As some look to harness the wind to power commercial ships via windsails, Vindskip is looking to launch a car carrier using the wind as power assistance. The hybrid Vindskip is in a class of its own.
This revolutionary design would use its hull – described by its Norwegian designer, Terje Lade, as being shaped like a symmetrical hydrofoil – and the wind to lift the vessel, thereby cutting its fuel consumption by 60% compared with conventional 6,200-vehicle-capacity car carriers.
Vindskip could operate through the Panama Canal’s newly expanded locks and, like Blue Technology’s Liberty, would have outriggers for stability. However, Vindskip would use the ship’s shape to develop wind-assisted power that would add to its liquefied natural gas (LNG)-powered main engines.
As the vessel gains speed, the wind flow over the hull would create a pull to assist the vessel on its journey, while the LNG propulsion would maintain the speed at a constant level even if the wind speed varies. Using computational fluid dynamics, the hull design has been optimised to offer pull for the vessel from an angle of 18° through to 180° and has minimised the leeway and rudder angles to further reduce drag.
Main engine propulsion would be provided by a Rolls-Royce system, which includes an LNG-fuelled main engine and two auxiliary engines, one powered by LNG and one capable of operating on either LNG or a bio-fuel. Shaft generators and a Rolls-Royce-designed propeller, coupled with two 700 m3 LNG fuel tanks, offer a range of propulsion options.
The Rolls-Royce system would allow up to 2,000 kW of electrical power from the auxiliary engines to be supplied to the propeller without the main engine engaged, offering either slow steaming and manouevring or propulsion assist in favourable wind conditions.
Moreover, a computer programme, developed by Fraunhofer CML, would calculate the optimum route for the vessel’s journey by either prioritising economy, one with favourable winds, or the expected time of arrival to allow for greater usage of LNG. According to Lade, the dynamics for powering the vessel and its weather routing system would achieve fuel savings of up to 60%.
Lade said the cost of transporting a car from Europe to the United States would be “about 50% lower than a standard car carrier”, at about USD215/car, with little in the way of SOx emissions and very low NOx pollution. Carbon emissions are calculated at 11 kg per car per 1,000 km, with an additional 0.11 kg per car to account for methane slip.
In total, Lade calculated that operating the 7,200 kW engine at a 64% maximum continuous rate would consume 150 g of LNG/kWh, emitting 1.25 g/kWh of NOx, 0.01 g/kWh of SOx, and 380 g/kWh of CO2, with a further 3.8 g/kWh attributable to methane slip. This is not negligible as LNG is calculated at 21 times more potent as a greenhouse gas (GHG) than carbon. The total GHG equivalent emissions are calculated at 14.72 g/kWh/car for every 1,000 miles.
By comparison, Lade said Vindskip’s CO2 emissions, calculated on a tonne-kilometre basis, would total 10.5 g of CO2/tkm compared with Toyota Logistics, which calculates its operations as emitting 109.6 g of CO2/tkm.
A European yard has already signed on to build the vessel, and negotiations for an order from a European car manufacturer are also under way, added Lade. However, as the vessel has a revolutionary shape and the detail of the hull under the water is different from conventional vessels, “we have to develop a building method. The ship is not ordinary so we have to find the right way to build it,” Lade said.
Lade admitted, “The biggest cost will be the capital expenses. It is more expensive [to build] than a standard car carrier as the LNG systems are more expensive.” He estimated that the extra cost associated with building Vindskip is about USD50 million, adding that the 2020 sulphur regulation will be a game changer.
It is generally accepted that operating a conventional vessel will become more expensive after the sulphur regulation comes into force in January 2020, either through the cost of installing and operating scrubbers or through the higher price of distillate fuel.
“Ordinary car carriers are optimised for a single speed, but these only operate at their design speed for 5% of the time, so they are not economical if they need to change to slow steaming, whereas Vindskip is economical at any speed,” concluded Lade.
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