Project Vindskip the Fuel Efficient Ship

The Norwegian designers at Lade AS, have come up with a new concept for a partly wind-powered merchant ship the Vindskip (Windship). According to Lade AS the ship’s design can cut fuel use by 60% and carbon emissions by up to 80%.

Design

The design concept is based to the “lifting body” principle of aircraft design, this is that the shape of the main hull is used to generate a positive lift as the engine pushes the aircraft forward. In the case of the Vindskip, the hull is shaped similar to a giant sail and according to Lade AS this generates a forward thrust towards the apparent wind.

Vindskip having a hull shaped like a symmetrical air foil going in the relative wind, will generate an aerodynamic lift giving a pull in the ships direction, within an angular sector of the course. This is Vindskip’s Wind Power System. The relative wind, measured on board a ship, is given by the ships course and speed and the direction and strength of the True Wind.

With an LNG-electric propulsion system as well, starting the ship from zero up to the desired speed, the aerodynamic lift now generated can be exploited to generate pull and thus saving fuel: Forming a dynamic system that maintains a constant speed of the ship. Ship types that are particularly relevant to the Vindskip design are

RoRo
RoPax
PCTC
Passenger ships
Container ships

The design of Vindsjip has already received several international patents.

The Dynamic Propulsion System

The Wind Power System will give a varying positive contribution to the propulsion of the ship in period of time. Using computerized weighting of meteorological data, a computer program will calculate the best sailing route to exploit the available wind energy potential.

The ship will be also equipped with a Cruise Control in order to balance the LNG-electric propulsion system so that it will work as a dynamic entity together with the Wind Power System. Keeping a constant speed of the ship. By firstly adjust the pitch on propeller and then the rpm, it will make it possible to obtain a lower fuel consumption.

True wind is the wind measured on board a stationary ship. When the ship starts moving, the so-called relative wind is being generated: The apparent wind measured on board a ship. The Wind Power System of Vindskip utilizes this Apparent Wind and generates a positive force in the longitudinal direction of the ship as a function of the angle of attack.

LNG propulsion system

Rolls-Royce has devised a LNG propulsion system to meet the Vindskip’s requirements that retains a high level of efficiency over a wide range of power outputs, minimising greenhouse gas and NOX emissions, and eliminating the sulphur emissions that are a problem with today’s conventional PCTCs burning residual fuel.

Liquefied natural gas (LNG) is the fuel, contained in two tanks holding sufficient for about 70 days of steaming at 17 knots. Two Bergen B35:40L8P lean burn gas engines provide the main propulsion power. Each develops 3,500kW at 750rpm and can be coupled to a twin input single output gearbox. A long propeller shaft connects the gearbox to the CP propeller, which is integrated into a Promas propulsion system comprising propeller, hubcap, rudder bulb and a twisted leading edge spade rudder. Promas recovers energy normally lost in propeller slipstream swirl and converts into forward thrust, increasing the total efficiency. Two shaft generators are also connected to the gearbox as part of the Rolls-Royce HSG system. They can function as generators able to run at variable speeds while supplying electricity at constant frequency to the ship’s main switchboard. Alternatively they can operate as motors fed with current from the C26:33L6AG gas fuelled auxiliary generator set for low speed steaming. At sea Vindskip’s electrical loads would normally be supplied by the main engines through the HSG system, and in port by the genset that can also feed the large fans that ventilate the car decks to remove fumes during loading and discharging of the cars under their own power.

If the all the above are proved also in practive the Lade AS’ fuel-efficient ship concept would be a step forward in revolutionizing the shipping industry and thus reducing considerably fossil fuel use.