Page 117 - ΝΑΥΤΙΚΑ ΧΡΟΝΙΚΑ - ΜΑΙΟΣ 2023

Hydrogen as fuel is cryogenic, requiring storage, ridor’ concept is founded on the availability of low
transport and handling more complex than LNG and and carbon-neutral fuels at pre-determined points
therefore a completely new chain of supply, distribu- in the global supply chain, providing owners with the
tion, bunkering and handling. confidence that the fuels they need will be available
It is important to remember that such fuels are only to bunker their vessels.
part of the story. For example, ammonia is an effec- Ports can help to provide the locations, the facilities
tive carrier of hydrogen and can be used to provide and in some cases the carbon sources that could
the feedstock for hydrogen fuel cells. Such sys- be used to create a sustainable supply of blue and
tems have grown in size, scale and complexity from green hydrogen for production of ammonia and
providing auxiliary power to main engine power in methanol. Alongside their traditional cargo han-
smaller craft, sometimes in combination with battery dling and distribution functions this will increasingly
systems. include production sites for renewable fuels using
electricity produced from offshore wind and onshore
Considering that we are talking about green fuels, how is facilities that can create clean fuel.
the issue complicated by the need for green hydrogen to Numerous projects are already planned or under
produce green ammonia and green methanol? construction at ports ranging from Europe to the US
Critical to the maritime industry’s energy transition with others set to follow. The efforts by policymakers
are two related trajectories; the evolution of regu- around the world to transition the global economy
lation and the availability of renewable feedstocks to a sustainable footing will see projects of this type
from which to produce fully sustainable fuels. continue to grow and scale as we progress beyond
The International Maritime Organization is set to 2030 and closer to 2050.
further discuss the criteria under which it measures
carbon emissions, potentially moving from the cur-
rent (well-to-tank) measure to one based on the
lifecycle emissions of a fuel (well-to-wake). Though
these discussions are not final, they indicate a direc-
tion of travel towards lifecycle assessment and when
agreed and adopted, they will increase the pressure
on availability of green feedstocks for alternative
fuels.
At present the majority of alternative fuels are still
produced from fossil sources, so even though they
offer lower carbon emissions in service, their lifecy-
cle emissions will mean they have a higher overall
carbon contribution.
The greenhouse gas intensity of these fuels can be
dramatically reduced by deploying technology solu-
tions to reduce upstream process emissions, such as
capturing CO₂ to produce so-called ‘blue’ fuels as
an intermediate step.
Even if more of the fleet was able to able to use
alternative fuels available today, the vast majority
would be produced either directly from fossil fuels
or indirectly through carbon capture and recycling
into blue fuels.
The use of blue methanol for example could provide
time for capacity of green methanol production to
grow.
Ideally, the transition would be straight to green
fuels, but as the early adopters have discovered,
adopting alternative fuels requires securing the
supply chain that bears little comparison to current
bunkering practice. At present the availability of
feedstocks of green hydrogen are limited and where
they are available it is likely that offtake agreements
are used to allocate them.
Change is happening. The much-touted ‘green cor-

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