Finally A Photovoltaic That Really Delivers?
Solar photovoltaics is growing rapidly, albeit from a small base, to a total global capacity of 67,400 megawatts (MW) at the end of 2011, representing 0.5% of worldwide electricity demand. The total power output of the world’s PV capacity run over a calendar year is equal to some 80 billion kWh of electricity. This is sufficient to cover the annual power supply needs of over 20 million households in the world. More than 100 countries use solar PV.
Another day, another advanced use for graphene in solar photovoltaics. The first photovoltaic observations date all the way back to 1839 by Monsieur Becquerel, but it took until 1883 for American inventor Charles Fritts, to make the first solar cells made from selenium wafers. As with all pioneering technology, the first level of efficiency was very low. In 1923 Albert Einstein received the Nobel Prize for his theories explaining the photoelectric effect. By 1954, after much scientific effort at Bell Labs, solar PV had climbed to an efficiency of just 6%, although that excited scientists back them. One watt of electric power produced that way cost around $250, compared to $2-$3 per wat from coal.
By 1959 10% efficiency was achieved and the first commercial offerings were made to a rather dubious public. Under the spur of the cold war and the race to get men on the moon and probes into space and onto other planets, solar PV plodded along through the 60s and 70s turning from solar cells into solar panels along the way. By 2010, if costs no object, solar PV can get to an efficiency approaching 40%, according to the National Renewable Energy Laboratory (USA,) whose interesting chart is available at Wikipedia here.
Now it looks like graphene is coming to the rescue, thanks to the scientists at Michigan Technological University. If it’s scalable for mass production, the next generation of solar PV will be delivering efficiencies in the 50 percents. After that who knows the 60s or 70s.
Link: www.graphiteblog.com/2012/04/...taic-that-really-delivers.html