High quality heliostats leading to new optimal field layouts coupled with an asymmetric receiver geometry

The “High Performance Thermosolar Plants based on PV-Hybrid Autonomous Heliostats and Tailored Receivers” project (aka PHOTON project) aims to make substantial progress in cost reduction and performance for concentrating solar tower systems. The project counts with the financing support from Eurostars2 program, part of the European Union's Horizon 2020 Framework Program for Research and Innovation. Within the project, Tewer Engineering (Spain) is leading a consortium in close collaboration with project partners ACCIONA Industrial (Spain), Aalborg CSP (Denmark) and Protech-MetSolar (Lituania) to design optimized smart autonomous heliostat technology that enables new field-receiver designs and plant optimization strategies. The PHOTON heliostat combines intelligence and mechanical innovations that reduce the solar field construction complexity as well as it greatly simplifies commissioning operations through an automatic self-calibration feature. This paper focuses on one of the key findings of the project, the incidence of the high optical quality on the resulting optimized solar field layout, and its potential utilization for the benefit of the overall plant performance and economics. The simulation results have been compared to reference base cases representative of the State-of-the-Art technology at the project start. At the time of writing, the EPC cost reduction has reached a level of 14.41%, and the combination of the solar field, solar receiver and power block optimization has increased the global efficiency of the solar thermal electric plant 2.96%. An important reduction in LCOE in the range of 13% has been achieved for the best case evaluated.