Life-cycle Assessment and Cost Analysis of Hydrogen Production via Aluminium-seawater Reactions

Presented is an evaluation of the carbon footprint and costs associated with hydrogen production via the aluminum-water reaction (AWR), identifying an optimized scenario that achieves 1.45 kgCO2 equiv per kg of hydrogen produced. U.S.-based data are used to compare results with conventional production methods and to assess hydrogen use in fuel-cell passenger vehicles. In the optimized scenario, major contributors include the use of recycled aluminum (0.38 kgCO2 equiv), aluminum processing (0.45 kgCO2 equiv), and alloy activator recovery (0.57 kgCO2 equiv). A cost analysis estimates hydrogen production at $9.2/kg when using scrap aluminum, alloy recovery, and recycling thermal energy, aligning with current green hydrogen prices. Reselling reaction byproducts such as boehmite could generate revenue 5.6 times greater than input costs, enhancing economic feasibility. The cradle-to-grave assessment suggests that aluminum fuel, as an energy carrier for hydrogen distribution and fuel cell vehicle applications, offers a low-emission and economically viable pathway for clean energy deployment.