Energy, exergy, exergoeconomic, and environmental (4E) analyses of a combined system comprising reformed methanol high-temperature proton exchange membrane fuel cells and absorption refrigeration cycle

4E (energy, exergy, exergoeconomic, and environmental) analyses of a reformed methanol high-temperature proton exchange membrane fuel cell (RM HT-PEMFC) system identify inefficiencies, assess associated costs, and evaluate environmental impacts. However, such studies remain limited in the literature, particularly those exploring the impact of the operating parameters of the methanol steam reforming in the combined RM HT-PEMFC and single-effect absorption refrigeration cycle (ARC). This study addresses this gap by analyzing a tri-generation consisting of the RM HT-PEMFC and the single-effect ARC. Simulation results indicate a total exergy destruction of 21.65 kW, a total cost rate of 8.93 $/h, an exergoeconomic factor of 43.22%, and an exergy efficiency of 33.06% in the baseline case. Notably, the stack and burner account for the highest irreversibility, contributing 67.75% of total exergy destruction and 55.71% of the total cost rate. Parametric studies on four key variables–current density, stack temperature, reformer temperature, and steam-to-carbon ratio–reveal that higher system exergy efficiency is generally associated with lower carbon dioxide emissions. Uncertainty analysis shows that extending the HT-PEMFC’s lifespan to 40,000 h can reduce exergy cost per unit product by 16.23%, while decreasing the price of green methanol to 11.00 $/h can lower costs by 26.97%.