Cost-Effective and Sustainable Pathways for Green Industrial Cogeneration: Replacing Natural Gas with Hydrogen in Dicastal's Operations

The industrial sector is a major contributor to greenhouse gas emissions, responsible for around 24% of global emissions in 2019. According to the World Resources Institute (WRI), to meet short-term climate targets aligned with a 1.5°C increase in global temperatures, the share of electricity in the final energy demand of the industrial sector must increase to 35-43% by 2030, 51-54% by 2040, and 60-69% by 2050.
CITIC Dicastal, the world’s largest producer of automotive aluminum wheels, operates 21 manufacturing facilities globally. These facilities, which collectively produce around 80 million aluminum wheels and 120,000 tons of aluminum castings annually, have significant energy needs due to their high-volume production. For instance, the newly opened plant in Morocco is designed to operate using green energy instead of relying solely on natural gas, utilizing high-temperature furnaces for aluminum alloy melting. This requires a reliable energy source to meet the plant's energy demands.
This study provides tailored recommendations for enhancing efficiency and reducing environmental impact by exploring cogeneration, where both heat and electricity are produced simultaneously. Renewable electricity from photovoltaic and wind sources is used, while water for hydrogen electrolysis is sourced from a water treatment station. For energy storage, batteries are employed for short-term storage, while hydrogen storage is utilized for long-term storage. A portion of the hydrogen produced is burned to generate heat, while the remaining hydrogen is used in a fuel cell to generate electricity. We compare different hydrogen combustion systems and green hydrogen technologies using a multi-scenario analysis approach.
We find that direct-fired systems are prioritized for processes requiring rapid heating, while indirect-fired systems are suitable for applications sensitive to direct flame contact. Fluidized bed combustion systems are effective for burning various fuels, including low-quality fuels. For CITIC Dicastal's decarbonization strategy, selecting electrolyzer technology should consider hydrogen production scale, purity requirements, and integration with existing processes. Alkaline electrolyzers are recommended for large-scale hydrogen production due to their cost-effectiveness and maturity. Proton Exchange Membrane (PEM) electrolyzers are ideal for applications requiring high-purity hydrogen and quick response times. Solid Oxide Electrolyzer Cells (SOECs) offer promising solutions in environments where waste heat can be utilized. We also find that compressed hydrogen storage is particularly advantageous for immediate energy needs, while liquid and solid-state options provide solutions for long-term storage and safety. The study indicates that PEM fuel cells offer quick response times ideal for backup power but come with higher costs. Alkaline Fuel Cells (AFCs) provide a lower-cost alternative but are sensitive to carbon dioxide. Phosphoric Acid Fuel Cells (PAFCs) are suitable for cogeneration but have longer start-up times. Molten Carbonate Fuel Cells (MCFCs) and Solid Oxide Fuel Cells (SOFCs) excel in efficiency, but face challenges related to high-temperature operations.
Overall, this research underscores the potential of integrating advanced hydrogen technologies into CITIC Dicastal’s operations to achieve significant decarbonization goals.