Solar power is one of the most promising renewable energy sources today. Solar cells, also known as photovoltaic (PV) cells, can be used as Auxiliary and Supplemental Power Sources (ASPSs). When photons in sunlight randomly impact the surface of solar cells, free electrons are generated, which flow to produce electricity. Solar cells are often assembled into flat plate systems that can be mounted on rooftops or placed at other sunny locations. A solar cell is composed of several layers of different materials. The top layer is a glass cover or other encapsulating material designed to protect the cell from weather conditions.
Beneath the glass layer is an antireflective layer that prevents the cell from reflecting sunlight away. Below this layer are two semiconductor layers that are typically made from n- and p- silicon. A set of metallic grids or electrical contacts is placed around the semiconductor material, one above the material and the other below. The energy of the absorbed light is transferred to the semiconductor. The energy knocks electrons loose from the semiconductor, allowing them to flow freely. An electric field within the solar cell forces the freed electrons to move in a certain direction. The top grid, or contact, collects the flowing electrons from the semiconductor.
The average factory price of a solar panel is about $5/watt, excluding balance-ofsystem (BOS) costs. BOS costs can result in an additional 30 to 100 percent increase to the factory costs. Major BOS cost items include control equipment (maximum power point trackers, inverters, battery charge controllers), solar array support structures, battery storage (if present), installation and associated fees, insurance, and data acquisition system and sensors. Solar Energy prices have declined on average 4% per annum over the past 15 to 20 years. In the early 1980's, system costs were more than $25/watt. Costs are expected to decrease 40% by 2010. Improvements in conversion efficiencies and manufacturing economies of scale are the underlying drivers.
For an accurate guide on how you can actually start harnessing the power of the sun by click here!