MIT
Technology
Review
How ammonia could help clean up global
shipping
Ammonia is a familiar chemical for shipping companies. Globally,
about 200 million tons of it are produced annually, and about
three-quarters of that goes to producing fertilizer.
The fuel could provide an efficient way
to store the energy needed to power large ships on long journeys.
Getty Images
Ammonia might seem like an unlikely fuel
to help cut greenhouse-gas emissions. Best known for its odor, the
gas can be dangerous and toxic.
But it could also play a key role in
decarbonizing global shipping, providing an efficient way to store
the energy needed to power large ships on long journeys.
The American Bureau of Shipping, which
sets safety standards for global shipping, recently granted
early-stage approval for some ammonia-powered ships and fueling
infrastructure, including a design from
Samsung Heavy Industries, one of the world’s largest
shipbuilders. Such ships could hit the seas within the next few
years, as several companies have promised deliveries
in 2024. While the fuel would require new engines and new
fueling systems, swapping it in for fossil fuels that ships burn
today could help make a significant dent in global carbon
emissions. And some companies
are looking even further into the future, with New York–based
Amogy raising
nearly $50 million earlier this year to use the chemical for fuel
cells that promise even greater emissions cuts.
Shipping accounts for about
3% of global carbon dioxide emissions. If early tests for ammonia
or
other alternative fuels demonstrate scalable systems, these new
technologies could help the shipping industry start to shift away from
fossil fuels and slow the emissions that cause climate change.
Ammonia is attractive because of its high
energy density—the amount of energy that can be packed into a certain
volume. While it is usually found as a gas, it can be squeezed at
relatively low pressures into an easily transportable liquid.
Ammonia is a familiar chemical for
shipping companies. Globally, about 200 million tons of it are
produced annually, and about three-quarters of that goes to producing
fertilizer. Many ports already have some form of ammonia storage for
shipping.
The chemical, however, comes with
challenges. Burning ammonia as a fuel can create nitrogen oxides (NOx).
These compounds are greenhouse gases that can also harm human and
animal health, says
Madeline Rose, climate campaign director at Pacific Environment,
an environmental organization.
But if ships used ammonia for fuel cells
instead, the problem of creating NOx pollution could be avoided.
A fuel cell ship could contain ammonia
storage tanks, along with a reactor where ammonia would be broken
down to form nitrogen and hydrogen. The hydrogen would then be
shuttled to the fuel cell, where it would combine with oxygen to
produce water and the electricity used to power the ship.
Ammonia is cheaper to transport and
store than hydrogen, and cutting costs could make fuel cells
easier to adopt widely in the shipping industry. Amogy, the
startup company, demonstrated its reactor for turning ammonia into
hydrogen on a tractor earlier this year. The company plans to
scale its technology to larger vehicles like trucks and eventually
larger ships. But shifting an
industry as large as shipping to ammonia would require a major
growth in the supply of the fuel, says Amogy CEO
Seonghoon Woo. The global
market for ammonia production would eventually need to double or
even triple to keep up with potential demand, he estimates.
Most ammonia is produced today using
a century-old, energy-intensive process that relies on fossil
fuels. Production of green ammonia using renewable energy is still
limited, although industry giants like Yara, the world’s leading
ammonia producer, are working on demonstration projects to use
renewable energy or deploy carbon capture to cut emissions from
production.
Increased use of the new technology
in shipping could help bring costs down and encourage companies to
make changes. But countries and regulatory bodies like the UN
International Maritime Organization will likely also need to pass
legislation forcing shipping companies to cut emissions and
implement new technologies, says
Faig Abbasov, program director for shipping at the European
Federation for Transport and Environment.
There probably won’t be a single
solution to cutting emissions from shipping, says Pacific
Environment’s Rose. Decarbonizing an industry that big will also
require everything from increased efficiency to electrification to
new technologies, but cleaner fuels like ammonia could certainly
have a role to play.
Green Play Ammonia™, Yielder® NFuel Energy.
Spokane, Washington. 99212
www.exactrix.com
509 995 1879 cell, Pacific.
exactrix@exactrix.com
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