The Timeline: Solar power

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1860: Sun-powered steam

Auguste Mouchout was the first to patent a system which turned the sun's energy into steam, which he used to drive a steam-powered engine. The availability of coal meant that the French monarch, Napoleon III, who had up to this point financed his experiments, decided to use coal instead of solar energy for transport.

1958: The solar satellite

Vanguard 1 was the first solar-powered satellite launched into orbit. It was powered by six solar cells which allowed it to continue communicating with Earth long after its chemical battery had run out. Although communication with it was lost in 1964, it remains the oldest man-made satellite currently in orbit.

1973: An oil alternative?

Despite the emergence of solar energy in the late 19th century, the rate of development quickly dropped off in the early stages of the 20th century. The increasing availability of coal and oil meant that the demand for alternatives quickly dried up. The 1973 oil embargo put in place by Oapec (Organisation of Arab Petroleum Exporting Countries) on the US for its support of Israel in the Yom Kippur War meant that Western nations quickly began exploring the alternatives to imported fossil fuels. But rather than solar power, nuclear and coal power remained at the fore.

1982: Enter the Mojave sun

As the limitations of fossil fuels dawned on scientists, governments and the population as a whole, massive investment in solar power began. In 1982, the first photovoltaic megawatt-scale power station went on-line in Hesperia in the Mojave Desert in southern California. Solar One was operational only for a few years but was followed by dozens of others around the world, primarily in the United States and Spain. The Mojave remains the home of the world's biggest solar generators.

2011: Google signs up to solar

Google has recently invested $170m into the world's largest solar-powered tower plant – also in the Mojave. This plant will focus the sun's energy on to one 450ft-high central tower, which will use the energy to heat water to produce steam at high pressure in order to drive turbines and produce electricity. Work began on the site in October 2010 and it is a major investment by Google into clean energy alternatives. Once completed, the site is expected to produce 392MW of energy, enough for 140,000 homes at peak times.