Ultra thin solar cells can absorb sunlight more efficiently than silicon cells thicken and expensive to use today because light behaves differently about a nanometer scale, say engineers at Stanford. They calculate that correctly setting the thickness of multilayer thin films, a thin layer of organic polymer could absorb up to 10 times more energy from sunlight than you thought possible.
Clean, smooth and white, silicon wafers and solar cells, is that a little roughness can go a long way, maybe all the way to make solar energy an affordable energy source, say Stanford engineers.
That the light bounces around inside the polymer film of a solar cell behaves differently when the film is ultrathin. A film that is thin at the nanoscale and have been hurt a little can absorb more than 10 times the energy predicted by conventional theory.
The key to overcoming the theoretical limit is to keep the sunlight in the grip of the solar cell long enough to squeeze the maximum amount of energy from it, using a technique called “capturing light. “It is the same as if you were using small hamsters on wheels to generate electricity, you would like each hamster register as many miles as possible before bouncing away and escaped.
Black silicon for cheaper solar cells:
A simple chemical treatment could replace expensive anti reflective coatings for solar cells Reducing the cost of panels crystalline silicon. Treatment, a dip in a single step in a chemical bath, creating a highly anti-reflective coating black silicon on the surface of silicon wafers, and cost only pennies per watt, according to researchers at the National Renewable Energy Laboratory (NREL).
Researchers have used this to create black silicon solar cells that match the efficiency of conventional silicon cells in the market, but at a lower cost.
