Photos by Billy Black
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A request for an electric-powered Alerion Express 33 prompted Pearson Yachts and Mastervolt to undertake the construction of an electric-propulsion version of the boat. The heart of the system is a pair of 160-amp, 12-volt DC lithium-ion-phosphate batteries from Mastervolt. The system also includes two 60-amp Chargemasters chargers designed for maximum efficiency.
The propulsion system is a 7.5-kilowatt Drivemaster motor, made by Bellman, a company that Mastervolt recently acquired.
The owner, PS reader Vincent Argiro, has installed a battery-monitoring system from Maretron that allows him to monitor battery status in real time. Cruising range is about 12 nautical miles at 4 knots, according to range/speed data he has collected. The batteries take two hours to recharge at the dock.
Although the system has the ability to regenerate power under sail, using the spinning prop to recharge batteries, this potential is still being refined. According to Argiro, Mastervolt is still working on updates to the motor controller firmware that will improve regeneration performance under sail. One challenge is Argiro’s preference of a feathering prop instead of a fixed one. He didn’t want any performance sacrifices associated with a fixed prop, nor did Pearson. According to Pearson’s Scott Bryant, the system should regenerate 3 to 5 amps with a fixed prop.
Pearson’s powerboat company, True North, is also introducing a diesel-electric hybrid 34G, which uses a 280-horsepower Steyr hybrid diesel engine.
