Step towards sustainability: Techno-economic optimization of a parabolic trough solar collector using multi-objective genetic algorithm

Two parameters can make a technology desirable for industrial usage: high efficiency and low cost. With this aim, in this investigation, the geometric and design parameters of a parabolic trough solar collector (PTSC) have been examined and optimized with the dual goal of maximizing efficiency and minimizing the levelized cost of heat energy (LCHE). It is revealed that shuffling the types of design parameters like heat transfer fluid (HTF), absorber material, and solar selective absorber coating (SSAC) has a considerable impact on thermal performance and LCHE of PTSC. Also, a variation in geometric specifications (collector focal length, dimensions of absorber, collector, glass cover) can have both positive and negative effects on efficiency and LCHE. A multi-objective genetic algorithm (MGA) is utilized to find the set of design parameters and geometric specifications for PTSC that maximizes efficiency and minimizes LCHE. Combinatorial optimization is performed at two different tem-peratures to identify the optimal configuration of design parameters from a pool of 144 possible combinations comprising 6 SSACs, 6 HTFs, and 4 absorber materials. It was found that using the identified set of design pa-rameters, thermal efficiency can increase by 10 % at 100 degrees C and 6 % at 250 degrees C, with corresponding LCHE reduction of 13 % at 100 degrees C and 8.5 % at 250 degrees C. Additionally, an optimal set of geometric specifications is searched by varying the dimensions of PTSC. An improvement of >= 4 % in efficiency and a decline of >= 5 % in LCHE is noted with optimized geometric dimensions of PTSC.