Silicon is a very useful material thanks to its semiconducting properties. These not only allows for modern electronics but also some forms of solar panels. Unfortunately silicon is not always cheap as solar panels need highly purified silicon. This alone can account for 40% of the cost of modern solar cells. Researchers at MIT recently found a way to reduce the thickness of silicon used by 90% without sacrificing much efficiency.
The battle between cost and efficiency for solar panels has been going on for about as long as they have existed. This has led to the development of solar panels that use cheaper materials than silicon, but silicon still offers the highest efficiency. Researchers have considered shaving off some thickness to the silicon, to cut costs, but the thinner the silicon the fewer photons it can trap. The MIT researchers got around this by making pyramid-shaped indents in the silicon. This texturing increases light absorption of the cell without greatly increasing the surface area, which is important. The more surface area there is the more likely electrons are to lose their energy.
This new design has not yet been tested, but the researchers expect it will be able to convert 20% of the light that hits it into electricity. That is respectably close to the 24% we see with the most efficient silicon solar panels currently on the market. If this textured design ever comes to market itself, it will come without a great additional cost, because the tools used to etch the texture are standard equipment for etching silicon already.