Sustainable integration of green hydrogen in refinery operations: HOMER-based simulation and scenario-based optimization for enhanced efficiency

This research conducts a detailed techno-economic evaluation and optimization of integrating green hydrogen into refinery operations. The study explores the feasibility of combining solar, wind, and biomass energy with an existing natural gas combined cycle power plant and grid connection to meet the refinery's substantial energy and hydrogen demands. It further investigates the use of renewable electricity to power an electrolyzer, partially substituting fossil-based hydrogen production in the reformer unit. Using a real refinery case study, ASPEN PLUS software simulates the electrolyzer and reformer units, while HOMER software models and optimizes the grid-connected system, refinery power generation setup, hybrid renewable energy components, reformer, electrolyzer, and hydrogen storage. The analysis incorporates both technical and economic parameters, such as energy costs, inflation, fuel prices, and environmental impacts to evaluate multiple operational strategies. The findings reveal that in the optimal sector-coupled scenario (Scenario 3), integrating green hydrogen into a hybrid energy system for the Esfahan oil refining company case study can lower CO2 emissions by 58.3% compared to the fossil-based baseline (Scenario 1) and reduce the net present cost from 12.3 billion $ to 10.3 billion $. These outcomes assume a natural gas price of $0.2/m3, electricity cost of $0.05/kWh, and an inflation rate of 38%. The results highlight the economic and environmental advantages of adopting green hydrogen in refinery operations. This research provides valuable insights into the design of green hydrogen systems for large-scale industrial applications, addressing challenges associated with energy reliability, cost-effectiveness, and environmental impact.