Authors
Wang, Yifan; Wright, Laurie

Abstract
Inland waterways are important for the transportation of goods and passengers. A significant contributor to economic development, emissions from vessels using these waterways are contributing to climate change, pollution, and other issues. Ambitious policies to reduce greenhouse gas, NOx and SOx emissions, require sweeping changes in propulsion and fuel technology. Hydrogen and electricity are recognised as pathways for vessel decarbonisation; however, mismanagement of production may increase overall lifecycle emissions. This study identified appropriate alternative fuel technologies for inland water transportation to mitigate climate change and deliver emission reduction over the fuel lifecycle. A comparative Life Cycle Assessment (LCA) was performed on marine gas oil (MGO), hydrogen and electricity propulsion systems, with multiple production pathways for an inland water sightseeing barge operating in northwest Europe. The assessment demonstrated that hydrogen and electrical propulsion technologies have potential for 85.7% and 56.2% lifecycle emissions reduction respectively, against an MGO base case. Implementation of both technologies is dependent on energy production pathways. Hydrogen systems reliant on fossil feedstocks risk an emission increase of up to 6.3% against MGO. Sensitivity analysis indicates renewable electricity to be the most promising pathway to achieve net-zero emissions operation, and with a potential to significantly reduce emissions over the vessel lifespan. Based on the UK average grid-mix in 2035, with a transition to 79.5% renewables, savings of 82.2% lifecycle GHG emissions are possible compared with MGO. There are significant challenges facing inland vessels and the wider maritime industry when selecting pathways for a low carbon future. Particular attention must be given to well-to-wake emissions when discussing the sustainability of any alternative marine fuel option to avoid burden shifting, or simply making the situation worse.