Written By: Emma Websdale
Recent research in new materials for solar cells is making solar energy less expensive and more efficient, bringing it closer in cost to fossil fuels.
A new type of ceramic material that could make solar cells twice as efficient as those on the market today is being tested by a team of researchers from the University of Pennsylvania and Drexel University.
Their article, published in Nature, describes a ceramic material, made from a modified form of perovskite, with a crystalline structure that could make solar cells work twice as efficiently. The material is also less costly to produce than conventional solar cell material.
By using combinations of elements and molecules, researchers are making new perovskites in an attempt to make solar cells capable of converting over half of the energy they harness from sunlight directly into usable electricity. Operating at such high efficiency would mean a given amount of power could be produced by only half the currently needed number of solar cells.
Compared with conventional solar cell materials, the new material produces an electrical current without an electric field, thus reducing the amount of material needed to produce higher voltages and increasing power output.
Researchers of the technology have also demonstrated that modifying the new material to convert different wavelengths of light into electricity is also achievable. The idea is to build a solar cell with different layers. One layer splits up light and sorts it by color, then delivers the light to a second layer. The second layer contains an array of solar cells matched to the colors of the spectrum. This layering allows selected parts of the solar spectrum to be converted into energy immediately, making the cell much more efficient than conventional solar cells.
“We’ve opened up a new category of ways of making a solar cell”, says chemistry Professor Andrew M. Rappe, one of the authors of the report.
According to Technology Review, other scientists who have been developing the technology say that the new material could result in solar panels generating energy costing 10 to 20 cents per watt. On average, today’s solar panels generate energy costing 75 cents per watt. According to the U.S. Department of Energy (DoE), a cost of 50 cents per watt will allow the solar cells to compete with fossil fuels.
Also working on the new material is Martin Green, one of the world’s top solar researchers from the University of New South Wales, Australia. Green claims that work on the new material is making rapid progress. Solar cells that use the material, “can be made with a very simple and potentially very cheap technology, and the efficiency is rising very dramatically”, says Green.