Sharp solar cells can reach 60 percent efficiency

Solar power is perhaps the most well-known alternative source for power, but because of cost and the puzzles of physics itself, it is still quite far from becoming a completely sustainable and practical replacement. Sharp, however, may be on the breakthrough of creating solar cells that are twice as efficient as currently existing cells, at least in theory.

The main problem with solar power efficiency lies in the nature of sunlight itself and the laws of physics. When sunlight hits a solar cell, it emits high-energy electrons that are the bread and butter of such a process of converting solar energy into electricity. However, in just a few trillionth of a second, which already sounds impossible to imagine, the energy carried by those electrons are turned into heat, sunlight's by-product that is totally useless in this context. Whoever manages to address that will be able to solve the decades-old puzzle that has stumped many physicists working in this field.

Sharp's research team might have actually figured it out, thanks to exotic physics (yes, that's an actual term) and the understanding of materials that are used in manufacturing solar cells. In essence, the team was able to make a solar cell that is able to extract those high-energy electrons just before they become totally useless. This is a ground-breaking milestone in the science of solar energy as they are the first to have been able to harness these high-energy electrons to produce electricity. As such, the cell is theoretically capable of a conversion efficiency of 60 percent.

That sounds all good on paper, but unfortunately this cell remains only a prototype. For all its super abilities, the solar cell is actually far too thin to absorb more sunlight and is only limited to using only one wavelength of light when most existing cells can work with varying wavelengths available. Still, it's an important first step that could open the doors for more commercially viable solar cells similar to it.

SOURCE: MIT Technology Review