Photovoltaics Technology: Brief Description and Background

Brief description and background
According to the U.S. Department of Energy (2011), the photovoltaics is a method to generate electricity directly from solar radiation or sunlight, additionally, the another name of which is usually known as solar cells. The term ‘photovoltaic’ consists of two words, which are photo, the Greek word referring to light, and volt which is related to Alessandro Volta, the electricity pioneer. Boyle (1996: p.92-93) stated that the first discovery of the photovoltaic effect was conducted by Edmond Becquerel, a French physicist, in 1839. He found that when the silver plates of the battery were exposed to light, they enhanced the overall voltage. Nevertheless, the first paper about such finding was introduced in 1877 by Adams and Day, the two Cambridge scientists who described the observation on electrical properties of selenium, a non-metallic element, when faced to light. In the 1880s, the first selenium solar cell, which was similar to the today’s silicon solar cells, was made by Charles Edgar Fritts, an American electrician. However, the efficiency of selenium solar cell was less than 1%. It was not until the 1950s that the first silicon solar cell was made accidentally by Darryl Chapin, Gerald Pearson and Calvin Fuller while they were researching on the silicon semiconductors at the Bell Telephone Laboratories in the U.S. Referring to the Florida Solar Energy Center (2007), in the 1980s, the photovoltaic technology was widely used for powering electronic equipment; such as watches, calculators and small battery-charging applications. Furthermore, Boinpally (2010) claimed that, in 1985, the researchers at the University of South Wales could increase the efficiency of the silicon solar cells up to 20%. Then, in 1999, the total installed photovoltaic capacity reached 1000 megawatts worldwide. According to the National Renewable Energy