Test of a Mini-Mirror Array for Solar Concentrating Systems

Abstract

To reduce the construction costs of solar tower power plants an innovative new mirror system with mini mirrors is on the way as an uncommon alternative to the currently used heliostats with huge surface (actual up to 120m²). An about (0.6 x 0.6) m miniature test unit has now been con-structed. This first demonstration unit at first consists of a boxed array of 25 small parallel ar-ranged mirrors with a size of (10 x 10) cm each. All mirrors are linked by an agile, crossed stick stage with an integrated drive system to move them simultaneously into all necessary positions. This specimen, developed in cooperation with all partners, will be tested in the specially pre-pared artificial sun of the SIJ in different ways under changing conditions. In a simulation an optimum field layout was calculated. With this data a theoretical comparison was made between a typical existing huge heliostat and the developed mini-mirror array unit with respect to the efficiency and cost-performance relations for a solar tower power plant.