[extropy-chat] nano solar

[Damien Broderick]

Dunno if this is real news or not:


MIT Technology Research News

Los Alamos National Laboratory researchers have tapped nanotechnology to 
increase solar cells' potential energy production by as much as 37 percent.

Solar cells generate electricity by absorbing photons and directing the 
resulting energy to move an electron from the low-energy valence band in a 
material to a higher-energy conduction band where it is free to flow.

Researchers working to squeeze more energy from sunlight are generally 
aiming for solar cells that can absorb and use a higher percentage of the 
wavelengths of light in the sun's spectrum; today's commercial solar cells 
can use anywhere from 10 percent to 35 percent.

The Los Alamos researchers have found that it is possible to increase a 
cell's energy production by making each photon move two electrons. Key to 
the method is lead selenium nanocrystals that measure about ten nanometers 
in diameter, which is the span of 100 hydrogen atoms or 7,500 times 
narrower than a human hair.

The method could increase what has been thought of as the maximum power 
conversion of solar cells by as much as 37 percent depending on the 
materials used, resulting in a solar cell with a potential efficiency of 
over 60 percent. The method could also be used to make more efficient 
amplifiers, lasers, switches and light absorbers, according to the researchers.

Solar cells that use the researchers' method could become practical in two 
to three years, according to the scientists. The work is scheduled to 
appear in Physical Review Letters.