BNR 209 - RPA8

Scheepswerf Gebr. Kooiman BV has delivered a new patrol vessel to the Port of Rotterdam Authority N.V. (POR). The vessel, RPA 8, is a hybrid patrol vessel that can sail on both diesel as well as diesel-electric. The vessel causes considerably less wake and is significantly more efficient than comparable vessels in this segment.

The design of the vessel is an important step forwards in vessel design for these kinds of ships. The combination of Van Oossanen's Fast Displacement Hull Form (FDHF) and an underwater spoiler, named Hull Vane® make the vessel unique. Kooiman Engineering B.V. in Zwijndrecht produced the rest of the vessel design. The design was further developed in close cooperation with POR, with extremely high requirements being set for ergonomics, working environment, visibility and safety.

The aluminum vessel (25 metres in length, with a 5.4 beam and a draught of 1.36 m) is equipped with two main engines of 382 kW, 2 permanent magnet motors of 175 kW and a 50 kVA generator. The vessel can achieve a maximum speed of 35 km/h on diesel and 22 km/h using hybrid propulsion. The vessel is equipped with an exhaust treatment system and particle filters.

EFFICIENCY BENEFITS:

• RPA 8 needs just 60% of the power (2x 382 kW versus 2 x 634 kW) of its predecessor, RPA 1, to obtain the same speed of 35 km/h.
• The combination of the unique hull shape, the Hull Vane and the hybrid system ensures that RPA 8 consumes 40% less fuel than the RPA 1 & 2.
• The Hull Vane offers a fuel saving of 22% at top speed.
• The Hull Vane offers a resistance reduction of 20% at 20 km/h and at this speed a fuel saving of 25%.
• Residual heat from the main engine is used to heat the RPA 8.
• Hybrid propulsion means that at low speeds, one main engine is switched off. A permanent magnet motor works as a dynamo, providing the propulsion of both the other propeller via the other permanent magnet motor as well as power for the on-board network, enabling just 1 properly loaded diesel engine to run everything.

ENVIRONMENTAL ASPECTS:

• The main engines are fitted with an exhaust treatment system.
• The port generator is fitted with a particle filter.
• At maximum speed in hybrid mode (22 km/h), RPA 8 has NOx emissions of just 90 mg/m3. When sailing at the same speed in conventional mode (2 diesels) the emissions, including treatment, amount to 280 mg/m3.
• Less resistance means less power, which means lower fuel consumption and lower emissions.

Scheepswerf Gebr. Kooiman B.V. was responsible for the construction of the hull and the entire fitting out. Kooiman Scheepsinterieurbouw B.V. took care of the interior and joinery. The vessel was constructed according to Bureau Veritas requirements and has a green passport.

SHIP TYPE:

hybrid patrol vessel with underwater spoiler

MAIN DIMENSIONS:

• Length overall: 25,00 m
• Beam (template): 5,40 m
• Cube (template): 3,10 m
• Draught (keel): 1,36 m

PROPULSION SYSTEM:

• Main engines: 2 x 382 kW
• Bow thruster: 1 x 55 kW
• Port generator: 1 x 50 kVA
• Permanent Magnet motors: 2 x 175 kW
• Max speed (diesel): 35 km/h
• Max speed (hybrid): 22 km/h

ACCOMMODATION:

• Crew: max. 7 people

TANK CAPACITIES:

• Fuel: 2.6 m3
• Drinking water: 0.34 m3
• Black and Grey water: 0.57 m3

ERGONOMICS:

• The entire wheelhouse and accommodation areas are ergonomically designed.
• Minimising the window frames provides the crew with panoramic visibility.
• Air suspension below the wheelhouse ensures that the vessel is exceptionally quiet. Noise levels in the wheelhouse measured at 100% power were just 49 dB(A). This is comparable with the noise level of a quiet office or a rain shower. 

WAKE:

• RPA 8 generates a wake of just 29 cm at patrol speed (20 km/h). At this speed, RPA 1 & 2 generate a wake of 58 cm.