Fishing vessel’s power modes include hybrid system

View of the Herøyhav's engine room featuring an MAN 9L27/38 main engin

MARCH 25, 2014 — Norway’s Herøyhav AS, has taken delivery of a 69.95-m trawler/purse seiner from Karstensens Shipyard, Denmark, that has a very flexible propulsion package offering a number of fuel-saving power modes to accommodate the different fishing patterns the vessel will encounter at sea.

The Herøyhav was ordered by the Ervik family of Fosnavåg, Norway in January 2012 to replace a previous vessel of the same name delivered in 1999.

The new fishing vessel has been updated with modern equipment that provides flexible and economic operation, both for pelagic trawling and purse-seine fishing in the Atlantic adjacent to the Norwegian coast.

The propulsion package consists of a MAN 9L27/38 engine and a two-speed reduction gear that drives a MAN Alpha 4,200 mm diameter ducted propeller. The propeller nozzle is a customized MAN Alpha AHT design. MAN Diesel & Turbo also supplied its Alphatronic 2000 propulsion control system, including the ECO Speed Pilot for optimal voyage planning and speed setting.

A hybrid configuration is a fuel-efficient and flexible power-and-propulsion system with high redundancy. Hybrid propulsion systems are a combination of electric propulsion and diesel drive, and enable ships with variable power requirements to run at high propeller efficiency. A large number of operational modes are available, which enable the engine and propeller to run optimally over a wider power range.

The Herøyhav’s propulsion system has several power modes: both diesel-mechanical, diesel-electrical and hybrid combinations.

Its auxiliary generators can deliver 1,500 kW auxiliary power to the hybrid system, which – in combination with the main-engine power of 3,285 kW – offer a total propulsion output of 4,785 kW (about 6,500 hp) for trawling or full-speed steaming.

The following ship speed / power modes were verified during sea trials:

• 11.6 knots – 1,400 kW (diesel-electric, variable propeller speed)
• 14.0 knots – 2,400 kW (diesel-electric, fixed propeller speed)
• 15.5 knots – 3,285 kW (diesel-mechanical)
• 16.6 Knots – 4,785 kW (diesel-mechanical + electric boost)

As a result of the fuel-saving propulsion setups for the various operational modes, the Herøyhav also limits exhaust gas-to-air emissions. Another environmentally friendly feature is its coated propeller shaft, installed in combination with a water-lubricated stern-tube system, that eliminates any risk of sealing damage and any leakages of stern-tube oil to the sea in the event of impact with fishing gear wires.

Karstensens Skibsværft A/S is a modern shipyard with some 250 employees at its newbuilding and repair/service facility in Skagen, Northern Jutland. The yard is capable of building a broad variety of ship types up to a length of about 135 m including fishing vessels, tankers, freighters, ferries, naval offshore patrol vessels, and other special-purpose vessels. The yard has built over 400 vessels since its establishment in 1917 with Herøyhav being designated hull number 423.