PHOTOVOLTAIC FOR SOLAR ENERGYPhotovoltaics (PV) or solar cells as they are often referred to, are semiconductor devices that convert sunlight into direct current (DC)
electricity. Groups of PV cells are electrically configured into module and arrays, which can be used to charge batteries, operate motors, and to power
any number of electrical loads. With the appropriate power conversion equipment, PV systems can produce alternating current (AC) compatible with any conventional appliances,
and operate in parallel with and interconnected to the utility grid.
History of Photovoltaics
The first conventional photovoltaic cells were produced in the late 1950s, and throughout the 1960s were principally used to provide electrical power for
earth-orbiting satellites. In the 1970s, improvements in manufacturing, performance and quality of PV modules helped to reduce costs and opened up a number of opportunities for powering remote terrestrial applications, including battery charging for navigational aids, signals, telecommunications equipment and other critical, low power needs.
In the 1980s, photovoltaics became a popular power source for consumer electronic devices, ncluding calculators, watches, radios, lanterns and other small battery charging
applications. Following the energy crises of the 1970s, significant efforts also began to develop PV power systems for residential and commercial uses both for
stand-alone, remote power as well as for utility-connected applications. During the same period, international applications for PV systems to power
rural health clinics, refrigeration, water pumping, telecommunications, and off-grid households increased dramatically, and remain a major portion
of the present world market for PV products. Today, the industry’s production of PV modules is growing at approximately 25 percent annually, and major programs
in the U.S., Japan and Europe are rapidly accelerating the implementation of PVsystems on buildings and interconnection to utility networks.
