Photovoltaic solar cells generate voltage or electric current in a material when exhibited to sunlight. The electrons produced in the photovoltaic effect are transferred between varied bands within the material which results to the buildup of electricity. It was in 1839 when Alexandre-Edmond Becquerel first observed this photovoltaic effect.
Photovoltaic solar cells make up a solar panel which contains photovoltaic materials. Monocrystalline silicon, amorphous silicon, polycrystalline silicon, copper indium selenide/sulfide and cadmium telluride are the common materials used in photovoltaic solar cells.
When photovoltaic solar cells are exposed to sunlight, they create electricity that can power up an electronic equipment or recharge batteries. Spacecrafts and satellites sent to outer space are the first applications of photovoltaics. Today, photovoltaic solar cells are used to generate electricity for different uses.
Photovoltaic solar cells find its use in agriculture.
Instead of the conventional fixed-mounted systems, they are now used with innovative tracking systems that go after the sunlight’s path in order to produce more electricity. They are also being used in buildings as a primary or secondary power supply. Solar panels are either incorporated in the building’s walls and roofs. Some are mounted while some are found not on the building but on the ground near it, which is connected by cable to provide power to the building.
Photovoltaic solar cells can also be used to give power to transportation. They provide secondary sources of power to boats and cars. They are also used to power electronic devices like calculators and other devices. Currently, they are also being used to power emergency telephones, water pumps, electric meters, temporary traffic signs, remote guard posts, trash compactors and signals.
In rural places in developing countries, photovoltaic solar cells are also used to provide electricity to the community.
Solar powered LED lights are now used to replace kerosene lamps. Just recently, the solar panels are now being used to provide one-third of the power needed to light an Interstate highway interchange.
The use of solar energy has a lot of advantages. One of its advantages is among renewable energies it has the highest power density of 170 W/m2. It is pollution free when being used. Wastes and emissions are now manageable with existing pollution controls. Installation of solar panels requires little maintenance and can operate for so many years. Compared to other sources of energy, operating costs of solar panels are lower.
When fuel transport is difficult, impossible or costly, the use of solar panels to generate electricity is more economical. Ocean vessels, satellites, remote locations and island communities are direct beneficiaries of solar energy.
However, solar panels can be more expensive than other alternatives for small-scale electricity production unless you build them yourself. Solar panels require sunlight and thus they are of no use at night or on cloudy days. Because of this, there is a need for complementary or storage power system. Electricity production using solar panels is dependent on the limited power density of the insolation of the location. Because electricity from photovoltaic solar cells produces only DC power, energy loss of 4 to 12% can occur when converting DC to AC.