Hybrid system generates savings, quiet and speed
DRACHTEN ~ The project faced steep challenges in order to save something like €100,000 each year in fuel charges. WhisperPower had to deliver a motor yacht able to cruise at 9 knots on electric power over large distances, quietly. Also, the 106ft (31.7m) Italian-built superyacht (photo) had to be quiet overnight while running all systems that guarantee onboard comfort.
With the onboard power supply set up as three-phase 400 volt, WhisperPower developed a 10 kW three-phase inverter that let air conditioning units, refrigerators, freezers etc. to continue to run. In total, 40 kW can be loaded on to the inverter.
The San Lorenzo 106 was the first yacht to be fitted with an intelligent, hybrid technology-based power and propulsion system developed by WhisperPower. It features two 150 kW WhisperPower HyGen variable-speed generators that together pack up to 300 kW. , including at least 60 kW for the “hotel load.” More specifically, they provide electricity for two 130 kW electric motors installed in the drivetrain between the two MTU 2000 kW main engines and the propeller and are used for electric sail. As soon as the MTUs are switched on, the electric engines start running the hotel load from the generator.
“It was a wonderful experience during sea trials with the San Lorenzo 106 to sail super silently on e-propulsion,” says WhisperPower Project Engineer Stijn de Wit. “You could only hear the water and, still, we were going 9 knots. Adding the e-motors to the MTUs gave a speed of almost 50 knots. In semi-electric sailing, the diesel consumption was 40 l/hr. at a fairly decent speed.”
WhisperPower delivers power & propulsion systems for yachts and commercial vessels from 16 to 60 meters. The company showed off its San Lorenzo-106 hybrid power & propulsion system at the SuperYacht Pavilion of the 2015 Marine Equipment Trade Show in mid-November. At a separate location, it displayed a raft of new products for boat builders, installers and dealers including the new Supreme PRO battery charger/ power supply for commercial shipping and the luxury yacht sector.