The Inner Workings Of Solar Panels

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How Do Solar Panels Work?

Solar panels are now a well-known source of renewable energy. The power generated from the panels can be used to heat water which can be used throughout the household instead of having to buy electricity from the grid. The majority of grid power is produced in a non-renewable process. The theory is that the panels are able to convert the light energy from the sun, an almost infinitely lasting power source, into electrical energy which can be stored and used as a replacement to oil or nuclear generated energy. That is a very simple explanation for a very complex natural phenomenon.

What Are Solar Panels Made of?

Silicon is an important part of the solar panel. The most simplistic part of a solar panel is a solar cell which is made of two layers of silicon semiconductor wafers. These semiconductor wafers are able to generate electrical charge after they come into contact with photons, which are a part of sunlight. The generation of electricity through this process is known as a photovoltaic effect. A photovoltaic effect is the conversion of light to electrical current via the use of a material from the exposure of light. The exposure of the sunlight onto the surface causes the electrons in the valence band, a band that is close to the Fermi level which is the total chemical potential required for electrons, to become excited after absorbing energy and jump to the conduction band becoming free. Ionisation of crystalized atoms in the material surface causes a chemical imbalance which drives the electrons. Some of the non-thermal, highly excited electrons diffuse and reach a junction where they accelerate through a built-in potential generating an electromotive force generating electricity. The percentage of electrons that are excited and diffuse reach the junction is proportional to the efficiency of the conversion of light into electrical energy.  SolarTech, who cater for both business and homeowners, use the following diagram to detail the photovoltaic effect.

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There are multiple PV cells arranged together to form a photovoltaic system. The cells are wired in series and are protected by a tempered glass which is a soft, flexible sealant that protects from the weather. The electrical connections are in series to achieve the required output voltage and/or parallel if there is a required current capability. Conducting wires are made of components of silver, copper, or any other nonmagnetic conductive material to take the current from the modules.

The frequency of light is important in determining the efficiency of the panels. The majority of the light spectrum can be converted with the exception of ultraviolet, infrared and other low or diffused frequencies of light this means that the majority of incident sunlight is not able to be converted. However, monochromatic light which is visible light of narrow wavelengths provides higher efficiencies. The efficiency of solar panels has increased through the innovation of the technology. A significant increase in efficiency was achieved by splitting the light into different wavelength ranges and then reflecting it onto the respective cells designed to carry out the photovoltaic process for that width of light.