To keep below the threshold of 1.5 degrees C of warming –
the goal of the Paris climate agreement – immediate reductions in carbon
emissions are needed. The International Maritime Organisation (IMO), the UN
shipping regulator, has put issues surrounding shipping and climate change high
on its agenda.
Shipping emissions can be calculated using four principal
factors: the weight of products transported, the distance they’re sent, the
amount of fuel it takes to move one tonne of products one kilometer, and the
amount of carbon released by making and using that fuel – known as the fuel’s
carbon-intensity.
The overwhelming focus of political attention is mainly on
that last point – which fuel is used, and how carbon intensive it is. But it
will be beyond 2030 before low-carbon fuels, like hydrogen or ammonia, grow
past a single-digit percentage of all shipping fuel used. This is a problem: if
we are to meet the Paris Climate Agreement goals, emissions need to see
dramatic reductions in the short term.
That means we need to think about the wide range of other
ways to cut shipping emissions in the coming decade. Here are ten areas to look
at:
1. Reduce the amount of fuel needed for shipping by
transporting less stuff…
In a world of finite resources, we need to think critically
about consuming less – for example, whether we need to import containers of
garden gnomes from China to the UK, or whether high street clothes retailers
should continue to prioritise fast fashion models where clothes are shipped
halfway around the world yet only designed to last for several uses.
2. …over shorter distances…
It’s possible that long distance transport might become less
necessary in the future, as the rise of 3D printing could see goods printed
locally and on demand. The new generation of shipping fuels could also be produced
nearer to where they’re needed, so they only have to be transported by ship
over hundreds, rather than thousands of miles.
3. …at slower speeds.
The faster ships move, the more energy they need. The bottom
line is that going slower is one of the most effective and immediate ways to
cut ships’ fuel use. This can happen naturally due to high fuel prices, but
locking in these benefits needs action from the IMO, such as regulation on ship
speed limits.
4. Retrofit ships.
There are multiple ways to retrofit ships so they use less
fuel, like upgrading ship propellers and hulls to improve fuel efficiency.
5. Make use of the wind…
Spinning cylinders called Flettner rotors and huge kite
sails are just two technologies that harness the power of the wind to help
propel vessels. This can cut fuel consumption by 10 percent. Coupling this with
computer programs that model wind speed and direction allows ships to optimise
their routes, saving ships a further 10 percent of fuel.
6. …and shore power.
Ships can use less fuel when in port by switching off their
engines and connecting to local electricity grids instead. This technique,
which also reduces air pollution in coastal cities, is called “shore-power”.
Norway, the USA and China lead in implementing shore-power thanks to government
support.
7. Carbon accounting
Many alternative fuels produce low levels of carbon dioxide
when burned. But the emissions arising from their production need to be
properly accounted for, or we’ll just be shifting pollution from one source to
another. Hydrogen can, for example, be produced in different ways that lead to
very high or very low carbon emissions.
8. Carbon taxes
Attempts to cut carbon in the shipping industry tend to
flounder because standard marine fuels like diesel are globally untaxed and
therefore cheap. It’s time for the IMO to levy charges on carbon pollution, to
allow alternative fuels to compete with traditional carbon-based ones. Revenues
from this can fund research and development into new fuels, and support
developing nations to decarbonise their shipping sectors.
9. Green policymaking
The UK could prioritize building zero-emission vessels in
its forthcoming National Shipbuilding Strategy, and run more innovative
contests like the already oversubscribed Clean Maritime Demonstration
Competition to provide greater support for greener shipping tech.
10. Stronger framework
All of the above methods need to operate within a clear
framework for reducing overall shipping emissions if the sector is to play its
part in meeting the goals of the Paris climate agreement. The IMO needs to
commit to more stringent climate targets to deliver major reductions in the
coming decades. In shipping, as in every sector, we need to use every way we
can to cut emissions as fast as possible.