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Brief History of Solar
Solar cells of practical use have been available since the mid 1950’s when AT&T labs first developed silicon solar cells with efficiencies of 6%. By 1960 Hoffman Electronics's Semiconductor Division increased commercial solar cell efficiencies to as much as 14%. The commercially available solar cells today are about 18% efficient. That means that out of the total energy that hits the surface of a solar cell, about 18% is converted into usable electricity.
The history solar power dates back as far as the 19th Century when in 1839 the French physicist Edmond Becquerel first showed a photovoltaic effect. PV is the abbreviation for photovoltaic. The word Photovoltaic is formed from photo- which means light and voltaic which means electrical current or electricity. Edmond had found that certain materials would produce electricity when exposed to light. 66 years later, in 1905, we gained an understanding of Edmonds' work when the famous physicist Albert Einstein clearly described the photoelectric effect, the principle on which photovoltaics are based. In 1921 Einstein received the Nobel Prize for this work.
The first long-term practical application of PV cells was in satellite systems. In 1958 the Vanguard I, was launched into space. It was the first orbiting vehicle to be powered by solar energy. Photovoltaic silicon solar cells provided the electrical power to the satellite until 1964 when the system was shut down. The solar power system was so successful that PV’s have been a part of the space program ever since. The sun provides endless nonpolluting energy to the satellite power systems.
The energy crisis and oil embargos of the 1970’s made many nations aware of their dependency on controlled non-renewable energy sources and this fueled exploration of alternatives. This included research into renewable sources such as solar electricity, wind power and geothermal energy, all of which are free sources and nonpolluting, unlike oil and coal.
