Synergy between a methanol reforming process, fuel cell, and organic Rankine cycle: Multi-objective optimization of a next-generation energy system

Abstract

Optimizing multiple advanced energy technologies within an integrated system to enhance performance and sustainability is a significant challenge. This study presents a novel hybrid energy system integrating sorption-enhanced chemical looping reforming of methanol (SECL-OSRM), a high-temperature proton-exchange membrane fuel cell (HT-PEMFC), and a recuperative–regenerative organic Rankine cycle (RR-ORC). A comprehensive process model was developed, and a multi-objective optimization (MOO) was performed by coupling Non-dominated Sorting Genetic Algorithm II (NSGA-II) with the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method to maximize system efficiency while minimizing exergy destruction and total system cost rate. The best compromise solution, achieving a system efficiency of 42.04%, exergy destruction of 148.1 kW, and a total system cost rate of 11.67 USD/h, was obtained with CuO/CH₃OH and MgO/CH₃OH molar flowrate ratio of 0.5, a current density of 0.806 A/cm², an oxygen flowrate ratio of 4, a fuel cell temperature of 200°C, and an intermediate pressure of 9 bar. This study highlights an ideal framework for efficiently optimizing a hybrid energy system. It offers comprehensive information about the interactions between system components and parameters to help establish a new understanding for developing the next generation of advanced energy systems.