WhisperPower has announced that the San Lorenzo 106 Hybrid, the first yacht to be fitted with an intelligent, hybrid technology-based power and propulsion system developed by the brand, has recently started cruising.
This system comprises of, amongst other components, two 150 kW WhisperPower HyGen variable speed generators, which together provide up to 300 kW of power. At least 60 kW of this is used for the yachts ‘hotel load’, with 240 kW used for propulsion.
More specifically, they provide electricity for two 130 kW electric motors, which are installed in the drivetrain between the two MTU 2000 kW main engines and the propeller, used for electric sail. As soon as the MTUs are switched on, the electric engines take over the running of the hotel load from the generator.
The main objective of this particular San Lorenzo project was to provide the yacht with a speed of nine knots using the electric motors allowing the vessel to cover large distances quietly and economically, as well as being able to enter bays. According to the brand, this can result in a saving of tens of thousands, to more than a hundred thousand Euros per season.
A second objective was to make this vessel ‘quiet’ overnight whilst still maintaining comfort. As the on-board power supply was set up as three-phase 400 volt, WhisperPower developed a 10 kW three-phase inverter that enabled the air conditioning units, refrigerators, freezers etc., to continue to run. In total, 40 kW can be loaded on to the inverter.
As a backup, two 15 kW Genverters have been installed together with several DC PowerCube charge modules that quickly and completely charge the batteries either when shore power is available or via the Genverters.
All components, including the non-WhisperPower products, are connected via a central CAN bus system.
Stijn de Wit, project engineer at WhisperPower commented, “It was a wonderful experience during the sea trial with the San Lorenzo 106 to sail super silently on e-propulsion. You could only hear the water, and still, we were going at nine knots. The boost function, so adding the e-motors to the MTUs, also worked well. We achieved a speed of almost 50 knots. The semi-electric sailing was also a success with the MTU on one propeller and electric motor on the other, the diesel consumption was 40 liters per hour at a fairly decent speed.”