Reducing LCOE through measurement-based quality assurance and hybrid performance testing in solar fields

Low levelized cost of electricity (LCOE), higher revenues and lower expenditures are in the focus of all commercial CSP projects. In order to reach high performance in parabolic trough solar fields, the key components have to be of high quality and durability. The precision exigencies on the shape of the reflector surface in the order of tens of milliradians and the relative position of the absorber tube of concentrating collectors in the order of millimeters are unusually strict for constructions of this size, that typically exceed 70 square meters per module. To ensure high optical, mechanical and thermal performance of a complete solar field, specific quality assurance measures must be performed throughout the construction of a power plant, including early phases of the project such as the selection of adequate key components. Quality control measurements in the assembly line and spot check measurements in the solar field shall ensure accurate assembly and correct installation of the collectors [1]. For the enhanced verification of the solar field quality for final acceptance, comprehensive measurements with a large empirical basis taken from unmanned aerial vehicles [2] are recommended, before or while the thermal performance of the solar field is tested. This combined strategy is called hybrid testing. The paper gives an overview about quality management measures that finally lead to a high-quality solar field, lowering risks of failures, reducing ramp-up time and therewith contributing to lowering LCOE of parabolic trough power plants. A techno-economic evaluation shows that well-conceived quality control of solar field components leads to a higher overall plant performance, which results in additional revenues that pay back the additional efforts within a short time.