Solar energy has been used by humans for 2,700 years. Originally, glass lenses were used to make fire with the sun's rays. According to the U.S. Energy Information Administration, the first recorded use of a solar thermal collector box was by British astronomer John Herschel in the 1830s. On a trip to Africa, Herschel used the box to cook food. In 2014, human beings use solar energy in many ways.
E-school Today explains that there are two basic ways to produce electricity from sunlight. Photovoltaic or solar cells use semi-conductor materials to produce electricity directly from sunlight, however solar panels do not. For instance, solar thermal power plants use large solar panels to concentrate solar energy to heat up water to turn electric turbines. Twelve such solar thermal plants exist in the United States, 11 in California and one in Nevada.
Renewable Resources states that the largest solar array in the world covers 1,000 acres in the Mojave Desert in California. The array uses troughs to direct sunlight towards a pipe in front of the solar collector. Because of the parabolic shape of the mirrors, the sunlight gets up to 100 times hotter than normal to heat the pipes to 750 F. The largest photovoltaic plant in the world is Golud Solar Park in China.
Alliant Energy Kids explains that more than 10,000 homes in the United States run completely on solar power. Solar power is virtually limitless because enough sunlight falls to the surface of the Earth in one hour to cover the energy needs of humanity for one entire year.