PHOTOVOLTAIC SYSTEMS BASED ON SPECTRALLY SELECTIVE CONCENTRATORS

WE HAVE DEVELOPED A HOLOGRAPHIC DEVICE THAT GREATLY IMPROVES THE EFFICIENCY OF SOLAR ENERGY GENERATION. THE SINGLE-ELEMENT HOLOGRAM FOCUSES LIGHT TO THE SIDE AND ALSO SPECTRALLY SPLITS IT. THE OUTPUT APPEARS AS A THIN, CONCENTRATED LINE FOCUS PERPENDICULAR TO THE HOLOGRAM AND DISPLACED TO THE SIDE. DIFFERENT WAVELENGTHS ARE DIFFRACTED, CONCENTRATED, AND DISPERSED TO DIFFERENT LOCATIONS ON THE LINE. THE LINE RESEMBLES AN ELEGANT RAINBOW IN THE VISIBLE. THE HOLOGRAM LETS EACH OF TWO OR MORE DIFFERNT SOLAR CELLS ABSORB ONLY THOSE WAVELENGTHS THAT IT CAN EFFICIENTLY CONVERT TO ELECTRIC POWER. THE DEVICE ALSO PREVENTS OVERHEATING BY DIFFRACTING UNWANTED INFRARED AWAY FROM THE CELLS. THE SIDE FOCUS ELIMINATES SHADOW EFFECTS, AND COOLING IS EASY, SINCE THE CELLS ARE NOT CASCADED AND THE HEAT LOAD IS MINIMAL. THIS NOVEL SYSTEM IS IDEAL FOR CONCENTRATING, SPECTRUM SPLITTING, HIGH EFFICIENCY POWER GENERATION.