Japanese industrial majors, Mitsui OSK Lines (MOL) and Mitsui & Co have announced an approval in principle for a new design of ammonia-powered dry bulk carrier. Meanwhile, MOL has also announced that it has taken delivery of a methanol-powered methanol carrier.
Ammonia-powered approval
MOL announced that the approval in principle had been received from class society Nippon Kaiji Kyoka (Class NK) that has been designed by Mitsubishi Shipbuilding and Co. The Approval in Principle covers a 210,000 deadweight capesize dry bulker.
The engines on the new design would be powered by ammonia, which does not emit carbon dioxide during combustion.
By mass, ammonia has an energy density of 18.6 to 22.5 megajoules per kilogram whereas heavy fuel oil has an energy density of 39 to 42 MJ/kg. Accordingly, ammonia-powered ships will either have to have a smaller range, or bigger fuel tanks, or will have to find some other solution to maintain existing range. MOL / Mitsui’s new design calls for two ammonia tanks on deck to maximise the cruising range of the vessel to make effective use of cargo space for the carriage of cargo rather than fuel.
MOL’s new methanol carrier
MOL has taken delivery of the Cypress Sun, a dual-fuel methanol carrier that can run on either methanol or heavy fuel oil. The vessel will be chartered by MOL from Osaka Shipping Co, and Waterfront Shipping Company will charter the vessel from MOL under a long-term contract.
According to MOL, combustion of methanol can reduce sulphur oxide (SOx) emissions by up to 99%, particulate matter (PM) emissions by up to 95%, nitrogen oxide (NOx) emissions by up to 80%, and carbon dioxide (CO2) emissions by up to 15% in comparison to conventional marine fuel.
While methanol’s carbon emission performance is somewhat anaemic compared to zero carbon fuels, methanol can be made on an industrial scale using renewable energy and renewable feedstocks. The carbon in methanol (which has the chemical formula CH3-OH; one carbon atom connected to three hydrogen and also connected to a molecule comprised of one oxygen and one hydrogen atom) can be obtained from the digestion by microbes of a wide variety of biological wastes (such as agri-wastes, or forestry-wastes). The carbon that is emitted during combustion of methanol fuel therefore merely returns carbon to the atmosphere that had previously been drawn down from the atmosphere by plants during their growth phase.
MOL notes that it operates one of the world’s largest fleets of methanol carriers, with a total of 19 vessels (including the Cypress Sun), and it has been expanding the number of dual-fuel vessels, which can run on methanol, since 2016. Currently, MOL operates five of the 23 methanol dual-fuel tankers in service worldwide, including the Cypress Sun.
