Highly customised Heesen 50-metre Steel hybrid yacht for delivery in 2024

by Heesen Yachts 24 Dec 2020 14:30 UTC

• Hybrid propulsion
• Exterior lines by Clifford Denn
• Interior design by Luca Dini Design and Architecture
• Glass-bottomed pool
• Outdoor fire pit
• Expansive wellness area

Heesen is proud to announce the sale of a highly customised motor yacht based on the proven platform of the 50-metre Steel Class. YN 20150, code-named Project Oslo24, is the fifth yacht sold by Heesen in 2020, and the second sold in December.

The client, an accomplished yachtsman who will also captain the boat, has introduced a wealth of practical and technical ideas from his many years of sailing experience, which will make this yacht unique.

Intent on minimising the vessel's environmental impact, the owner has opted for a hybrid propulsion system that embraces the best of 21st-century technology. Heesen's hybrid system offers incontrovertible advantages over traditional diesel propulsion, and will ensure that Project Oslo24 is cleaner, quieter and more efficient than comparable conventional craft.

The hybrid drivetrain can draw on diesel engines and electric motors, together or individually, for both propulsion and hotel needs. In automotive engineering such systems emphasise energy saving and reducing emissions, but hybrid propulsion at sea has a wider set of aims. Silent cruising and zero vibration enormously enhance comfort levels on board, and are especially appealing during night passages.

The heart of the hybrid system is the yacht's twin MTU 8V4000 M63 (IMO Tier III) main engines, each coupled to a water-cooled, 135kW Danfoss electric motor on the same propeller shaft. This configuration offers versatility of operations, flexible power management, and redundancy, thanks to its three cruising modes:

1. Silent mode for low speeds: Electric propulsion only. The main engines are shut down and the E-motors drive the propeller shafts. The main generators provide electrical power for the E-motors and the yacht's systems and stabilizers. This mode is beautifully silent and free from vibration as the generators are fully insulated and boxed.

2. Economic mode with power take-off (PTO): Direct diesel propulsion. The main engines drive the prop shafts to propel the yacht. The main generators are shut down, while the E-motors use the turning shafts to generate electrical power in PTO or "shaft generator" mode, feeding the yacht's systems and stabilizers. This mode is ideal on long passages: by saving working-hours on the generators, it extends their life and at the same time reduces fuel consumption.

3. Cruising mode - without PTO: Direct diesel propulsion only. The main engines drive the prop shafts to propel the yacht. The main generators provide the necessary electrical power for the yacht's hotel load and stabilizers.

This brilliant technology is beautifully wrapped in an elegant and timeless exterior penned by Clifford Denn. Conceived for cruising in fjords, rivers and canals, Project Oslo24 also sports a folding mast that will allow her to negotiate bridges with a clearance of 13.4m.

The yacht's layout reflects the lifestyle of the owner and his family in every detail. Italian firm Luca Dini Design & Architecture have been briefed to create a refined but relaxed décor for both the guest and crew areas.

A helm station on the flybridge will allow the skipper to enjoy the company of family and friends while under way. Meanwhile, on the wheelhouse deck, the owner has specified the captain's cabin as his private office, with a fold-out bed for use during long passages. His master suite is located on the main deck forward, while there is also a full-beam suite and office on the lower deck, where the remaining guest cabins are also found.

On the main deck aft terrace there is a glass-bottomed pool with waterjets over the beach club, with its expansive wellness suite. Along with the forward seating area, complete with fire pit, these will be perfect places to enjoy life outdoors.

"Oslo24 is a very exciting project and we are carrying it out with enthusiasm and confidence as we know both the client and the shipyard well" comments Stefan Zucker of Zucker and Partner, owner's representative and building surveyor.

YN 20150 Project Oslo24 is due for delivery in March 2024.