THE sun is the ultimate source of all life on earth. It is also an infinitely renewable and 100% pollution free energy source. Therefore, it is not surprising that we should look to solar energy as a great potential energy source. How do we harness energy from the sun?
One way is through the use of solar panels.
Solar panels convert the sun’s energy directly into electricity. The basic unit of a solar panel is a solar cell, which usually consists of one or two layers of silicon-based semiconductor wafers. When struck by the photons in sunlight, the solar cell generates an electrical charge due to the “photovoltaic effect” – which is a pretty good name, since it produces voltage from photons. [ihc-hide-content ihc_mb_type=”show” ihc_mb_who=”2,3,5″ ihc_mb_template=”1″ ]
The flow of these electrons moves in a steady electrical current from one side of the cell to the other. Dozens of these PV cells are packaged together into solar modules, which in turn are packaged into solar panels that are mounted on a rooftop and arranged to
maximise their hours of exposure to direct sunlight. Because the electricity generated by all those solar cells is direct current (DC), it is then sent to an inverter that transforms the power into the same alternating current (AC) used by the appliances in your home and
the local utility electricity distribution grid.
Bell Laboratories’ scientists Gerald Pearson, Calvin Fuller and Daryl Chapin designed the first practical photovoltaic cell in the mid-’1950s in New York. The successful first trial of their solar panel, made up of razor blade-sized strips of silicon, was first used on Oct 4,
1955, at a telephone carrier in Georgia. Bell Labs went on to supply solar electric power for NASA’s first permanent satellite in 1958.[/ihc-hide-content]
