Propulsion

Will wind-assisted propulsion blow the maritime industry away?

A partnership between NAPA and C-Job Naval Architects is studying the applications of wind-assisted propulsion using voyage optimisation software, hoping to ultimately drive the industry away from polluting fuels and help it prepare for the IMO’s ever-stricter requirements. Adele Berti finds out more.

Image: Maersk Tankers

Call it a sign of

the industry’s nostalgic attachment to its origins, or more simply the answer that’s been under everybody’s nose for far too long, but it seems like the age of wind-powered ships is back for good, and it might well be a key element in the fight against climate change.

The only propulsion method for ships between the 19th and early 20th century, wind propulsion relies on sails or similar wind-powered devices like rotor sails, with its current, modernised version reportedly leading to substantial fuel and costs savings.

That is according to recent research by maritime software, services and data analysis provider Naval Architectural Package (NAPA) and C-Job Naval Architects, whose joint work has been focusing on optimising prevailing wind patterns and encouraging the industry to get on-board with wind-assisted propulsion.

Over the past few years, this technology has also been tested by the likes of Viking Line, Bore, and Maersk Tankers. In particular, promising results recently came from Maersk, who, in autumn 2019, revealed having achieved an 8.2% reduction in fuel consumption in its 12-month trial of rotor sails aboard Maersk Pelican.

Recent findings from NAPA and C-Job’s studies have also confirmed the potential of rotor sails, which can help save up to 20% of fuel on deep sea routes. Their research is being conducted with the support of NAPA’s weather routing software, Voyage Optimisation, which “combines historical weather data and current weather predictions with a vessel-specific ship performance model”.

As more troubled waters await the industry in the years to come, the two companies share their insights on wind-assisted propulsion and its environmental benefits.

A look at the technology

As Claus Stigler, senior software developer at NAPA Shipping Solutions explains, the starting point is the company’s own Voyage Optimisation software, which uses artificial intelligence to calculate a preferable voyage route for a particular vessel and the fuel savings it would bring. “The tool is based on a number of very explicit inputs,” he says, “like a voyage departing, for example, from Rotterdam to Houston, starting in three hours, lasting for two weeks, with a given particular ship.”

Whilst the technology can be used for different applications – and is currently being rolled out in its browser version for remote use – it is also helping optimise prevailing wind patterns for wind-assisted propulsion.

This was the driver behind NAPA’s collaboration with C-Job. Robin Berendschot, a naval architect at C-Job, explains that the software can be used to simulate the effects of wind-assisted propulsion in shipping, and therefore work out the most advantageous routes for a company.

In any place on earth where there is wind, you can use wind-assistance propulsion to save fuel

In some cases, these will be those old trade routes that were once popular among sailors. “If you're sailing on traditional sailing routes, using global trade winds, those routes are the most favourable to use because they have the most wind going in the right direction,” explains Berendschot. “There are predominantly strong winds in some specific directions, and those routes are theoretically the best routes for wind-assisted propulsion. But in any place on earth where there is wind, you can use wind-assistance propulsion to save fuel.”

According to Stigler, things have radically changed since sailing routes were popular: “[Back then] the paradigm was more following the rain cycles and avoid storms, but now what should be, instead, the case is having an optimal route that is both the safest and most fuel-efficient,” he says.

Finding that route requires a set of data and knowledge which go beyond the assumption that a certain current pushes in a specific direction. Instead, weather factors are now only a part of the job, as they need to be combined with engine load input, the model of the vessel and prevailing ocean currents. “That's why in our voyage optimisation software, there is a multiple chart-based derived route network thanks to which we get frequent updates,” he concludes.

Wind turbine parts being loaded onto supply vessel.

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Helping the industry shift towards sustainable shipping

Reduced fuel consumption is not only positive for a company’s finances but also, as Stigler claims, a key factor towards boosting the industry’s environmental credentials.

“At the most recent conference I attended,” says Stigler, “it seemed very obvious from the companies presenting there – as well as in general – that the market has just recognised that there are massive improvements necessary for the industry in order to tackle pollution.”

Indeed, January 2020 has marked the start of the long-awaited sulphur cap rollout by the International Maritime Organization (IMO), which represented the first of the industry’s three long-term commitments to decarbonise shipping and making it become more environmentally conscious.

The industry has recognised that partnerships are the most essential tools here

Most of all, the sector is bracing itself to pursue the IMO’s future targets of achieving a 42% CO2 reduction by 2030 and 50% greenhouse gas cut by 2050, an effort that Stigler says can only be successful if everyone works together. “The industry has recognised that partnerships are the most essential tools here, as a single company just cannot alone make the changes necessary to reach these ambitious IMO requirements.”

This, he continues, is the reason behind NAPA’s decision to switch its Voyage Optimisation technology from installer to browser, extending its use from one single ship to an entire fleet. Its also why NAPA decided to partner with C-Jobs, as well as with different traffic platforms, to carry out its analysis.

“These partnerships lead to increasing the number of potential users and the number of potential savings based on the world fleet, all in order to meet a very strict but important set of requirements.”