Waste Heat Recovery and Economic Operation Optimization of an Integrated Energy System Including Offshore Wind Power, Hydrogen, Methanol, and Carbon Capture

Utilizing offshore wind power (OWP) for hydrogen production not only provides a solution for wind power consumption but also effectively expands hydrogen sources. To address issues related to OWP for hydrogen production, storage, and efficiency improvement, an integrated energy system is constructed, including OWP, hydrogen production, hydrogen storage, carbon capture, and waste heat recovery. First, the structural model is established, and key equipments are modeled, using hydrogen-to-methanol conversion, methanol reforming for hydrogen production and fuel cell to build a hydrogen storage system, combining with carbon capture equipment to achieve the recycling and reuse of carbon resources. Second, to enhance system efficiency and optimize economic costs, a waste heat recovery unit is added to the system. Then, aiming at minimizing system operating costs and environmental impacts, corresponding objective functions are established. Finally, four different technical schemes are designed, and case simulations are conducted to compare and analyze the operational results. Results show that Scenario 4 with waste heat recovery is optimal, further significantly reducing the system’s total economic cost by $\mathbf{6. 6 2 \%}$ based on Scenario 3, verifying the scheme’s economic and high-efficiency advantages.