Thermo-economic and exergy analysis and optimization of small PTC collectors for solar heat integration in industrial processes

Abstract

This work presents an extensive analysis of the impact of operating and design parameters on thermo-economic and exergy performances of Small Parabolic Trough Collector (SPTC). The modeling equations system is developed based on thermodynamics and heat transfer phenomena, and it is resolved using a double fixed-point iterative algorithm and validated using experimental data from the literature. Moreover, an optimization work complete this study by using a new combined Fixed Point-Genetic Algorithm optimization method considering Rabat region (North: 34°00′47″, West: 6°49′57″-Morocco) as a case study. The objective function is expressed in such a way to minimize the total yearly cost of energy and maximize the collector exergy efficiency of the SPTC. The obtained outcomes of this work show that thermo-economic and exergy performances of the SPTC could be improved by reducing the collector length and receiver diameter and increasing the collector width. However, the mass flow rate of the heat medium impacts these performances differently. The optimization results prove that the integration of SPTC in industrial heat processes is a promising and very economical way to replace fossil fuels. Indeed, each single optimized SPTC (Aa = 10 m2; Width*Length = 2 m × 5 m) provides more than 12.84 MWh/year with an average unit cost less than 0.022 USD/kWh.