Development and testing of advanced central receivers

The author discusses studies of advanced receiver concepts, such as the molten nitrate salt direct-absorption receivers and volumetric air receivers, which have shown their potential to be simpler and cheaper than conventional tube receivers. In a direct-absorption receiver, the heat-absorbing fluid (a blackened molten nitrate salt) flows in a thin, wavy film down a flat, vertical panel (rather than through tubes) and absorbs the concentrated solar flux directly. The volumetric air receiver design uses a porous absorber, on which the solar energy is concentrated. Air flows through the absorber, convectively transferring energy from the absorber to the air. In this work, the concepts, advantages, status, and test results of both the direct-absorption receiver and the volumetric receiver are discussed