Page 208 - ΝΑΥΤΙΚΑ ΧΡΟΝΙΚΑ - SEPT 2025

Horizon from the bridge

As with most alternative fuels, ethanol has a 50% The IMO and other maritime bodies are
lower energy density than fossil fuels. Its energy still developing guidelines for regulating
density is also around 40% lower than biodiesel, alternative fuels such as ethanol, and fur-
which could impact engine efficiency and reduce ther clarity will be necessary to encourage
operating range, as ships may not be able to carry investment and adoption as part of the
enough fuel without larger tanks. IMO’s zero or net-zero (ZNZ) emissions
technology.

Delivery of ammonia bunkering
vessel in Singapore following
pilot ammonia bunkering trial
Fortescue, with support from the Mar-
itime and Port Authority of Singapore
edged challenges to its use in the marine (MPA) government agencies, research
sector. As with most alternative fuels, institutes, and industry partners, has suc-
ethanol has a 50% lower energy den- cessfully conducted the world’s first use
sity than fossil fuels. Its energy density of ammonia, in combination with diesel
is also around 40% lower than biodiesel, in the combustion process, as a marine
which could impact engine efficiency and fuel onboard the Singapore-flagged
reduce operating range, as ships may ammonia-powered vessel, the “Fortes-
not be able to carry enough fuel with- cue Green Pioneer”, in the Port of Sin-
out larger tanks. Any lower range would gapore. The vessel was loaded with
likely require consideration of the terms approximately 6.4 cubic meters of liq-
of time charter contracts, including speed uid ammonia from the existing ammo-
and performance guarantees. Ethanol is nia facility at Vopak Banyan Terminal on
also hygroscopic and can corrode tanks, Jurong Island for the fuel trial.
engines, pipelines, and valves not specif- In completing the fuel trial, the “Fortes-
ically designed for its use. Cleaning units, cue Green Pioneer” received flag
filtration, and transfer systems must also approval from the Singapore Registry of
be specifically designed to handle ethanol. Ships (SRS) as well as the “Gas fuelled
Biodiesel is more compatible with existing ammonia” notation by DNV to use
marine engine types (as a “drop-in fuel”), ammonia, in combination with diesel, as
but ethanol may require specially built or a marine fuel.
modified engines specifically for ethanol. Globally, ammonia is used in agriculture
Crew training and safety must also be and industry. It is manufactured as a
considered when using ethanol, as it chemical by combining nitrogen from
is a low flash point fuel (13-15°C), and the air with hydrogen. As a carrier for
vapours can accumulate, increasing the hydrogen, ammonia can be transported
risk of explosion if there is inadequate to demand centres for power generation
ventilation. The fuel also poses toxicity and as a marine fuel in support of the
and health hazards that require scenar- energy transition. Several dual-fuelled
io-based training, including vapour release ammonia vessels have already been
and emergency response. Ethanol fires ordered by shipowners.
also develop differently from hydrocarbon In preparation for the vessel’s opera-
fires and require specialised firefighting tions in Singapore, Hazard Identifica-
equipment, procedures, and personal pro- tion (HAZID) and Hazard and Operability
tective equipment. (HAZOP) study workshops were jointly
Contamination and spillage behaviour are organised by MPA, Fortescue, Vopak,
also factors that should be considered. research institutes, and industry partners
Ethanol is water-soluble and disperses to identify the potential risks during fuel
rapidly in the marine environment, but, transfer and engine trials and to develop
unlike oil, it does not form a surface slick, the necessary prevention, control, and
making physical recovery difficult. It is mitigation measures.
biodegradable, but rapid breakdown can Training sessions, including gas-spe-
reduce oxygen in the water, leading to cific hazardous materials emergency
hypoxic (low oxygen) conditions that are responses and MPA-led safety drills, were
harmful to marine life. also conducted to assess the operational

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