Going Green - with the Sabdes 50M

23 September 2009 By Louisa Beckett

During our “Going Green” series on environmentally aware yacht projects, we’ve examined alternative technologies for generating and conserving energy aboard megayachts from solar panels to wind turbines. But the most critical component of a viable “eco-friendly” yacht design may well turn out to be flexibility.

Australian superyacht designer Scott Blee of Sabdes Design, who dreamed up the 164 foot Sabdes 50M motor yacht, says he kept the rapidly evolving state of green technology firmly in mind while creating the hybrid-powered concept vessel.

“The thinking behind the design is to plan ahead for future system upgrades as technologies advance without the need for making major redesign and structural changes; for example, conversion to a fuel cell system is being planned for a future refit,” the designer says. He predicts “the fuel cell is probably the way power generation will change in the near future. The technology is there now; it’s just a matter of proving its ease of use, reliability, safety and keeping down installation costs.”

Looking ahead, Blee envisions “the Sabdes 50M fitted with fuel cells and hydrogen tanks. The fuel cells combined with LiFePO4 batteries would provide sufficient power to operate during standby and slow or zero-emission cruising periods. When substantial power is required, the diesel generator sets would be used. Fifty percent of usage time, the yacht could be powered by fuel cells and achieve zero emissions.”

Blee adds, “Further energy savings could be made by incorporating power-regenerating features by way of propeller shaft generators. Emissions in the diesel mode can be reduced by installing two to four generator sets, so that the number of engines running could always be closely matched to the power demand, ensuring the engines always operate under optimal load conditions. This substantially cuts fuel consumption and emissions.”

For now, however, the Sabdes 50M project utilizes a hybrid diesel/electric propulsion system, which is forward-thinking in its own right. When running at speed, a shaft motor/generator converts energy into electrical power used to recharge the onboard battery banks. While the boat is in port or at anchor, the crew can switch to the batteries to power the house load rather than running the generators. The yacht also will have retractable bow and stern thrusters that enable the captain to maneuver in “silent running” mode in low-speed situations.

Blee gave the Sabdes 50M a reverse bow and slim hull in order to reduce both wetted surface and hull “slamming” in rough sea conditions. The highly contemporary exterior design places an emphasis on large, full-length windows integrated into the superstructure and also features a crow’s nest where guests can ascend for sensational views.

The Sabdes 50M’s deck layout shows fresh thinking. The foredeck tender bay, which is designed to hold a seven-meter tender, Zodiac RIB and personal watercraft, has a “gull-wing” door that opens to port. The launch system is set at an angle, taking advantage of the hull’s narrowing shape forward. This frees up the stern to double as a “beach” area for waters-sports lovers. The large transom door opens to provide access to sea-level gymnasium within.

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