9781422282908

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Science and Energy

to prove that the dynomak will safely and efficiently produce energy, at a cheaper cost than a coal-fired plant. “Right now,” Jarboe said in a University of Washington press release, “this design has the greatest potential of producing economical fusion power of any current concept.” Building Better Solar Panels The idea of collecting energy from the sun to create electrici- ty isn’t new. In 1839, a young French scientist named Edmond Becquerel exposed certainmetal electrodes to light and created small amounts of electricity. The substances absorbed the light and then released electrons, which can be captured to create an electric current. Becquerel’s discovery was later called the photovoltaic or photoelectric effect—“photo” referring to light. Today’s solar panels are made up of individual units called pho- tovoltaic cells,which typically use silicon to capture sunlight and convert it to electricity. But as with the materials Becquerel used in the 19th century, silicon is not completely efficient at turning all the sun’s energy into electricity. The cells used in the typical home solar panel might be able to convert just 15 percent or so of the energy into a usable form. Scientists, though, think a new kind of material can make solar cells that are more efficient and cheaper than current photovoltaic cells.The new cells are made from materials called hybrid perovskites. In experiments in the lab, scientists learned that perovskites that contained a halide compound (halogen mixed with one of a number of different elements) had photoelectric properties.