Advancement News: Fall 2006
taming star power
• Taming Star Power
Researchers at Boston College have recently discovered a way of harnessing solar energy that has the potential to increase efficiencies by more than 100 percent – all at a cost per watt competitive with today's fossil fuel prices.
The key is nanoscience, which is the study of matter at the scale of a nanometer, or one-billionth of a meter. By manipulating the material through which sunlight passes (e.g., a thin layer of silicon), BC physicists have found that they can improve the material's photovoltaic efficiency, or the number of free electrons that escape from the silicon carrying an electric charge.
"In order to escape, the electrons have to withstand what is essentially a 50-mile-long demolition derby," notes Professor of Physics Michael Naughton. "That's why typically only 10 out of every 100 electrons manage to escape; the others crash and burn along the way. What we've done is find a way to shorten the distance of the demolition derby from 50 miles to 1 mile, which permits more electrons to be converted into electricity."
In collaboration with Zhifeng Ren and Krzysztof Kempa, fellow physics professors at BC, Naughton is experimenting with using coaxial cables – similar to those used to deliver cable television – to convert sunlight into energy. But instead of the copper and plastic used in TV cables, the researchers are incorporating silicon wafers that have been manipulated to increase their conductivity.
"This type of collaboration among scientists within one department is not common," notes Ren. "At Boston College, we've created an environment in which we can work together to accomplish much more than we could on our own."