The UK Government has awarded funding to an ammonia-powered engine retrofit project, led by engine technology start-up Carnot and supported by Mitsui O.S.K. Lines (MOL), as part of the sixth round of the Clean Maritime Demonstration Competition (CMDC).
The initiative brings together MOL (Europe Africa), design consultancy Houlder, Clean Air Power GT, De Courcy Alexander, and the University of Southampton. The project aims to deliver a commercially viable ammonia-fuelled auxiliary engine retrofit that is capable of significantly reducing greenhouse gas (GHG) emissions across global shipping fleets.
Carnot’s engine architecture, which uses industrial ceramics to eliminate the need for active cooling, allows for ultra-high operating temperatures and improved fuel efficiency. By removing the energy losses associated with conventional cooling systems, the company has reported thermal efficiencies of approximately 70% when using diesel, significantly higher than those of traditional internal combustion engines. The ammonia retrofit will use this technology to offer a low-emission propulsion option for existing vessels.
The University of Southampton will support the project with combustion simulation modelling, while Clean Air Power GT is developing a high-flow ammonia injector to accommodate the fuel’s specific combustion characteristics.
Houlder will manage the integration of the system into existing vessel configurations, and De Courcy Alexander will assess commercial viability and market entry pathways. MOL (Europe Africa), which invested in Carnot in July 2024, will provide operational input and strategic oversight from a fleet deployment perspective. The project aligns with MOL’s ‘BLUE ACTION 2035’ plan, which focuses on supporting the transition to alternative fuels and reducing GHG emissions from its fleet operations.
The UK government is providing the support through the CMDC, which is part of the Department for Transport’s UK Shipping Office for Reducing Emissions (UK SHORE) programme. CMDC6 has allocated £30 million for early-stage trials and feasibility studies into low- and zero-emission maritime technologies. Since its launch in 2022, UK SHORE has committed over £230 million in funding and supported more than 300 organisations. Other recipients in the current CMDC6 round include UK-based wind propulsion developers GT Wings and Anemoi Marine Technologies, with the latter receiving £1.2 million in funding.
