The Port of Rotterdam Authority recently commissioned Kooiman Shipyard to construct a RPA8 hybrid patrol boat with the stipulation that special engines be used.
During the tender process the authority paid particular attention to cost of ownership, emission reduction and minimising wave generation. The tender also specified that the innovative patrol boat would be equipped with a hybrid propulsion system combining diesel electric and diesel direct power; diesel electric fed to one of the engines up to a speed of 25 km/h and diesel direct for both main engines at speeds between 25 km/h and 35 km/h.
By correctly loading the engines, the RPA 8's combustion is more efficient, which reduces fuel consumption and emissions. An after-treatment system further limits the emission of hazardous substances. Moreover, heat recovered from the engines' cooling water system heats the deckhouse.
The right engines
MAN Rollo supplied two MAN D2676LE424 engines for the hybrid patrol boat. This is mainly down to the fact that the Port of Rotterdam Authority is striving to become a sustainable port.
Karel Schuurman, sales manager at MAN Rollo says: ‘The engines are very modern and feature the latest common rail fuel injection technology. As a result, their fuel consumption is low and the exhaust emission levels are lower than that prescribed by the current global emission standards.’
This is a major advantage, because the patrol boat will operate in a busy urban area with much waterborne traffic. ‘The engines from this heavy-duty range each generate 382 kW@1800 rpm and are the best option for the RPA 8 with respect to dimensions and weight,’ says Schuurman.
The RPA 8 will operate in the Port of Rotterdam from September onwards. The vessel is envisaged to become the new standard for patrol boats used in inland and coastal waters.
Special hull design
The Kooiman shipyard also collaborated with the Van Oossanen group, which designed a hull specifically for the RPA 8. The hull is a combination of two patented inventions: the Fast Displacement Hull Form and the Hull Vane. This minimises wave generation and results in a 20% reduction in resistance of the vessel at top speed. To reach the desired top speed (35km/h), 736 kW is sufficient.
