Slow steam ahead!

Sometimes less speed can be king, too. Wärtsilä's Busser project introduces Ultra Slow Steaming. Yeah, that's right. Ultra Slow.

Moving goods from point A to point B as fast as you possibly can is the drill in today's logistics. However, out at sea, a rather contradictory method has been in use for some years now. In slow steaming, you deliberately slow down the speed of a vessel in order to lower costs by reducing fuel consumption. Even in a weak freight market, this approach allows you to stay profitable, by absorbing excess tonnage and cutting down on fuel consumption and bunker bills as you slowly steam along.

Teus van Beek, General Manager for Wärtsilä’s Market Development & Innovation, says that recent trends in shipping point towards slower, larger and simpler operations. And as ships take longer to reach their eventual ports, a big crew on the payroll translates to higher labour costs. According to Wärtsilä, moving towards unmanned ships could well be the way of the future – but only under certain circumstances.

“Decreasing crew cost by reducing headcount only makes sense in a situation where speed – time used to make the voyage – is not a factor, meaning that the speed is low,” van Beek says.

However, fuel still accounts for the majority of the ships' operating cost. As only about 25% of the energy contained in the fuel is used today, ship efficiency, along with speed reduction, is key when it comes to keeping costs down.

Size Does Matter

Many people in the marine industry believe that autonomous shipping is the answer to the cost reduction scenarios of the future. Senior Development Manager Henning von Wedel observes that there is, however, a strong trend that counteracts the autonomous concept: the sheer size of the vessels is increasing.

“We see that not only in the containership market, but also for liquid and bulk cargo. Cruise ships are also getting bigger and bigger.”

“The challenge is – beyond the economy of size – to convince our customers that the issue is more complex and requires looking at integrated concepts, which include shipbuilding and operation cost for the vessels,” von Wedel says, while pointing out that taking only crew costs into consideration here would offer a very short-sighted perspective on the matter.

Hi-Tech Edge

As a global marine systems supplier, Wärtsilä focuses on concepts where the technology development helps customers reduce costs.

“This involves efficient shipbuilding processes, new materials, efficient propulsion, enhanced automation and, going along with all this, operations simplification,” lists von Wedel.

The related technology areas for Wärtsilä are quite numerous, too: integrated automation, smart energy management, big data and propulsion and powering, as well as advanced shipbuilding materials and processes, autonomous systems, renewable energy integration and communication. 

Going Ultra 

Wärtsilä’s concept of ‘Ultra Slow Steaming’ relies on big vessels bringing economy of scale and tried-and-true route plans that may be long but steer clear of unexpected weather conditions.

According to Teus van Beek, Ultra Slow Steaming is a solid option when no cooling or other input is required to keep the cargo in good condition, and the cargo itself does not need much attention. Furthermore, the vessel in question is not required to be particularly hi-tech.

Henning von Wedel explains that Wärtsilä is looking into unmanned Ultra Slow Steaming, since cost reduction is exactly what the customers want. Nevertheless, there are many factors at play.

“One of the factors is the vessel's operating cost, and another one is the crew cost. The slower you go, the lower the operational cost, and, opposed to that, the crew cost increases with lower speed,” von Wedel says, adding that there are also additional cost factors – such as the financial cost for the cargo and freight rates – that also rise as speed goes down.

Complex Puzzle

And the desired result is? For each and every case, there is an optimum speed that depends on the type of vessel or cargo, the route and the general ambient conditions. In order to thoroughly investigate these matters, Wärtsilä launched a project called BUSSER – Ultra Slow Steaming Bulker Concept – in June 2015.

So far, the BUSSER team has decided on the optimal vessel type.

“We have selected bulker vessels, which are under heavy pressure by the markets, for our evaluation purposes. For the example case, the optimum speed is between 6 and 8 knots, while conventional bulkers operate at about 12 to 15 knots,” von Wedel says. 

“The next step is developing a demonstrator project together with one of our customers.”

Subsequently, other market segments, such as ferries or cruise ships, also will be targeted.

Wave of the Future

The guiding vision for BUSSER aims for a future when a ship has no human crewmembers and uses no fuel. In this brave new scenario, super slow steaming minimizes fuel cost.

Human error is eliminated from the picture, and the vessel will feature optimized hydrodynamics, wind and conventional propulsion, remote control, full automation and maintenance on demand. Henning von Wedel and Teus van Beek acknowledge that there’s still a lot of work ahead before the goal comes to life.

“There is always a compromise between what is doable, affordable and what makes sense in the changing conditions of the markets. “Future trends point in the direction of renewable power supply and reduction of crew,” von Wedel concludes.


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