What are Photovoltaic Cells?
Photovoltaic cells were developed at Bell Laboratories in the early 1950s as a spinoff of transistor technology. Very thin layers of pure silicon are impregnated with tiny amounts of other elements. When exposed to sunlight, small amounts of electricity are produced. They were mainly a laboratory curiosity until the advent of spaceflight in the 1950s, when they were found to be an efficient and long-lived, although staggeringly expensive, power source for satellites. Also, the utility companies couldn’t figure out how to get their wires out into space, so PV was really the only option! Since the early ’60s, PV cells have slowly but steadily come down from prices of over $40,000 per watt to current retail prices of around $5 per watt, or in some cases as low as $3 per watt for distributors or in very large quantities.
As the world advances, new technologies arise – or, in some cases, older technologies are exhumed and improved upon. Although most people are under the impression that the field of photovoltaics is a new subject, based on recent invention, this is not actually the case. But first of all lets take a look at what “photovoltaic” means. The word “photovoltaics” can be split up in to two parts: “photo” and “voltaic”. The term “photo” is derived from the Greek word “phos” which means “light.” A “volt” is a measurement unit for electrical force. So, literally, “photovoltaic” means “electricity through light.” And that is exactly what the word means: “capturing solar energy in the form of light and converting it into electricity.” So how do we convert sunlight into solar energy and electricity? In order to convert sunlight into electricity you need to use a material called a “semiconductor”. In simple terms, a semiconductor is a material that acts as an insulator, but is also able to conduct e
Photovoltaic cells are devices that produce sunlight directly from electricity. Many photovoltaic cells put together form a solar array or solar panel. These cells convert light into electricity by harnessing the energy created when photons from sunlight knock electrons into a higher state of energy, within the cell itself. Photovoltaic cells are composed of layered materials which include two types of silicon, an anti-reflective coating, and a glass cover. The technology used to produce solar panels continues to advance, and may one day provide essentially free energy to power homes and businesses. One of the most important parts of a photovoltaic cell is the material used as the semiconductor. Silicon is the most commonly-used semiconductor, but other options are available for certain applications, which can be less expensive than silicon. When light hits the semiconductor, a portion of the light energy is absorbed, causing the release of electrons. The electric current that results
Photovoltaic cells produce electricity directly from sunlight. Photovoltaic cells are also called PV cells or solar cells. Many PV cells are used in remote locations not connected to the electric grid. Photovoltaic cells comprise the main component in solar panels and are also used to power watches, calculators, solar lights, and lighted road signs.
A photovoltaic cell is a specialized semiconductor diode that converts visible light into direct current. This electricity can then be used to power electrical equipment such as televisions, lights, stereo systems ets, just like the electricity from a power point. Photovoltaic cells come in many sizes, but most are 10 cm by 10 cm and generate about half a volt of electricity.
