Solar Energy Develpoment Part 2

"Solar technology advanced to roughly its present design in 1908 when William J. Bailey of the Carnegie Steel Company invented a collector with an insulated box and copper coils." By the mid-1950s Bell Telephone Labs had achieved 4% efficiency, and later 11% efficiency, with silicon PV cells. From then on, interest in solar power intensified. During the late 1950s and 1960s, the space program took an active role in the development of photovoltaics. "The cells were perfect sources of electric power for satellites because they were rugged, lightweight and could meet the low power requirements reliably." Unfortunately, the cells were not practical for use on earth due to the high cost of making them efficient and lightweight, so further research was necessary.
 

Solar energy may have had great potential , but it was left on the backburner whenever fossil fuels were more affordable and available. "Only in the last few decades when growing energy demands, increasing environmental problems and declining fossil fuel resources made us look to alternative energy options have we focused our attention on truly exploiting this tremendous resource." For instance, the US Department of Energy funded the installation and testing of over 3,000 PV systems during the 1973-1974 oil embargo. By the late 1970s, energy companies and government agencies had invested in the PV industry, and "a tremendous acceleration in module development took place." Solar energy improvements were again sought during the Gulf War in the 1990s.
 

Considering that "the first practical solar cells were made less than 30 years ago," we have come a long way.The profligation of solar professional companies designing unique and specific solar power systems for individual homes, means there is no longer an excuse not to consider solar power for your home. The biggest jumps in efficiency came "with the advent of the transistor and accompanying semiconductor technology." The production cost has fallen to nearly 1/300 of what it was during the space program of the mid-century and the purchase cost has gone from $200 per watt in the 1950s to a possible mere $1 per watt today. The efficiency has increased dramatically to 40.8% the US Department of Energy's National Renewable Energy Lab's new world record as of August 2008.