Optimizing Liquid-Cooled Thermal Management Systems in Fuel-Cell-Powered Regional Aircraft

Proton exchange membrane fuel cell (PEMFC) powertrains have the potential to contribute significantly to the decarbonization of regional aircraft. Realizing the potential of these powertrains will require payload and cost parity with Jet A-1-fueled counterparts. In this paper, the OpenConcept toolkit for conceptual design of aircraft was employed with PEMFC technology benchmarks operating at low temperature (LT) 80°C and high temperature (HT) 160°C to optimize liquid-cooled PEMFC powertrains in regional aircraft for minimal fuel burn and to compute their payload capacity and associated fuel cost per revenue passenger kilometer (RPK) for comparison with Jet A-1. The outputs from OpenConcept were used to expediently assess the performance of PEMFC powertrains for different aircraft weights and mission ranges with a new metric that was derived from Breguet range theory. This paper provides important findings: first, the optimized powertrains were insensitive to mission range; second, HT-PEMFCs reduced fuel cost per RPK by 37% relative to LT-PEMFCs by 2035 and performed competitively with sustainable aviation fuel (SAF); and third, HT-PEMFCs increased payload by 51% compared with LT-PEMFCs. The Breguet range metric indicated that HT-PEMFCs will be the option most competitive with Jet A-1 by 2035, but to meet payload and cost parity, significant technological advances and policy initiatives are required.