Localized Solar Collectors

摘要

A localized heating structure includes a spectrally-selective solar absorber, that absorbs incident solar radiation and reflects at wavelengths longer than 2 μm, with an underlying heat-spreading layer having a thermal conductivity equal to or greater than 50 W/(mK), a thermally insulating layer, adjacent to the spectrally-selective solar absorber, having a thermal conductivity of less than 0.1 W/(mK), one or more evaporation openings through the spectrally-selective solar absorber and the thermally insulating layer, and an evaporation wick, disposed in one or more of the evaporation openings in the thermally insulating layer, that contacts liquid and allows the liquid to be transported from a location beneath the thermally insulating layer through to the spectrally-selective solar absorber in order to generate vapor from the liquid. The thermally insulating layer is configured to have a density less than the liquid so that the localized heating structure is able to float on the liquid.

主权项

1. A localized heating structure for use in solar thermal systems, the structure comprising:
a spectrally-selective solar absorber configured to absorb incident solar radiation and to reflect at wavelengths longer than about 2 μm, with an underlying heat-spreading layer having a thermal conductivity equal to or greater than about 50 W/(mK); a thermally insulating layer adjacent to the spectrally-selective solar absorber, the thermally insulating layer having a thermal conductivity of less than about 0.1 W/(mK); one or more evaporation openings through the spectrally-selective solar absorber and through the thermally insulating layer; and an evaporation wick disposed in one or more of the evaporation openings in the thermally insulating layer, the evaporation wick configured to contact liquid and to allow the liquid to be transported from a location beneath the thermally insulating layer through to the spectrally-selective solar absorber in order to generate vapor from the liquid, the thermally insulating layer configured to have a density less than the liquid so that the localized heating structure is able to float on the liquid.