Cars aren’t the only conveyances being transformed by electricity. Along with electric motorcycles and snowmobiles, personal watercraft are floating better ways to coexist with nature and neighbors. This new breed of machines brings requisite thrills to the Great Outdoors, but without fouling the atmosphere or disturbing the peace with an internal-combustion racket.
The latest comes from Florida-based Pelagion, whose founder and chief executive, engineer Jamie Schlinkmann, was inspired by childhood adventures on a watersports icon: A 1973 Kawasaki Jet Ski. Schlinkmann’s machine, just the 213th ever built, is still one of his prized possessions. His company’s Pelagion HydroBlade is an ingenious mash-up of classic stand-up Jet Skis and modern surfboard-style “eFoils.” Those electric-powered boards had a real breakthrough in 2020 when Facebook founder Mark Zuckerberg was spotted sailing over Hawaiian waters on one model.
[embedded content]Footage of the HydroBlade Prototype During Field Testing in South Florida
The metaverse may spring to mind the first time you see an eFoil, with its rider seeming to fly above the waves on a magic carpet. Naturally, there’s no magic, only hydrodynamics. Hydrofoils work like an airplane wing, only underwater: An aerodynamic wing creates high and low pressure areas as it slices through water, generating lift with precious little drag. Add an electric motor and propeller to create thrust and you’ve got a hydrofoil that doesn’t require surf waves, a kite, or tow boat to generate power.
“They’re kind of like flying an airplane with no rudder and no ailerons,” Schlinkmann says. “You shift your weight to fly that plane.”
There’s only one problem: Powered or not, a hydrofoil takes some practice and patience to learn to ride in a standing position, especially for people with no surfing or wakeboarding experience, or so-so balance skills. To solve that, Schlinkmann’s invention adds a boom-mounted canard and rudder ahead of the rider to keep the craft airborne and steady without a rider having to constantly expend energy and adjust body position. Add a trusty set of handlebars, says Schlinkmann, and the HydroBlade handles more like a vehicle with which most of us are familiar: a bicycle. Making the experience somewhat like riding a bike, he says, helps ease the intimidation factor and boost appeal for people of all ages and abilities.
“There’s a lot lower learning curve,” Schlinkmann says. “Like a bicycle, you lean into a curve, and add another control element.”
The design began to take shape around 2020. Schlinkmann pulled the engine and other ICE guts from his old Jet Ski and studied how he could make it electric. He realized a conventional electric Jet Ski might only have a 15- or 20-minute runtime on a single charge, which wasn’t good enough. But after riding a few eFoils, the idea came together.
“The foil improves efficiency so much,” he’d said. If I could make something that combined the two worlds, he thought, we’d get the range and usage that’s practical.
For the HydroBlade, a pair of permanent-magnet radial-flux motors drive dual propellers at a peak 16 kilowatts (21 horsepower). They’re fed by two battery packs, with a combined 600 cylindrical 2170 NCM cells and a total 11 kilowatt-hours of energy—about eight to 10 times the capacity onboard a typical eFoil. A separate 1.6-kW charger can refill batteries in about 4 hours.
Schlinkmann says the HydroBlade should cruise for about 4 hours at hair-whipping speeds of up to 70 kilometers per hour (44 miles per hour). The company is targeting a 60-mile range, enough to get from Ft. Lauderdale to Bimini on a charge. The twin battery packs weigh 58 kilograms, a bit more than half the craft’s total 104 kg weight. The removable, swappable packs act as stressed members for a hull that’s skinned in ABS composite. A smartphone app doubles as an electronic dashboard. Put the phone in the craft’s handlebar mount and get readings including speed, state-of-charge, and telemetry.
Putting that much juice underwater requires special attention to safety—the first concern many people have about electric watercraft.
“If you’re in a Tesla and catch fire, you just get out,” says Schlinkmann, a longtime Model S owner. “If you’re on the water and catch on fire, you’re swimming.”
Schlinkmann says the company’s battery-management system monitors the health and state of individual cells and communicates along a typical CAN bus. The in-house design also fuses cells in parallel at a notably low current for cell balancing, keeping power current on a separate path.
“We’re fusing the cells at a much lower level, so if there’s any cell failure, you won’t have a fire,” he says.
The company is aiming to tool up production in coming months, and to bringthe HydroBlade to customers by around year’s end. Initial capacity, according to the company, will be 1,000 units a year. Next time you’re lolling on a beach, keep your eyes peeled for a HydroBlade—because you certainly won’t hear it shrieking past.
This article appears in the May 2023 print issue as “Reimagined Jet Ski Brings EVs to the Beach.”
Original Source: https://spectrum.ieee.org/electric-jet-ski