm, especially if it is located in agricultural areas.
History of photovoltaic energy
The photovoltaic energy generated with the photovoltaic effect was first recognized in 1839 by the French physicist Becquerel. However, it was not until 1883 that the first solar cell was built by Charles Fritts with an efficiency of 1%. During the first half of the twentieth century there were several improvements to increase its efficiency .
In 1946, Russel Ohl patented the modern union between semiconductor materials that is currently used. But the most important technological breakthrough came in 1954 when Bell Laboratories, experimenting with semiconductors, developed the first photovoltaic cell of silicon , with a yield of 4.5%.
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