Photovoltaic solar energy

Photovoltaic energy Developed in the 50 years for equipment and the first spacecraft WAS Launched Into Space in 1958. It was the only process non-nuclear power satellite energy. It Was the only process non-nuclear power satellite energy. Satellite imagery received by your TV do not come only through photovoltaics. Satellite imagery Received by your TV do not come only-through photovoltaics.
During the '70s and '80s, efforts were made to reduce costs so that photovoltaic energy is also used for terrestrial applications. DURING the '70s and '80s, efforts to Reduce Costs Were Made so That photovoltaic energy est aussi Used For terrestrial applications. The growth of the industry was dramatic. The growth of the Industry Dramatic WAS.
Since the early 80's, the amount of PV modules shipped per year (measured in MW-peak) and increased the price of modules (per watt peak) decreased gradually as the number of modules produced increased. Since the early 80's, the Amount of PV modules shipped per year (Measured in MW-peak) and the price of INcreased modules (per watt peak) Decreased gradually as the number of modules Produced INcreased. Although the price has somewhat stabilized, the amount of PV modules shipped each year continues to increase. Although the price HAS Somewhat stabilized, the Amount of PV modules shipped EACH year continued to Increase.
Some dates: Some dates: 1839: The French physicist Edmund Becquerel discovered the photovoltaic effect. 1839: French physicist Edmund Becquerel The discovered the photovoltaic effect. 1875: Werner von Siemens outlines to the Berlin Academy of Sciences a paper on the photovoltaic effect in semiconductors.  
1875: Werner von Siemens outlines to the Berlin Academy of Sciences paper on the photovoltaic effect in semiconductors. But until the Second World War, the phenomenon remains an anecdotal finding. Until the goal Second World War, the Phenomenon Remains Finding anecdotal year. 1954: Three American scientists, Chapin, Pearson and Prince, are developing a high efficiency photovoltaic cell when the nascent space industry is seeking new solutions to power its satellites. 1954: Three American Scientists, Chapin, Pearson and Prince, are Developing a high-efficiency photovoltaic cell When The nascent Space Industry IS Seeking new solutions to power satellites icts. 1958: A cell with a yield of 9% is developed. 1958: A cell with a yield of 9% is Developed. The first satellite powered by solar cells are sent into space. The first satellite powered by solar cells are felt Into Space. 1973: The first house powered by solar cells is built at the University of Delaware. 1973: The first house powered by solar cells built IS at the University of Delaware. 1983: The first car powered by photovoltaic energy travels a distance of 4000 km in Australia. 1983: The First Car Powered by photovoltaic energy travels a distance of 4000 km in Australia. 1995: Programs of grid-connected photovoltaic roofs have been launched in Japan and Germany, and became widespread since 
2001. 1995: Programs of grid-connected photovoltaic roofs Have Been Launched in Japan and Germany, and Became Widespread since 2001.





