Tech We Needfuel—at $600 or $700 a ton, compared to
$400 a ton for heavy fuel oil. And that rule is
just a foretaste of a massive transformation
that is bearing down on Eefting’s industry.
Since the 1990s, ship owners have come
under intense pressure to pollute the planet
less. Container ships are indispensable to
trade, and there’s no greener mode of trans-
port to move a freshly riveted pair of jeans
from China to the US. But the world’s 90,000
or so cargo ships contribute between 2 per-
cent and 3 percent of all greenhouse gas
emissions—more than the share contrib-
uted by Canada or Germany.
While the sulfur cap is hitting shippers
now, the far more daunting and impressive
target is 30 years away. By 2050, the United
Nations’ International Maritime Organi-
zation (IMO) has stipulated, the shipping
industry’s total emissions must be at least
half of what they were in 2008. That goal is
even more ambitious than it might sound.
Trade will continue to grow even as 2050
approaches, says Johannah Christensen, the
managing director of the nonprofit Global
Maritime Forum. There will be many more
ships at sea, making many more journeys,
than there were in 2008. “What that trans-
lates to is actually an 85 percent reduction
in emissions intensity per ship.”
Meeting the deadline will require the
industry to spend as much as $1.4 trillion on
new fuel research and production, rejigged
supply chains, and a revamped fleet—and
no one even knows which solutions will
work. The ambition, Christensen says, is
“like a moon shot.”
In some ways, it’s easier to decarbonize
shipping than, say, automobiles or cement.
The number of cargo ships in the world is
small enough for them to be individually
tracked, and they live so much of their lives
in public—being inspected in one interna-
tional port or another—that they can’t slyly
break rules the way a cement plant in a
corrupt country might. Further, the ships
are already regulated by a central author-
ity: the IMO. The nature of this industry—in
which ship owners routinely register their
vessels under the flags of small countries
with lax regulations—also means that the
IMO is the rare forum where island nations
threatened by rising seas hold significant
sway. “Depending on the day you look at
it, the Marshall Islands is the second- or
third-largest flag register in the world,”
says Bryan Comer, a senior researcher at
the International Council on Clean Trans-
portation. “And they were instrumental in
making the moral argument for reducing
emissions at the IMO. If they’d had their way,
in fact, they’d have wanted a 100 percent cut,
and much before 2050.”
Even so, it’s an unusual challenge for an
industry to adopt an emissions target while
having no clear notion of the technologies
that will get it there. Borrowing ideas from
other sectors isn’t practical. Batteries are out.
A container ship crossing the Atlantic would
need so many batteries that it would have
no room left for containers. Nuclear power,
too, is dead in the water—“for political rea-
sons,” says Simon Bennett, the deputy sec-
retary general of the International Chamber
of Shipping. “The idea of foreign ships com-
ing into your port with a nuclear reactor on
board—that just won’t be acceptable.”
The solution most immediately at hand,
liquefied natural gas, emits less carbon diox-
ide than fuel oil, and ship engines can be
retrofitted fairly easily to burn it. But carbon
emissions from liquefied natural gas are only
about 30 percent less than from heavy fuel
oil. What’s more, the primary component
of liquefied natural gas, methane, is highly
prone to “slip,” or leak. Atmospheric meth-ane traps 86 times more heat than carbon
dioxide over a 20-year period. At best, says
Eefting, liquid natural gas is only a tempo-
rary answer—an intermediate station on a
zero-carbon pathway.
The fuels with more long-term promise
are ammonia and hydrogen, which, when
burned, release no carbon emissions at
all. MAN plans to deliver its first ammonia
engine in 2024. But there’s still plenty to be
figured out: To be truly green, these fuels will
themselves have to be manufactured with
no carbon footprint—something the IMO
can’t regulate. Ammonia production is one
of the most carbon-intensive processes in
industrial chemistry and is the subject of its
own slogging race for sustainable modifica-
tions. Meanwhile, ships and ports will have
to devise new ways of handling and storing
ammonia, given how toxic it is to humans.
“Plus, you have to remember,” Eefting says,
“ammonia stinks very much.” Hydrogen,
for its part, is highly flammable and would
require huge, special tanks. “Its molecules
are so small that they can leak out of virtu-
ally anything,” Eefting adds. “And you need to
compress it or cool it to minus-253 degrees
Celsius to have a decent energy density.”
The year 2050 isn’t so distant. Ships have
such long life spans that, for the fleet to be
ready in time, new vessels entering the water
as early as 2030 must already be configured
for zero-carbon fuels. More than the tech,
though, it’s the IMO’s model of curbing emis-
sions that feels both uncommon and import-
ant: Lay down the standards first, regulate
the consumers—the ship owners—and trust
that they’ll compel their fuel and engine sup-
pliers to invest and innovate. Tristan Smith,
a low-carbon shipping expert at Univer-
sity College London’s Energy Institute, says
that the response since IMO adopted these
targets has been extraordinary. “The speed
with which energy manufacturers have
moved, ammonia suppliers have moved,
ship owners have moved—nobody would
have believed it 18 months ago.” If the model
succeeds—if it isn’t subverted by fossil-fuel
giants or cheating ship owners—it’ll hold a
lesson for other sectors, Smith says. “When
you regulate sensibly, the market will sup-
ply the answers.”SAMANTH SUBRAMANIAN (@Samanth_S)
is a writer based in the UK and the
author of A Dominant Character.↙
Silicon Valley, if you’re listening here’s
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An Instagram algorithm that boosts
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Local, lab-grown bananas.