• Techno-economic analysis of PEME heat recovery at six operating temperatures. • 28.8–41.3% of PEME input power converts to heat, varying with operating temperature. • PEME-DH efficiency rises 25.9–40.4% depending on source and sink temperatures. • LCOH2 ranges 5.76–8.43 €/kg by operating temperature and system configuration. • Selling heat at the same temperature as produced is recommended. This study investigates the technical performance and economic feasibility of waste heat recovery from PEME stack operating at six temperatures. Using real polarization curve data, key performance metrics such as PtH 2 efficiency, combined efficiency of PtH and H 2 , specific power consumption (SPC), recoverable heat and economic indicators like annual cash flow (ACF) and levelized cost of hydrogen (LCOH 2 ) were analyzed. Three business scenarios were modeled, considering dynamic district heating (DH) demand profiles and two heat delivery configurations: supplying heat to the DH return side (low price, typically without a heat pump) and the DH supply side (higher price, requiring a heat pump). Results show that raising operating temperature from 30 °C to 80 °C reduces SPC and increases PtH 2 efficiency from 49.3% to 59.8%, but decreases the share of recoverable waste heat, slightly lowering combined efficiency of PtH and H 2 from 89.7% to 87.4%. The LCOH 2 ranges from 5.76 €/kg to 8.43 €/kg, with a positive ACF achieved only in scenario 1 where all waste heat is sold to the DH return side. The most profitable operating temperature for the electrolysis plant is 60 °C, balancing efficiency and stack durability to achieve the lowest LCOH 2 . Scenarios involving partial heat sales or supply-side delivery generally yield negative cash flows, even with higher waste heat prices. The analysis concludes that integrating PEME stacks with DH systems is most viable when operating around 60 °C and delivering waste heat to the DH return side. This configuration maximizes technical performance, extends stack life, and improves profitability, providing a practical pathway for enhancing energy efficiency and economic returns in electrolysis-based hydrogen production.
Moradpoor et al. (Thu,) studied this question.