A novel solar power generation hybrid system comprising evacuated U-tube solar collector and thermally regenerative thermocapacitive cycle

Abstract

While solar energy offers a promising solution for sustainable energy, there’s a continuous drive to explore alternative methods of solar power generation. This paper introduces a novel solar power generation hybrid system that merges an angle-independent evacuated U-tube solar collector (EUSC) with a thermally regenerating thermocapacitive cycle (TRTC). Under AM 1.5 conditions, the hybrid system is anticipated to achieve a power density of 44.33 W m−2, accompanied by an efficiency of 4.43 %, underscoring its great prospect for practical applications. To unlock the performance potential, considerable parametric studies are conducted to find out diverse strategies to boost the hybrid system’s efficacy, encompassing the elevation of EUSC’s inlet temperature, reduction of external environmental temperature, moderation of fluid velocity within EUSC, and enhancement of thermal conductivity in the TRTC. Through meticulous optimization of thermal conductivity between TRTC and the environment, the hybrid system’s theoretical efficiency can attain a maximum of 9.38 %. A gradient-based local sensitivity analysis pinpoints that the EUSC’s internal fluid flow velocity is the most sensitive while the thermal conductivity coefficient between the TRTC and EUSC is the least sensitive. These results uncover key information critical for efficiently designing and operating the hybrid system.