Rethinking Maritime Carbon Capture: Onshore versus Onboard Solvent Regeneration

Ship-based carbon capture (SBCC) presents a promising pathway for decarbonizing maritime transport. Current demonstration projects typically adapt land-based capture technologies, which may not be optimal for maritime applications. This study proposes a novel onshore regeneration SBCC scheme, where CO₂-rich solvents are stored onboard and regenerated onshore, substantially reducing onboard complexity and fuel consumption. We comparatively assess this onshore scheme against conventional onboard regeneration across 16 major shipping routes, evaluating four solvents under varying SBCC load limits and projected carbon taxes (2030, 2040, and 2050). Results favor adopting practical load limits (~ 20%) rather than targeting fixed capture rates, using high-absorption-capacity solvents for onshore regeneration and low-regeneration-energy solvents for onboard regeneration. The onshore scheme is more cost-effective in most scenarios. An extended analysis of 357 global shipping routes indicates that SBCC becomes economically viable in 2040 and highly advantageous by 2050, reinforcing the significant long-term potential of the proposed onshore regeneration approach.