Solar power

Solar power is the generation of electricity from sunlight. This can be direct as with photovoltaics (PV), or indirect as with concentrating solar power (CSP), where the sun's energy is focused to boil water which is then used to provide power.

Solar power provided 0.02% of the total world energy consumption in 2008. The largest solar power plants, like the 354 MW SEGS, are concentrating solar thermal plants, but recently multi-megawatt photovoltaic plants have been built. Completed in 2008, the 46 MW Moura photovoltaic power station in Portugal and the 40 MW Waldpolenz Solar Park in Germany appear to be characteristic of the trend toward larger photovoltaic power stations. Larger ones are proposed, such as
the 100 MW Fort Peck Solar Farm, the 550 MW Topaz Solar Farm, and the 600 MW Rancho Cielo Solar Farm.

Terrestrial solar power is a predictably intermittent energy source, meaning that whilst solar power is not available at all times, we can predict with a very good degree of accuracy when it will and will not be available. Some technologies, such as solar thermal concentrators have an element of thermal storage, such as molten salts. These store spare solar energy in the form of heat which can be made available overnight or during periods that solar power is not available to produce electricity. Orbital solar power collection (as in solar power satellites) avoids this intermittent issue, but requires satellite launching and beaming of the collected power to receiving antennas on Earth. The increased intensity of sunlight above the atmosphere also increases