Solar field heliostat selection based on polygon optimization and boundaries

Abstract

A novel methodology for the design of heliostat fields is presented, based on the selection of heliostats from an oversized field by means of a polygon. To obtain the ideal field shape, the polygon vertices are optimized with an evolutionary algorithm. The objective function calculates a weighted tradeoff between annual optical efficiency and ground usage and is applied to the entire field instead of individual heliostats. Various other figures of merit could be readily integrated. To be able to deal with complex shaped land available for the Solar Tower plant, area boundaries are taken into account during the optimization phase. The application of the methodology is demonstrated by means of a reference scenario and multiple variations of parameters and area boundaries. The polygon selection creates smooth, coherent heliostat fields with high performance regarding the objectives, while solving several practical issues in the heliostat field design phase at the same time.