Sails make a comeback as shipping heads for complete decarbonisation by 2035
by Eric Marx, February 19, 2019
Last year’s ITF report asserts that an almost complete decarbonisation of shipping could be achieved by 2035 using currently known technologies. Whilst LNG is gaining momentum, hydrogen, ammonia and biofuels could be more sustainable means of delivering much of the required reductions, complemented by a mix of electronic propulsion and wind assistance. The message, according to independent journalist Eric Marx, is “Hold on. There’s a decade of experimentation ahead”. He counsels against becoming locked-in to any one solution with so many alternatives about to come to market. One, the power of the wind, is already making waves.
The commercialisation of various wind propulsion technologies, underway in Europe since 2018, is set to take off this year as looming carbon targets generate renewed interest in one of the world’s oldest means of travel – catching and harnessing the wind.
The future of shipping could see automated kites deployed from 40-foot containers. Fixed wing sails hoisted atop 35-meter-tall rigs are also being taken seriously, as is the recent deployment of Flettner rotors on a Greek-owned dry bulk carrier, a Scandinavian passenger ferry and the Maersk Pelican, a 100,000 ton tanker vessel.
Flettner rotors were first trialled in the 1920s, but only now have been brought into commercial use with the advent of modern composite materials and software automation, explained Jarkko Väinämö, the CTO of Finland’s Norsepower, which added its Rotor Sail Solution technology to the Pelican in August, a world’s first for a tanker vessel.
It took all of 24 hours to install the two 30-meter-high spinning cylinders, which don’t resemble sails but which create a similar vertical force that can be used as an “auxiliary system” to a ship’s main engines.
“Without any integration, we can bring from five to 20 percent fuel consumption savings,” said Väinämö.
Integration in this case would include new-build ships that take into account wind propulsion together with innovative hull designs, and the use of alternative fuels such as hydrogen, ammonia, LNG and second- and third-generation biofuels, alongside engines powered by electricity or fuel-cell technology.
Each has its drawbacks and advantages. There’s no single solution, warn experts, and yet there’s much that can be done quickly by retrofitting existing ships.
Wind propulsion took on greater urgency after the International Maritime Organization (IMO) reached an agreement in April to slash emissions by 50 percent by 2050.
This helped prod Maersk, the world’s largest container shipping company, to announce in December a pledge to cut its emissions to zero by 2050 – going beyond the IMO targets, but in line with a report issued by the International Transport Forum (ITF), an intergovernmental organisation with 59 member countries which acts as a think tank for transport policy.
“We will have to abandon fossil fuels,” Soren Toft, Maersk’s chief operating officer, told the Financial Times. “We will have to find a different type of fuel or a different way to power our assets. This is not just another cost-cutting exercise. It’s far from that. It’s an existential exercise, where we as a company need to set ourselves apart.”
For Maersk to meet its targets, carbon-neutral vessels will have to be sailing by the early 2030s, say experts.
As well as all the new fuelling options, The ITF report authors also point to a list of efficiency measures, such as “slow steaming”, which could yield a substantial part of the needed emission reductions. Over the past two years, for example, Maersk has discovered it could cut fuel use by as much as 30 percent by slowing down ship speed.
LNG-fuelled hybrid could be dead-end
Why then commit to LNG-powered vessels if zero-carbon shipping is just on the horizon?
“LNG can reduce air pollutants significantly, but it’s carbon footprint is more or less the same as with Diesel/HFO [residual fuel oil],” e-mailed Dietmar Oeliger, head of transport policy at NABU, a German environmental group that monitors shipping.
Some LNG ships claim a reduction in CO2 emissions of 15 percent, though that depends crucially on keeping leakage of the greenhouse gas methane to a minimum in ships and bunkers.
“If we are serious about decarbonisation mid-century, that [LNG] is wasted money,” Dr. Lucy Gilliam, T&E
Investing massively in LNG infrastructure might cause lock-in effects, said Dr. Lucy Gilliam, an aviation and shipping expert with Transport & Environment, which campaigns for cleaner transport in Europe. “Why not instead switch to diesel, install emission abatement technology, and wait for a decarbonized fuel?”
That’s the course many are now taking – in light of a global sulphur cap due to take effect next year and owing to the high cost of new LNG engines.
“If we are serious about decarbonisation mid-century, that [LNG] is wasted money,” added Gilliam.
Diesel engine manufacturer Man Energy Solutions is one of those in the LNG camp.
“Switching ship engines to LNG as a fuel not only reduces harmful emissions at a first step, but also enables the engines to use fully decarbonized e-fuels as soon as these are available on a large scale at a later time,” e-mailed Jan Hoppe, a Man spokesperson.
E-fuels are the result of transforming electrical energy from renewables into CO2-neutral synthetic fuels.
But backing e-fuels – by, for example, producing synthetic methane or synthetic diesel through electrolysis from water using cheap renewable energy – would require a massive build-up in solar and wind deployment, noted Gilliam. Moreover, it would necessitate advanced isotope analysis in order to ensure proper regulatory oversight.
“It’s useful to actually reduce the amount of fuel you need to burn,” she added. “We are very much saying we need to do both – alternative fuels and new propulsion systems.”
Transport & Environment, which represents the environmental community on matters before the European Union in Brussels, favours hydrogen made from natural gas in land-based industrial processes. Ammonia is also top on an efficiency basis and is easier to transport and store, though large scale ammonia usage does present health and safety issues that still need to be worked out.
Electric power with battery storage could also play a role, especially on short haul, regularly scheduled ferry passage. Norway’s parliament certainly thinks so – having adopted a resolution last April that would halt emissions from cruise ships and ferries in the Norwegian world heritage fjords “as soon as technically possible and no later than 2026.”
The assumption is that the fjords will only service electric ships in just 8 years time, bringing about what would be the first zero emissions zone at sea.
Wind sails ahead
As for wind propulsion, shipping companies are waiting to see what can actually be delivered.
A total of 14 Flettner rotors are currently sailing on six commercial vessels, according to Gavin Allwright, secretary of the International Windship Association (IWSA), a trade body that represents the wind propulsion sector.
Generally, retrofit wind propulsion rigs can deliver between five to 20 percent fuel savings, with an upwards potential of 30 percent, and 30 percent and above for new build optimized systems, meaning a renewable energy source with free and abundant delivery at the point of use, said Allwright.
In addition to Norsepower, the British company Anemoi Marine Technologies has four rotors spinning on the MV Afros, a 64,000 ton bulk carrier operating in the Pacific. Magnus, a US company, has developed a retractable rotor that acts like a telescope, while the interregional project fund Marigreen has seen German and Dutch partners recently launch a commercial vessel in the North Sea.
The sector is also expecting announcements this year from other hard and soft sail developers.
The next step is to establish regional hubs, said Allwright, in order to bring down costs and bring further integration to the sector.
Yet, all eyes are on Flettner rotors, for now at least, given the recent announcements from Maersk and Viking.
Norsepower alone has another six to seven rotor sails launching in 2019, with its first new-build project in hand and set for installation in 2020, according to Väinämö. In five years the company forecasts annual revenue exceeding €100 million, a projection that would see upwards of 60 to 70 installations a year.
“That’s where the market is currently focused,” said Allwright. “Rotor sails are on the water and have opened the market.”
A vision for shipping’s net zero-emissions future is rapidly coming into focus. The industry should hold off from making any sudden moves as we enter a decade of experimentation which will reveal the optimum cost/benefit result using the best combination of all the solutions on offer.