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Overview
Photovoltaic
(or PV) systems convert sun light energy into electricity. The term
"photo" is derived from the Greek word "phos," which
means "light." "Volt" is named for Alessandro Volta
(1745-1827), a pioneer in the study of electricity. "Photo-voltaics,"
then, literally means "light-electricity."
Photovoltaic (PV) solar power is one of the most promising renewable energy sources in the world. Compared to nonrenewable sources such as coal, gas, oil, and nuclear, the advantages are clear: PV is totally non-polluting, has no moving parts to break down, and does not require much maintenance. A very important characteristic of photovoltaic power generation is that it can be installed on an individual rural school or health clinic or house, allowing specific users to generate their own power, quietly and safely. Additional solar panels can be added, as more is needed in a community, thereby allowing power generation to keep in step with growing needs. In a surprising number of cases, PV power is the cheapest form of electricity in remote areas. The use of solar energy is not new. In fact, development of solar energy dates back more than 100 years, to the middle of the industrial revolution. Over the years, photovoltaic power has become increasingly efficient and practical. How practical is solar for daily use? While appropriate only in a limited number of urban applications, in remote areas of developing countries it is highly practical and often the only option. A remote site (a school, health clinic or home) can be virtually self-sufficient with solar energy. Photovoltaic systems typically have four principal components: solar panels, (modules), an energy storage device (battery), a charge and consumption controller, and an inverter. Since solar panels produce direct current (DC) and most conventional equipment operates on alternating current (AC), the inverter is used to change the DC current to AC current. The energy is then stored for use during overcast periods and at night. It can be stored as chemical energy in batteries, or as potential energy in pumped water tanks. |
