Photovoltaics has become a more important topic due to the surge in people opting for renewable energy. It uses our most plentiful resource: the sun. In 2013, use of photovoltaic energy increased by 38% and it doesn’t appear to be slowing down anytime soon. This process is especially important to understand if you’re going to eventually install solar panels on your home or business roof.
Photovoltaics is a process that generates electrical power through converting sunlight into current electricity through the use of semiconductors. These semiconductors exhibit the photovoltaic effect, in which photons of light are converted into electrons. When these electrons are captured, the resulting current can be used as electricity (Little fun fact: The photovoltaic effect, developed by Albert Einstein in 1905, won him the Nobel prize in physics). After NASA started using the technology in 1960, the cost of designing and using the technology declined to the point where by 1970, it became more common for use outside of NASA.
The photovoltaic effect is based on the operations of called solar cells, which are made of the semiconductor material silicon. monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride and copper indium gallium selenide/sulfide Below is a diagram of a basic solar cell. As you can see, sunlight hits the semiconductor and the electricity produced turns on the light bulb. This is because the sunlight knocks electrons free from the semiconductor material, and if there is a circuit formed, those loose electrons form an electric current that is used to provide energy to the light source.
A group of solar cells inter-connected and mounted on framework is often called a solar panel or a solar module. The output is measured in volts, with a common solar panel output being 12 volts. The larger the surface of the panel, the more electricity is produced.
Photovoltaic has come extraordinarily far in the last 50 years: IKEA announced that it would sell solar modules in 17 United Kingdom IKEA stores by the end of July 2014. Currently, the world generates enough solar power to power 40 million households in the world, and solar energy represents almost 1% of world-wide electricity demand. By the year 2020, scientists predict that there will be enough solar energy produced to fulfill the energy needs of 9% of the world’s population. It’s only a matter of time before photovoltaic technology becomes cheap and efficient enough to be on every roof, in every town, in every country.