A few years ago, I sailed on a ship
that comes from an earlier era,
when moving goods by sea
didn't mean polluting the planet.
Our voyage to the Caribbean
was eye-opening,
and not just because I learned
that apparently, I’m incurably seasick.
(Laughter)
I also saw what it's like
when you take away the diesel fumes
and the black smoke
that spew from today's
freighters and ports.
Instead, our vessel smelled
like fresh sea breeze
and the bags of cardamom we carried
and all that camomile tea I was chugging.
Nearly every modern cargo ship
relies on highly polluting fossil fuels.
Fortunately, there's a way
to clean up the industry,
beyond just reviving
old-fashioned sailing ships,
and it's ...
green ammonia.
If you know anything about ammonia,
it's probably that it's stinky,
it's toxic, it's potentially explosive.
So it's a great place to start, right?
Ammonia is mainly used today
to make chemicals and fertilizers.
But for many reasons,
industry experts are convinced
that ammonia could be a game-changing way
to drive giant cargo ships,
and that it could be used safely
and be cost-competitive.
Tens of thousands of freighters
crisscross the oceans every day,
bringing the food we eat,
the clothes we wear, the cars we drive.
Container ships alone
carry some four trillion dollars
worth of goods by sea every year.
That's roughly the GDP of Germany.
At the same time,
the shipping industry
contributes a significant share
of the world's annual
greenhouse gas emissions.
If shipping were a country,
it'd be the sixth largest emitter of CO2,
trailing just behind Japan.
And as world economies grow
and populations rise,
shipping's emissions are expected to soar,
unless the industry
charts a cleaner course.
Green ammonia really first came
to my attention in 2017,
at the UN Climate Change Conference
in Bonn, Germany.
At the panel I attended,
ammonia seemed kind of like an aside,
or something we should be keeping tabs on.
Since then, the industry
has really coalesced around ammonia
as the next dominant shipping fuel.
Chemical companies and investors
are spending millions of dollars
to build green ammonia plants,
and shipbuilders and manufacturers
are busy developing
the necessary technology.
The first ammonia-powered ships
are just around the corner.
So what's so special
about this pungent gas?
Well, to start, ammonia doesn't contain
any carbon molecules,
so it doesn't create carbon dioxide
when used as fuel.
Instead, it contains one part nitrogen --
which is the main component of air --
and three parts hydrogen,
which is a building block of water.
It's possible to make ammonia
without using any fossil fuels.
That's what makes it "green" ammonia.
Think of it like this:
instead of the oil wells
and petroleum refineries
that make today's dirty diesel fuels,
picture solar panels or wind turbines
or hydropower plants.
Renewable electricity is the foundation
of this whole ammonia-making ordeal.
We can start with electrolysis,
which uses electricity to split water
into hydrogen and oxygen.
Then, renewables can power the process
that separates nitrogen from air.
And so with our hydrogen and nitrogen,
we can combine the two
in an industrial process
at high temperatures
to make NH3 -- ammonia.
Now, if you want to use
this ammonia to power
your thousand-foot-long freighter,
you have two options.
The first is an internal
combustion engine,
so similar to how diesel
is used in ships today
but with certain modifications.
Experts think that the first vessels
to use ammonia in their engines
will be chemical tankers,
because they already carry it
in their cargo holds.
So they'll be like the early adopters.
The next options is to use a fuel cell.
Fuel cells create electricity
through a chemical reaction,
and that's what drives the ship's motors
and turns the propellers.
In Norway, work is underway
to launch the world's first
ammonia-fuel-cell ship
in just a few years' time.
So we can make green ammonia,
and we can use it
in fuel cells or engines.
The final piece of the ammonia
puzzle is the infrastructure:
the storage facilities, the pipelines,
the distribution networks --
everything that's needed to ensure
a ship can fill its tanks
anywhere in the world.
And none of this is particularly novel,
because we already have infrastructure
for the chemical
and fertilizer industries.
Now it just needs to be built near ports,
and at a global scale --
and with great caution.
So what's needed
to take ammonia mainstream?
We can draw a rough parallel
to the rise of electric cars.
A decade ago,
about 17,000 EVs
were on the roads worldwide.
Then, more and more countries
adopted policies,
encouraging people to buy EVs,
supporting manufacturers
and to build up charging infrastructure.
And as sales climbed
and production boomed,
the cost of batteries
and other components plummeted,
making it easier for more people
to afford electric cars.
So now, instead of 17,000 EVs,
it's more like 10 million,
and green ammonia
could follow a similar path
in the shipping industry.
Policies to curb emissions
and incentivize green investments
could spur a shift away from fossil fuels.
And as ammonia catches on,
fuel prices and technology costs
could decline in step,
enabling more ship operators
to make the switch.
And while all of that is happening,
a much bigger story will be playing out
on the global scale:
the rising development and plunging costs
of renewable energy supplies.
Giant offshore wind farms,
sprawling solar arrays
and other technologies
could provide the electrons
needed to make that green ammonia.
Green ammonia might be
the main fuel source
on future cargo ships,
but it doesn’t have to be
the only clean technology onboard.
Ships will likely use
a combination of tools.
Batteries can already power
the lights and equipment on giant ships,
and certainly, smaller vessels
can be fully battery-powered today.
Design fixes, like supersleek hulls
and dolphin-like flippers,
can improve ships' efficiency.
And another technology
that's quickly gaining traction
is called "wind-assisted propulsion,"
which puts a modern twist
on an old idea of harnessing wind.
One cargo ship I sailed on
in the North Sea
uses devices called "rotor sails."
These are 60-foot-tall tubes
that spin around
like hyperactive barber's poles,
which produces a forward thrust
and reduces demand on the diesel engines.
It's really exciting to see
these things whip around,
but it's funny how almost blasé
the crew was about the whole thing.
They push a button,
the tubes swirl to life,
the ships saves fuel,
and they can all carry on
with their normal tasks,
as we sailed from Rotterdam
to this industrial eyesore
in northern England,
and back again.
Meanwhile, of course,
I spent my time admiring the sails,
and then curling up in the fetal position
as the sea knocked our ship around.
The maritime industry
is at a pivotal moment
in its long and storied history.
Over the last few centuries,
fossil fuels have powered the freighters
that have transformed global trade,
connecting cotton fields
to far-flung garment factories
and bringing blueberries
from one side of the equator to the other.
Coal-powered steamships made it possible
to travel farther and faster,
and diesel engines
took this into overdrive.
What began in the early 20th century
as a humble canal boat
puttering along with this tiny engine
has since become giant container ships
that stretch as long
as skyscrapers stand tall.
We know that to keep the planet
from warming further,
we must completely transform the way
that we power our homes, our cars
and the freighters that bring us
all our precious stuff.
The shipping industry
must join the rest of the world
in addressing climate change,
and it could do that
with the help of green ammonia.
Thank you so much.
(Applause)