Designs for First Methanol-Fueled Crew Transfer Vessel

design for methanol-fueled CTV
(Robert Allen)

Published Oct 6, 2021 7:06 PM by The Maritime Executive

Canadian naval architects Robert Allan have developed designs for its first methanol-fueled crew transfer vessel. The project supported by the Carbon Trust, UK and the Offshore Wind Accelerator program, offers both significant cost advantages for offshore operators as well as providing a path toward eliminating carbon emissions from the sector.

“The possibility of using green methanol marks a shift from the current linear fuel cycle to a circular fuel cycle, where harmful combustion waste products are converted back into useful fuels. This will have great benefits for generations to come,” said Erik Johnston, P.Eng., Project Manager for Robert Allan Ltd.

In addition to the environmental benefits of using methanol, Allen highlights that it does not need cryogenic or pressurized fuel tanks. This reduces capital cost, saves space, and allows more fuel to be carried.

Four Scania DI16 main engines, each rated at 450 kW at 2100 rpm, would provide propulsion. Converted to run on methanol by ScandiNAOS, these engines meet IMO Tier III emissions limits without any additional aftertreatment. Two engines in each demi-hull are connected to a dual-input gearbox driving a Servogear controllable pitch propeller system that caters to both maximizing sprint speed and bollard push performance. Extensive in-house CFD analysis was used to achieve a speed above 25 knots at full load displacement. The vessel design is also future-proofed permitting it to switch to green methanol as it becomes more widely available. The CTV design complies with guidelines and rules issued by Lloyd’s Register.

The 78-foot design also provides cabins for the master and two crew in the demi-hull accommodations. A spacious and comfortable technician seating area with large forward and side windows on the main deck accommodates up to 12 wind farm service personnel.

The particulars of the RAptor 2400 are:

Length Overall: 23.8 m
Molded Beam: 8.0 m
Molded Draft: 1.1 m
Methanol Capacity: 12 m3
Installed Power: 1800 kW
Speed: >25 knots