https://www.moneyweb.co.za/news/industry/how-the-cargo-ship-industry-is-cleaning-up-its-filthy-act/
[No mention of Flettner rotors. In think hydrogen can be ruled out of
vessels making trans-ocean crossings due to storage space required and
lack of fueling capacity and refueling infrastructure.]
How the cargo ship industry is cleaning up its filthy act
Liquefied natural gas is another option, but the cleaner fuel requires
whole new engines.
Kyunghee Park and Jason Clenfield, Bloomberg / 19 January 2019 00:55
Air pollution from cars and factories has been regulated in much of the
world since the 1970s. When it comes to the smoke-belching ships that
carry global trade, the rules have been a lot looser.
Big changes start next January, though, when long-debated standards from
the International Maritime Organisation mandate steep cuts of sulfur
emissions associated with respiratory disease and acid rain. Much
tougher rules are supposed to take effect in 2050, when the IMO will
require ships also reduce carbon dioxide emissions by at least half.
By itself, next year’s cap could prevent 150 000 premature deaths and
millions of childhood asthma cases each year, according to research
published in the journal Nature. It will also cost tens of billions of
dollars for an industry that’s dragged its feet on the environment.
Necessity being the mother of invention, some of the world’s most
conservative companies are starting to experiment with cleaner fuels and
cutting-edge technologies. Here some of the brave, new ideas in green
shipping:
Sails!
AP Moller-Maersk A/S is considering using a modern version of the
old-fashioned sail to help power its ships. The devices, which are being
tested on one of Maersk’s giant tankers, look more like huge marble
columns than anything you’d expect to see on a traditional yacht.
Together, the two 10-story-tall cylinders can harness enough wind to
replace 20% of the ship’s fossil fuels, according to Norsepower Oy,
which makes them.
Eco Marine Power, a startup based in Japan, has designed another sail
this one with solar panels in its body. Chief technology officer Greg
Atkinson says the firm is in talks with one of the world’s biggest
shippers to test the device this year.
Underbelly bubbles
Just as carmakers fine-tune the aerodynamics of their vehicles to get
better gas mileage, shipbuilders also try to reduce the friction between
a vessel’s body and the water. Optimising hull shape is one strategy.
Another, being tried by firms including Samsung Heavy Industries and
Mitsubishi Heavy Industries, is streaming bubbles out of tiny holes in a
ship’s underbelly, as a lubricant, to help it slice more cleanly through
the water. It’s a little like floating on a carpet of air.
Samsung says it’s already installing the system on one vessel being
built for Mediterranean Shipping Co. and has received two other orders.
The tech can cut fuel consumption by 4 or 5%, according to the company.
Robot cleaners
Since the earliest days of sea voyages, sailors have been troubled by
grasses, barnacles and other organisms that grow on hulls. All the
biggest cargo lines are now using submarine robots to strip away such
debris and improve fuel efficiency.
One device, developed by a Japanese startup called Hullbot, looks like a
propeller-powered go-cart with nylon brushes and a vacuum on its belly.
Thrusters on its back keep it pinned to the vessel’s hull. No divers are
needed, but the machine still requires a human operator to guide it by
remote control.
Hydrogen fuel
The world’s biggest shipbuilder, Hyundai Heavy Industries, last year
announced it’s developing hydrogen-fueled engines for its massive
vessels. The tech is in its infancy, but some proof of concept may come
later this year when a small ship being billed as the first fuel-cell
passenger ferry, the Water-Go-Round, begins operating on San Francisco
Bay. Hydrogen-based ferry systems are also planned in Norway and
Scotland’s remote Orkney islands.
Battery boats
The challenges faced by electric cars, with their limited driving
ranges, are even more daunting when it comes to ocean-going ships, which
can weigh 600 000 tons and must often travel thousands of miles.
Shipbuilders are experimenting with smaller river vessels and other
craft that stay near shore.
In Norway, where the government wants two-thirds of all ferries carrying
passengers and cars along its Atlantic coast to be electrified by 2030,
Kongsberg Gruppen ASA is offering battery-powered ship engines and
developing a short-haul electric container vessel.
A Chinese-built ship launched in 2017 on the Pearl River, near Hong
Kong, was the first fully-electric cargo carrier of any size, according
to the China State Shipbuilding Corp. The vessel is emissions-free, but
even with batteries sufficient to power three dozen Tesla sedans, the 2
000-ton ship can only travel about 50 miles without recharging, says the
China News Service.
Exhaust scrubbers
Within the next few years, some 10 to 15% of ships are projected to
install scrubber systems, like the ones used on factory chimneys, to
capture sulfur and fine particulate emissions before they escape exhaust
funnels.
Makers of the devices, such as Finland’s Wartsila OYJ and Sweden’s Alfa
Laval AB, say there’s already a big backlog of orders, so many ships
won’t be outfitted in time for the 2020 rule change. Bloomberg NEF
estimates some 4 800 vessels will be scrubber-equipped by 2025.
Fossil fuel switch
The most immediate and consequential change is the most mundane:
switching to lighter marine gas oil, which is something closer to the
diesel used for highway trucks. It’s still a fossil fuel, but less
polluting because it’s been more thoroughly refined.
Marine gas oil is already used in Emission Control Areas, like the ones
around Europe’s coasts, but using it full time in order to meet the new
emissions rules will cost shipping companies an extra $40 billion to $60
billion annually, according to Goldman Sachs Group and researcher Wood
Mackenzie.
Liquefied natural gas is another option, but the cleaner fuel requires
whole new engines and port facilities to store it. In 2016, Nippon Yusen
KK launched the world’s first LNG-powered car carrier and last October a
Russian super tanker the length of several football fields crossed the
Baltic Sea, running on the condensed gas.