More and more solar photovoltaic (PV) are appearing on rooftops, but they are not necessarily the best solution in terms of solar power.
“The great limitation of photovoltaic panels remains that they can use only part of sunlight, the rest coming to be transformed into heat, which harms panels performance,” said Robert Taylor, a graduate student in engineering mechanics of the State University of Arizona.
An alternative which would cover up to sunlight, including light that PV can be used, is the solar heat. The purpose of these sensors in the form of parables, signs, vacuum tube, or tower is to collect solar heat, which can then be used to boil water, thus causing the steam to a final generator producing electricity.
To further increase the efficiency of solar collectors, Robert Taylor and his colleagues have mixed nanoparticles of the size of a billionth of a meter in heating fluids, usually used in thermal solar. The researchers chose graphite nanoparticles, in part because they are black and absorb light very well, making heat sensors more efficient.
In laboratory tests with small sensors dishes, the researchers found that nanoparticles increase efficiency of the collector heat up to 10%. “We believe that this would represent up to 3.5 million more revenue per year for a 100 megawatt solar power plant,” He said.
Moreover, adds R. Taylor, graphite nanoparticles “are cheap” (less than $1 a gram). Thus, 100 grams of nanoparticles offer the same capture surface heat equivalent to a football field. “It could also be possible to filter soot nanoparticles, which have a similar potential for absorption from coal power plants for use in solar systems,” he added. “I think this idea is particularly interesting to use a pollutant to produce a clean and renewable energy.”