Point-focus multi-receiver Fresnel loop - Exploring ways to increase the optical efficiency of solar tower systems

Abstract

For commercial solar tower systems of relevant size, state of the art of light collection and concentration (LCC) subsystems (heliostat field plus receiver envelope) do not achieve annual optical efficiencies larger than 65%. Achieving optical efficiencies substantially higher than that requires departing from the traditional mono-tower design. Although multi-tower systems were identified long time ago as candidates to achieve high annual optical efficiencies, so far no multi-tower concept has emerged as a clear alternative to the mono-tower system. In this article, we introduce a variant of the multi-tower concept that combines the modularity and high land coverage of linear focusing technologies with the low thermal losses and high operating temperatures of solar tower technology, and overall represents a disruptive departure from the traditional mono-tower design.