What is solar energy?
Solar energy, radiation from the Sun capable of producing heat, causing chemical reactions, or generating electricity. The total amount of solar energy incident on Earth is vastly in excess of the world’s current and anticipated energy requirements. If suitably harnessed, this highly diffused source has the potential to satisfy all future energy needs. In the 21st century solar energy is expected to become increasingly attractive as a renewable energy source because of its inexhaustible supply and its nonpolluting character, in stark contrast to the finite fossil fuels coal, petroleum, and natural gas.
Solar energy is commonly used for solar water heaters and house heating. The heat from solar ponds enables the production of chemicals, food, textiles, warm greenhouses, swimming pools, and livestock buildings. Cooking and providing a power source for electronic devices can also be achieved by using solar energy.
The most common devices used to collect solar energy and convert it to thermal energy are flat-plate collectors. Another method of thermal energy conversion is found in solar ponds, which are bodies of salt water designed to collect and store solar energy. Solar radiation may also be converted directly into electricity by solar cells, or photovoltaic cells, or harnessed to cook food in specially designed solar ovens, which typically concentrate sunlight from over a wide area to a central point.