The 44-metere eco friendly yacht will use Siemens SIShip Eco Prop system for greater efficiency.

Perfecting its plans for a more environmentally friendly motor yacht, Kingship Marine announced the inclusion of the Siemens SIShip Eco Prop system in its Green Voyager. The innovative 144-foot (44-meter) Green Voyager was designed for the owner who seeks a low-impact vessel to cruise the globe; an owner who wants to cruise responsibly, but doesn’t want to compromise on luxury and comfort.

The foundation of Green Voyager’s lowered impact is compliance with RINA’s Green Plus Class notation. Kingship’s engineers and designer Axis Group Yacht Design of Viareggio, Italy, are concentrating on increasing efficiency in every area. Solutions will include heat-reflecting glass, high-efficiency insulation, heat recovery, heat-pump calorifiers, exhaust gas treatment, ultra-efficient props, bio lubes and fuels, environmental operations manuals, smart HVAC, a zero discharge sewage and grey water treatment plant and more.

Kingship’s aim is to reduce the yacht’s power demand by an average of 20 percent. Tank testing has proved the Green Voyager is optimized to be at least 16 percent more propulsion efficient than a conventional yacht of the same size. The hull efficiency is helped by a waterline length that is just 19.7 inches (50 cm) shorter than the yacht itself. Efficiency rewards the owner twice: once for protecting the environment and then again in operational cost savings.

To fulfil Kingship’s three propulsion criteria—low energy consumption, clean operation, and compact size—Green Voyager has adopted Siemens SIShip Eco Prop system. This is hybrid propulsion similar to a hybrid car. The yacht keeps a massive 400 kW hours of energy stored in compact lithium Iron phosphate battery banks. There are two size-optimised variable speed diesel generators that minimise fuel consumption. The main engines have special ZF gearboxes that turn the propeller shafts and also an AC shaft generator as required. This allows propulsion by Diesel, Diesel Electric and Battery or - at slow speed and short range - batteries alone.

The power needed aboard for air conditioning, lighting and so on is taken from generators or from the main engine shaft generator or - for long overnight periods - silently from the battery bank.
The brain of the EcoProp energy system is Siemens’ intelligent power management system (PMS). It automatically matches the demand to the source of power in each circumstance. This fulfils the Green Voyager philosophy; use every kilowatt made from every litre of diesel or store it to use later.

The PMS offers a multitude of scenarios from overnighting at anchor with HVAC on batteries, to crossing the Pacific very economically using only one main engine to propel the yacht and supply all the domestic energy needs; and with no generators running.

Green Voyager will be the first yacht in the world under 164 feet (50 meters) built to Green Plus standards. She will be less than 500 gross tons. Kingship is finalising the design phase and will start building this unique motor yacht in late 2010.