Dredging on liquid hydrogen: feasible or not?

Dredging vessels maintaining the Dutch coastline are responsible for 20% of the annual CO2 emissions of the Dutch Ministry of Infrastructure and Waterways, along with a significant percentage of NOx and particle matter emissions. In 2019, Rijkswaterstaat initiated Innovation Partnerships to drive innovations in the market. One such project involved Royal IHC collaborating with Rijkswaterstaat to develop a hydrogen-powered hopper dredger known as the LEAF-Hopper. The vessel is designed to be energy-efficient, utilizing liquid green hydrogen as its primary energy carrier and fuel cells for energy conversion.

The design of the LEAF-Hopper focuses on energy efficiency, with features like a wider vessel and a shallower draught to optimize dredging operations. The use of liquid green hydrogen and fuel cells was chosen after evaluating various energy converters and carriers. While the use of e-methanol was also considered, the project team determined that hydrogen was the most suitable option for the vessel. The decision was based on factors such as energy efficiency, operational requirements, and fuel availability.

Despite the higher costs associated with using liquid green hydrogen compared to traditional diesel, the environmental benefits of the H2-Hopper offset these costs. The vessel is expected to be about 60% more expensive to operate per cubic meter than a diesel-powered dredger but offers significant environmental advantages. The project also explores the feasibility of using e-methanol as a fuel alternative and addresses challenges related to bunkering and safety considerations for liquid hydrogen.

Looking ahead, the transition to more sustainable fuel options like hydrogen and e-methanol presents opportunities for the dredging industry to reduce its environmental impact. While there are concerns about the global market acceptance of vessels like the H2-Hopper, specialized and optimized solutions may be necessary for the industry to align with evolving energy regulations. Rijkswaterstaat recognizes the need for innovative approaches to ensure the dredging sector keeps pace with advancements in energy technology and environmental sustainability.