Beyond traditional boundaries: Exergo-economic and thermo-mechanical optimization of segmented thermoelectric generators with varied cross-sections

Abstract

In this work, we present a comprehensive optimization study of a concentrating solar segmented thermoelectric generator (CSSTEG) with variable area leg geometry. We consider not just geometrical parameters but also concentrated solar heat flux and convective cooling film coefficients, pushing the boundaries of traditional studies. Performance is evaluated on multiple fronts: power output, exergy efficiency, entropy generation, CO2 savings, dollar per watt, and thermal stress. Uniquely, we establish that an optimal skutterudite content of 6.17% provides maximum power output (47.47 W) and exergy efficiency (10.95%) at a solar heat flux of 50 kWm−2. This optimized configuration also delivers maximal annual CO2 savings (22.5 kgyr−1). Additionally, we pinpoint that a semiconductor height of 0.2 mm minimizes the dollar per watt (0.0048 $W−1) at 100 kWm−2 solar irradiances and reduces thermal stress (0.25 GPa) at a cooling heat transfer coefficient of 4 kWm−2 K−1. Our research is pioneering in its holistic approach to CSSTEG optimization, providing valuable insights for creating efficient, sustainable energy systems.

Keywords : Concentrating solar segmented thermoelectric, enerator, Variable area leg geometry, Solar heat flux, Cooling film coefficient, Comprehensive performance optimization