Solar receiver and associated energy conversion apparatus

Abstract

The disclosed invention relates to solar-thermal receiver tubes for heating high-temperature fluids such as molten salts and oils, such as those used in conjunction with trough reflectors or concentric concentrators. The disclosed invention utilizes fused silica receiver tube assemblies that provide optical absorption by way of optically-absorbing media that is imbedded within the thermal transfer fluid, preferably comprising inorganic 'dyes' that comprise pulverized thin film coatings or dissolved materials that are specifically designed for maximizing optical absorption. Alternatively, the chemistry of the transfer fluid can be modified to increase optical absorption, or the optically absorbing media may comprise fine powders with density preferably similar to the thermal transfer fluid, such as fine graphite powder; or, in another preferred embodiment, absorbing means within the heat transfer fluid comprise a solid absorbing element disposed along the central axis of the receiver tube's interior.