US Department of Energy: new action plans for decarbonizing transport

Working with other government agencies and key industry stakeholders, the United States Department of Energy has produced a series of action plans and technical reports for the decarbonization of transport sectors across the US economy. Rail, aviation, light, medium and heavy road transport are all addressed, but it is the marine action plan that will be of most interest to readers at Ammonia Energy.

Vehicles move us and our economy. The transportation system’s trucks, ships, trains, and planes move 55 million tons of goods, worth more than $49 billion, and transport people across 3 trillion vehicle miles annually. Transportation is core to how we live, work, and play, but also accounts for air pollution, increasing the risk for asthma, heart disease, and other health issues, especially in communities near highways, ports, rail yards, and warehouses. The transportation sector is also the largest source of greenhouse gas emissions and is the second-highest expense in U.S. households. We can address these challenges through innovative transportation technologies while building a stronger economy and healthier communities with good-paying jobs, more customer choice, domestic manufacturing, and secure supply chains.

From the United States Department of Energy’s official announcement, 12 Dec 2024

Marine decarbonization plan includes significant role for ammonia fuel

Click to enlarge. Ammonia fuel will play a significant role in the decarbonization of US ocean-going vessels by 2050. Fig ES-4 From An Action Plan for Maritime Energy and Emissions Innovation (US DoE, Dec 2024).

The marine action plan is split between ocean-going, harbor craft, defense and non-commercial vessels. Although non-commercial, personal use vessels make up more than 99% of vessels by number in the USA, the biggest of these in terms of energy consumed and stack GHG emissions is ocean-going vessels. The action plan urges prioritizing the implementation of electrolytic ammonia and methanol fuel in ocean-going vessels by 2050, with a smaller role for biofuels (including as a pilot fuel). A key part of this will be the US federal government developing and adopting a formal definition of “Sustainable maritime fuel” in 2025. An RFI is now open until February 2025 for feedback on what qualifies as an SMF.

There are several constraints to this action plan unique to the USA. The annual replacement rate of vessels in the USA is very low, as is (compared to global numbers) annual vessel construction, especially for large ocean-going vessels. Retrofits, upgrades and drop-in fuel replacements will be key strategies moving forward, and the authors report that interviewed vessel owners would prefer retrofits that feature “backwards compatibility” (i.e. ability to still combust conventional fuels). This in turn helps alleviate any concerns about availability of new fuels, or any lack of infrastructure to supply them. Supporting key ports to deploy ammonia & methanol bunkering infrastructure is a recommendation of the action plan, as is revitalizing US shipyards to construct new, lower-emission vessels.