One of the main reasons why alternative forms of energy production such as solar, wind, and geothermal power are not common today is the fact that they carry very high prices. In addition, obtaining energy from solar plants, wind farms and geothermal stations is an inconsistent process, in the sense that the amount of energy produced varies with each passing day. A new achievement could soon change all that, and allow solar power plants to make use of both heat and light coming in from the Sun at the same time. This could make solar energy competitive with oil-derived electricity.
The innovation was achieved by a team of engineers at the Stanford University. The experts believe that their approach could make solar energy production twice as efficient as it is today. One of the things that stands out about the new method is the fact that it excels at higher temperatures. This is unusual for existing photovoltaic technologies, which lose some of their efficiency as temperatures increase. And this is a phenomenon that is intimately linked with producing electricity from solar sources.
“This is really a conceptual breakthrough, a new energy conversion process, not just a new material or a slightly different tweak. It is actually something fundamentally different about how you can harvest energy,” says Stanford assistant professor of materials science and engineering Nick Melosh. He was also the leader of the research group that made the achievement possible.” The process itself is called photon enhanced thermionic emission (PETE). “Just demonstrating that the process worked was a big deal. And we showed this physical mechanism does exist, it works as advertised,” Melosh says.
The Stanford group published details of its new technique in the August 1 online issue of the esteemed scientific journal Nature Materials. “What we've demonstrated is a new physical process that is not based on standard photovoltaic mechanisms, but can give you a photovoltaic-like response at very high temperatures. In fact, it works better at higher temperatures. The higher the better. The PETE process could really give the feasibility of solar power a big boost. Even if we don't achieve perfect efficiency, let's say we give a 10 percent boost to the efficiency of solar conversion, going from 20 percent efficiency to 30 percent, that is still a 50 percent increase overall,” Melosh concludes.