Operating Principles Operating Principles s The photovoltaic cell is composed of a semiconductor material that absorbs light energy and converts it directly into electricity. The photovoltaic cell of a semiconductor Composed IS That material absorbed light energy and Convert It Directly Into Electricity. The operating principle of this cell uses the properties of radiation and those of semiconductors. The Principle of operating this cell uses the properties of radiation and Those of semiconductors. The semiconductor The semiconductor A semiconductor is a material whose concentration of free charges is very low compared to metals. A semiconductor material Whose Is A concentration of free charges IS very low Compared to metals. For an electron bound to an atom (valence band) become free in a semiconductor and participates in the conduction current, it must provide a minimum energy for it to achieve higher energy levels (conduction band ). For year to year bound electron atom (valence band) in a semiconductor Become free and participate way in the conduction current, it must Provide a minimum energy for it to Achieve Higher energy levels (conduction band). It is the energy of the "band gap", eg, in electron volt (eV). It Is The energy of the "band gap", eg, in electron volt (eV). This threshold value is unique to each semiconductor material and ranges from 1.0 to 1.8 eV for photovoltaic applications. This threshold value is unique to EACH semiconductor material and ranges from 1.0 to 1.8 eV for photovoltaic applications. It is 1.1 eV for crystalline silicon (c-Si) and 1.7 eV for amorphous silicon (a-Si). It ITB 1.1 eV for crystalline silicon (c-Si) and 1.7 eV for amorphous silicon (a-Si).
The spectrum of solar radiation is the distribution of photons - particles of light - according to their energy (inversely proportional to the wavelength). The spectrum of solar radiation Is The distribution of photons - particles of light - According To Their energy (inversely proportional to the wavelength). The radiation entering the solar cell will be partially reflected, another part is absorbed and the rest will pass through the thickness of the cell. The radiation Entering the solar cell Will Be Partially Reflected, Absorbed Another Part IS and the Rest Will pass through the thickness of the cell.
The absorbed photons whose energy exceeds the energy of the band gap will release a negative electron, leaving a "hole" position behind him. The Absorbed energy photons Whose Exceeds the band gap energy of the Will release a negative electron, leaving a "hole" position behind HIM. To separate this pair of electric charges of opposite signs (positive and negative) and collect an electric current, it is necessary to introduce an electric field, E, on both sides of the cell. Separate to this pair of electric charges of opposite signs (positive and negative) and collect electric current year, It Is Necessary to Introduce year electric field, E, Both Sides of the cell.
The method used to create this field is that of "doping" with impurities. The method Used to create this field Is That of "doping" with impurities. Two types of doping are available: Two kinds of doping are possible: The n-type doping (negative) is to introduce in the crystal structure of the semiconductor atoms that have foreign ownership to give everyone an excess electron (negative charge), free to move in the crystal. The n-type doping (negative) Is To Introduce in the crystal structure of the semiconductor foreign ownership Atoms That Have to Give everyone a year excess electrons (negative charge), free to move in the crystal. This is the case of phosphorus (P) in silicon (Si). This is the case of phosphorus (P) in silicon (Si). In an n-type material, it greatly increases the concentration of free electrons. In year n-type material, it Greatly Increase the concentration of free electrons.
The p-type doping (positive) which uses the insertion of atoms in the crystal lattice will give a hole in surplus. The p-type doping (positive) Which uses the insertion of Atoms in the crystal lattice Will Give A hole in surplus. Boron (B) is the p-type dopant most commonly used for silicon. Boron (B) Is the p-type dopant for silicon MOST Commonly Used. When performing two different dopings (n-type and p-type) from both sides of the cell, the result after recombination of free charges (electrons and holes), a constant electric field created by the presence of positive and negative ions fixed. When performing Two different doping (n-type and p-type) from Both Sides of the cell, the result After recombination of free charges (electrons and holes), a constant electric field created by the presence of positive and negative ions fixed. The electric charges generated by absorption of radiation can contribute to the current of the photovoltaic cell. The electric charges generated by absorption of radiation Can Contribute to the current of the photovoltaic cell. When the energy of the band gap increases, the current decreases but the tension is higher. When the energy of the band gap Increase, Decrease the current goal the tension is High.





Advantages and disadvantages 
Photovoltaic technology has many advantages. Photovoltaic technology HAS Many advantages. • First, a highly reliable - it has no moving parts - making it particularly suitable for remote areas. First, High Reliability - it Has No moving parts - making it particularly Suitable for Remote Areas. This is the reason for its use on spacecraft. This is The Reason for ITS use on spacecraft. • Second, the modular nature of PV provides a simple and adaptable to a variety of energy needs. Second, the modular nature of photovoltaic panels allow easy of installation and adaptable to a Variety of Energy Needs. Systems can be sized to power applications ranging from milliWatt in megawatts. Systems Can Be sized to power applications ranging from milliWatt in megawatts. • Their operating costs are very low given the low maintenance they require no fuel or transport, or highly specialized personnel. Operating Costs are very low maintenance THEY Given the low require no fuel or transport, or Highly Specialized personnel. • Finally, this photovoltaic technology qualities ecologically because the finished product is non-polluting, silent and does not involve any disturbance of the environment, except by the use of space for large facilities . Finally, this photovoltaic technology qualities ecologically Because the finished Product is non-Polluting, silent and Does not INVOLVE Any disturbance of the environment, except by the use of space for large facilities.
Disadvantages
 
• The manufacture of photovoltaic module is the high technology investment and requires a high cost. The manufacture of photovoltaic module Is the high technology investment and Requires a high cost. • The actual yield of a conversion module is small (the theoretical limit for crystalline silicon cell is 28%). The Actual yield of a conversion module IS small (the limit for crystalline silicon Theoretical cell IS 28%). • The photovoltaic generators are competitive with diesel generators for low energy requirements in isolated areas. Photovoltaic generators are competitive with diesel generators for low energy in isolated Requirements Areas. • Finally, when the storage of electrical energy in chemical form (drums) is required, the cost of the photovoltaic generator is increased. Finally, When the storage of electrical energy in chemical form (drums) IS required, the cost of the photovoltaic generator INcreased IS. Reliability and system performance, however, remain equivalent as long as the battery and associated control components are carefully selected. Reliability and system performance, however, remain equivalent as long as the battery and associated control components are Carefully selected.