Solar battery

Solar cell - a transmitter of radiant energy into electrical energy using a variety of effects.

Prerequisites for solar panels

In the period from 1965 to 1985 solar capacity increased by units of watts to hundreds of kilowatts. Simultaneously to 20% increased efficiency. But the main thing - became finally reduces the cost! It was found that in areas north of 45 degrees latitude is not always appropriate to apply, for example, solar collectors for hot water, but the battery consistently provide positive economic Effect. When the total annual solar flux of 1200 kWh / sq. m succeeds:

• provide heating needs to 25%;
• receive hot water - up to 50%;
• provide a climate control system by 75%.

Such a goal requires a responsible approach. Today, Europe switches to the battery, for fear that the Gulf Stream carries warm water to the shores of Great Britain from the equator, gone... Allegedly ripple currents caused by some factors governing the onset glacial period led to flow change.

Scientists believe that the incidents associated with the oil in the Gulf of Mexico more manifest with regard to global climate change. Today, the Old World countries willing to support everything that is connected with batteries and wind power. Created programs that allow local people... to pump electricity into the network in a natural way.

The proportion of power consumption reduces environmental pollution products of combustion of liquid fuels. In Europe, most governments buys energy, like a battery holder allows you to cut to zero waste, in addition - to earn. It is estimated that the average family spends 3,000 kWh per year. To meet the demand on foggy Albion will need 12 panels of 280 watts. In sum, the price is $ 12,000. In Russia, after the situation with Crimea it does not look cheap, but for the average European family is acceptable.

The history of the development of solar energy techniques

Rumor has it that in the VII century BC, used a magnifying glass to burn ants and a fire. In ancient Rome and Greece sent concentrate the sun's rays to ignite torches in churches. Light used for military purposes. In 212 BC. e. in the defense of Syracuse Archimedes tried to set fire to the Roman fleet, reflecting the rays of bronze shields. Although success has not been achieved, and later, in 1973, the naval forces of Greece were able to destroy the boat in the same way from a distance of 50 meters.

In Byzantium, it was so popular during the day brightly lit room that the Code of Justinian, interpreted the concept of the right of the sun. In 1767, Swiss scientist Horace Benedict de Saussure was the first to use light energy for cooking food. The device is called the stove reminded reflector satellite dish. Appropriateness of the title, in the light of culinary topics. Later Sir John Herschel used a similar expedition to North Africa.

Photovoltaic effect discovered by Edmond Bakkerelem in 1839. In the study of platinum and gold plates immersed in a medium with varying acidity he found the formation of the electric potential. William Grylls Adams and Richard Evans Day discovered that between platinum and selenium, a pair capable of exhibiting the photovoltaic effect. First celebrated exclusively in liquid media. It is a proven fact that the solids are able to produce electricity without mechanical movement at the expense of the only solar energy. The total effect turned out, however, is too low for commercial application in batteries.

In 1880, thanks to Samuel Langley was born first bolometer to assess the capacity of the glow of the heavenly bodies. By potential difference value determined by the target value. They used an ordinary LDR, but such studies are gradually laid the basic elements to create the future of solar panels. Three years later, Charles Fritz created the first swatches based on selenium wafers.

Gradually science comprehended the structure of the solar spectrum. It has been found that the invisible rays exert a strong influence on the materials. For example, ultraviolet induced in a spark discharge gap at a low voltage between the metal electrodes. In many ways science was the creation of the solar panels. While Albert Einstein explained photoelectric effect (in 1921 he was awarded the Nobel Prize), Polish scientist Jan Czochralski silicon single crystal was able to grow. Contemporaries saw no connection, but today we see how the two phenomena are used in solar cells.

Finally, in 1932, the photovoltaic effect demonstrated on the basis of cadmium sulfide, telluride is used more often today. By 1953, it outlined the theoretical basis for the calculation of the efficiency of materials for use in the battery. Born technology: Bell Labs Calvin Fuller and Gerald Pearson created the first cell on silicon sheets. Initially, the solar cell efficiency was 4%, later raised to 11%, and in modern models reaches 21. This is the worthy competition incandescent light bulb with a difference that the sun's rays while free.

In the west, the price is such that the unit cost of kWh battery is able to compete with the fossil fuel resources of the planet. The technology is patented and has its first business center with heated water with solar energy in the United States. As is known, in 1958, went into orbit the first satellite powered in part by silicon cells. The subsequent course of events is clear: design became cheaper, becoming smaller and more efficient. In 1981 McCready made the first airplane, powered solar energy.

In 1999, Times Square has its first skyscraper, where southern and western facades of floors 37 to 43 cells were silicone sheets.

How solar panels work

Inside there is a film of silicon surrounded on all sides by a layer of transparent material. The physical meaning of the photovoltaic effect: photon energy knocks electrons from their homes to the conduction band, the formation of free charge carriers. To bring them in motion used Galvani potential generated at the contact of two dissimilar materials. Phase is solid and the liquid.

In the quiescent state, without radiation of the sun, due Galvani potential at the interface formed by a double layer of charges, known from the descriptions of the processes occurring in the p-n-junction. Then the system comes into equilibrium, and nothing happens. In result, the medium is transformed into an insulator, all charges are occupied.

When the sun's rays fall on the surface - it trying to make possible an extensive - form the bulk of the unemployed electrons. They are addicted to the field, creating a movement, begin to recombine at the border. The process continues until Wednesday is still ongoing until the photon energy helps to release electrons in the solar battery.

It looks strange, if materials with a difference Galvani discovered ultra-low resistance, to generate electricity without the help of the sun. In nature, the effect is unknown, but it is impossible to artificially create theorists - interfere with practice. So, the price of the generated electricity is solar photons. Since the device works.

Voltage depends on the area of ​​the photovoltaic cell, the current is dialed due to a consistent inclusion. In modern units recruited 48 - 72 pieces. As a result, at a voltage of 25 - 40 V are given 150 - 300 watts each. Special materials are used in construction. Gradually, the course of history to discover new. For example, since 1873 known photoconductive selenium.

To effectively use the energy necessary to transform it into a digestible form. A device as solar battery in the composition comprises an inverter engaged in alternating current transformation, providing the consumer. In addition, part of the solar energy stored in the battery. As a rule, the only inverter to a plurality of cells. Modern embodiments efficiency reaches 97%, with accrued smart options type maximum use efficiency of photovoltaic elements.

Features Solar

Any such battery has a relatively peak power generated at a flux density of 1000 watts per square meter. Equivalent solntsepoku in the tropics. A system with a peak power of 1 kW by area occupies 5 - 14 square meter, depending on the material type and other factors.

The main characteristic is the price of solar panels. In Russia, set in 3000 kWh will rise in the amount within a million rubles.

solar cell efficiency is not too high, but clever brains are already thinking in that direction. It is found that for a material exhibiting photovoltaic properties characteristic optimal region of the spectrum. We have already made proposals to break up the rays with the help of filters and components of each guide track. Thus, at times be able to increase efficiency. Already in development are systems where the parameter is over a 40%. It is understood that included and engineering costs in the price of the batteries.

Whether to buy a solar panel

In 2000, Morrison's family a total of eight people from the State of Colorado (USA) established in the house the largest at the time of the reported battery. Her power was 12 kW. History is silent as the owner had to pay for such a delicacy, but even today the equipment is worth a fortune. For example, 40 thousand. dollars.

Russians until about free energy does not need to worry. We believe that the end space technologies will be on the roof of the house each.