Efficient harvesting of low-grade waste heat from proton exchange membrane fuel cells via thermoradiative power devices. (1st November 2022)

• Record Type: Journal Article
• Authors: Zhang, Xin; Li, Jingwen; Xiong, Yi; Ang, Yee Sin
• Is Part Of: Energy. Volume 258(2022)
• Publication Date: 2022-11-01
• Subjects: Hybrid electric power system -- Waste heat recovery -- Thermoradiative power device -- PEM fuel cell -- Performance optimization; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2022.124940
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: A hybrid electric power generation system involving a thermoradiative power device (TPD) and a proton exchange membrane fuel cell (PEMFC) is proposed, in which the TPD can efficiently convert low-grade waste heat produced by PEMFC into electricity. Accordingly, a theoretical model is developed to investigate the output performance characteristics and the optimal design of the proposed system. The model predicts that the hybrid system can generate a maximum power density of 0.367 W/cm 2 when operated at 353.15 K, possessing better output performance than other previously proposed PEMFC-based hybrid systems. The peak power density of the hybrid PEMFC-TPD device is around 1.30 times that of the PEMFC, suggesting significantly improved overall performance of the system. Additionally, the effects of radiative extraction efficiency and bandgap for the TPD to achieve optimal performance are investigated. Importantly, the optimal operating regime and the critical parameter designs concerning the hybrid system are identified, offering theoretical guidance for improving system performance. These findings provide important guidelines in designing high-performance coupled heat-to-electricity energy harvesting systems. Highlights: A PEMFC-TPD hybrid system for efficient waste heat recovery is proposed. Overall performance is greatly improved compared with the single PEMFC. The optimally operating regions and parameter choice criteria are determined. Optimal performance is superior to other PEMFC-based hybrid systems. The present work is of great importance to design and optimize the hybrid systems.