Recent technical and commercial developments have bolstered ammonia’s status as a marine fuel frontrunner
Because it contains no carbon, is easy to store and transport and is an efficient hydrogen carrier, ammonia is seen as one of the frontrunners in the marine future fuels race. Drawbacks to its use as a marine fuel are its relative low energy density and toxicity. Additionally, production would have to be massively scaled up to meet shipping’s need for green hydrogen, produced by renewables, or blue hydrogen, produced by using carbon capture and storage.
Still, such hurdles have not deterred the energy industry and marine stakeholders from collaborating on research and development to create a bunkering infrastructure at one of the world’s busiest ports for this promising future fuel.
One such effort is a joint study being undertaken by ABS, looking at the potential of ammonia as a marine fuel within Singapore’s bunkering supply chain. ABS is working with Nanyang Technological University (NTU) Singapore, and the Ammonia Safety and Training Institute (ASTI) to assess safety protocols and probe for possible gaps in the bunkering supply chain for ammonia as a marine fuel.
Initial partners in the study are to include ExxonMobil, Höegh LNG, MAN Energy Solutions Singapore, Jurong Port, PSA Singapore and ITOCHU Group, an ABS statement said.
“Ammonia is a fuel with significant potential for marine applications and ABS is leading the way in understanding challenges in the safe design and operation of ammonia-fuelled vessels,” ABS director of sustainability strategy Panos Koutsourakis said.
“It is also clear that Singapore has the potential to play a critical role as a strategic downstream location to receive, store, consume or bunker ammonia,” he said.
Two-stroke ammonia engine
MAN Energy Solutions vice president heading up research and development for the two-stroke side of MAN’s operation, Brian Østergaard Sørensen, said MAN sees ammonia as “a very interesting candidate as a zero-carbon fuel.”
Noted Mr Sørenssen: “A suitable engine technology is key and MAN Energy Solutions ... aims to deliver the first ammonia-fuelled, two-stroke engine in 2024. We look forward to adding our expertise to this study to the benefit of Singapore, which is such a vital shipping hub,” he said.
In October, MAN Energy Solutions said it was leading a consortium in Denmark to develop ammonia-fuelled, two-stroke engines for delivery to a shipyard by 2024.
Joining MAN in the Danish-funded AEngine project will be fuel supplier Eltronic FuelTech, the Technical University of Denmark (DTU) and class society DNV.
This project aims to demonstrate a large marine engine running on ammonia at MAN’s test facility, Research Centre Copenhagen. There will be three stages: concept development and initial design; design of an ammonia fuel-supply system; and finally, full-scale testing in Denmark.
Speaking at Riviera’s Maritime Air Pollution (MAP), Europe event in October, MAN Energy Solutions director of new technologies in the two-stroke promotion department Kjeld Aabo noted that ammonia does not have the same cryogenic storage and transportation hurdles as LNG or hydrogen.
Mr Aabo said ammonia could be stored at moderately low temperatures of -33°C and supplied at a pressure of 70 bars. It has specific energy of 18.6 megajoules (MJ)/kg and energy density of 11.5 MJ/L.
Ammonia membrane tank
Other pieces are falling into place for ammonia as a fuel. Leading French cryogenic containment technology firm GTT announced in February it had obtained an approval in principle (AiP) from Bureau Veritas related to the ‘NH3 Ready’ classification of its Mark III membrane tanks. The AiP recognises that the Mark III system, without any major design changes, is suitable for the subsequent containment of ammonia in LNG as fuel applications. Mark III containment technology is widely used for cargo containment in LNG carriers. While the primary barrier of Mark III technology was compatible, the containment system would require reinforcement to take into account the higher density of ammonia compared to LNG.
Commenting on the AiP for the industry’s first ammonia membrane tank system, GTT chairman and chief executive Philippe Berterottière said: “While we are convinced that LNG is the solution of choice for cleaning-up ship emissions even further, we have to take into consideration that ammonia, coming from green hydrogen, could bring additional reductions in emissions. In offering ammonia compatibility, we open the perspective to owners of a much longer period for ship amortisation.”
Confidence in ammonia as a fuel is such that one shipowner has already pulled the trigger on the construction of the world’s first ‘ammonia ready’ tanker.
Classed by ABS, the 274-m, 156,000-dwt Suezmax tanker ordered by Greece’s Avin International is now under construction at China’s New Times Shipbuilding, with options for two further vessels.
Currently conventionally fuelled, the vessel complies with the ABS ‘Ammonia Ready Level 1’ requirements, indicating it is designed to be converted to run on ammonia. All the ships in the project will also meet ABS ‘LNG Fuel Ready Level 1’ requirements.
“Ammonia is an interesting candidate as a zero-carbon fuel”
“It is a challenging time for shipowners looking to invest in modern vessels able to support fleet decarbonisation objectives throughout their life span,” said ABS senior vice president, global engineering and technology Patrick Ryan. “ABS’ alternative fuel-ready suite of guidance and qualification programmes is designed to give owners the flexibility they need and help prepare for a future in which alternative fuels, such as ammonia, take a bigger role,” said Mr Ryan.
He added: “Ammonia is a promising zero-carbon fuel that can help meet IMO’s greenhouse gas emissions reduction target for 2050. It offers shipowners and operators a zero-carbon tank-to-wake emissions profile, but is not without challenges, not the least of which is the greater prescriptive requirements for containment and equipment than most of the other alternative fuels under consideration.”
Avin International technical manager Michael Androulakakis said: “The shipowners, seeking early decarbonisation of their fleet, which LNG fuel operations alone are not enough to fully achieve, have additionally invested in making the vessels ready for ammonia fuel. This currently appears to be one of the most widely available and most promising carbon neutral fuels for the future.”
In February, Euronav announced it had acquired two LNG-ready, dual-fuel suezmax tanker newbuilds at South Korea’s Daehan, with an eye towards converting them to burn ammonia at a future date. The tankers will be delivered in 2022.
Japan’s largest power generation company, JERA, wants to produce zero CO2 emissions from its operations by 2050, and it believes ammonia could help it achieve this goal. Producing about 30% of the country’s electricity, JERA inked a memorandum of understanding (MOU) with Malaysia state energy company Petronas to co-operate in promoting the use of LNG in Asian countries and in establishing supply chains for ammonia and hydrogen fuels. Petronas is a leading producer of ammonia in Asia and is considering the production of green ammonia and hydrogen, while JERA believes there are many sectors involved in LNG and decarbonisation in which both companies can collaborate.