With increasing the demand of consuming the energy to supply life’s needs, the focus of renewable energy has been increased since this energy does not have negative impacts on the environment. By applying the new technologies of solar energy, diversifying the world’s energy supply, minimizing the reliance on fossil fuel and reducing the air pollution can be made. Solar power is defined as ‘’ energy in the form of electromagnetic radiation emitted from the sun that is converted into thermal or electrical energy on the Earth’’ (UCS, 2009). The electrical current can be produced by harnessing the sun’s radiation with two different methods; one is direct conversion of sunlight into electricity using the photovoltaic (PV) system while the other is indirect conversion using the concentrating solar power system (CSP). In this paper, the focus will be on explaining the production of electricity using the photovoltaic technologies because this procedure is the most popular type. This paper begins by outlining the key aspects of photovoltaic cells, then, discovering the components of this system. The final explanation is the technical process involved in converting sunlight into electricity.
The basic construction of a PV cell is simple. According to Union of Concerned Scientists (UCS), a PV cell is usually in squared shape cell approximately ten centimeters on a side (2009). Because this cell generates a very small amount of power, which is less than two watts, PV cells are gathered jointly as one part. These grouped parts are assembled into large panels coated with anti-reflection glass or plastic in order to absorb light and to prevent the panels from the weather. These coated panels can be used as large units or arrays.
In order to understand the conversion of sunlight into electricity using PV technology, a distinction between types of the solar panels need to be understood. Union of Concerned Scientists (UCS) stated that there are generally three types of solar cells, which are made from silicon: single-crystal, polycrystalline and amorphous (2009). The single-crystal cells, which is “made in long cylinders and sliced into round or hexagonal wafers” (UCS, 2009), have efficiency as high as 25 %. Polycrystalline cells are manufactured from melt silicon formed into blocks or cut onto sheets then divided into squared shape. This type of cell has approximately 15 % efficiency for producing electricity. The third type of solar cells is amorphous silicon, which has efficiency of 5 % for producing electricity. In this type, the whole modules are made in one step. “Silicon is sprayed onto a glass or metal surface in thin films” (UCS, 2009).
According to the National Renewable Energy Laboratories (NREL), the fundamental components of PV system are: Direct current (DC) system equipments, Alternating current (AC) system equipments and other important parts of the PV system (1997).
The DC system equipments are: a PV cell, a charge controller and a...