Solar Energy

Solar power

Solar power involves using solar cells to convert sunlight into electricity, using sunlight hitting solar thermal panels to convert sunlight to heat water or air, using sunlight hitting a parabolic mirror to heat water (producing steam), or using sunlight entering windows for passive solar heating of a building. In one minute if harnessed, enough solar energy falls on the earth to provide all humanity enough energy need for a year.

Pros:
Solar power is a renewable resource. As long as the Sun exists, its energy will reach Earth.
Solar power generation releases no water or air pollution, because there is no combustion of fuels.
In sunny countries, solar power can be used in remote locations, like a wind turbine. This way, isolated places can receive electricity, when there is no way to connect to the power lines from a plant.
Solar energy can be used very efficiently for heating (solar ovens, solar water and home heaters) and daylighting.
Solar energy is free to harness.

Cons:
Solar power is not always completely predictable because it depends on the amount of sunlight that reaches the Earth at any given time. This precludes solar power generation during the night when sunlight does not reach the part of the Earth in which the cell is located and limits solar power generation when cloud cover scatters portions of the electromagnetic spectrum. To solve this deficiency solar generators can be coupled to a hydroelectric power plant through the power grid. Excess power generated by solar cells during the day can be used to pump water above the dam. The hydroelctric power plant then supplies the power at night.
Some forms of solar power are not currently cost competitive. A photovoltaic power station is expensive to build, about 10% efficient, and the energy payback time - the time necessary for producing the same amount of energy than needed for building the power device - for photovoltaic cells is between 1.8 and 3.3 years, depending primarily on location.[6]