The influence of transients on the design of DSG solar fields

Abstract
The Direct Steam Generation process (DSG) in parabolic trough solar power plants has a large potential to increase efficiency and to reduce cost of solar production of electricity, by generating live steam for the turbine directly in the absorber pipes. Three different modes are known to operate DSG solar fields. From these the once-through mode promises the lowest investment costs and consequently was investigated in detail during recent years. Its feasibility has been proven in several reduced-scale experiments, and schemes for process control were developed and analyzed. The results show that stable outlet conditions can be secured when the design of the solar fields accounts for the local weather conditions. The important effect of the transient conditions on the design is explained in this paper.