The problem with powering any form of transportation is that it requires heavy batteries. This is a particular problem for boats, as they suffer from drag in the water. To solve this problem, Candela uses hydrofoils, legs that extend through the water and act like wings, propelling the boat through the air as it picks up speed like an airplane taking off. “In port, the foils are fully retracted, so they are protected,” says Hasselskog. “But then you lower the foils and hit the throttle and off you go. The control system takes care of the whole take-off sequence, it’s like an airplane.
Hydrofoils aren’t new, but electrical power and automated controls are. The carbon-fiber Candela P-12 will have two propulsion systems powered by 180 kWh batteries, allowing it to run for three hours before needing to be recharged. 12 meters long and 4.5 meters wide, the 8.5 tonne boat will carry 30 seated passengers.
A super-fast flying boat seems like a surefire way to waste your morning breakfast, but the Candela has sensors that power an automated control system to adjust pitch and roll and pitch up to 100 times per second. to ensure a smooth ride. the weather. “Thanks to the control system, we can cut off any vertical movement of the boat,” says Hasselskog, which tends to cause seasickness. “So far, no one has gotten seasick on our boats. “
All of this means that the Candela P-12, when built, should use less energy per passenger than a hybrid electric bus, go faster than a car, and reduce fuel and maintenance costs by 40%. And because it glides over the water, it disturbs the local environment less, both above and below the water.
Candela couldn’t just expand his existing boat to build the P-12 – regulations require a thicker hull, battery fire safety systems and, confusingly, a separate lavatory for passengers and the only member. of the crew, who will be driving all the time.
Toilets aside, there’s another regulatory challenge: speed limits on inland waterways tend to be as low as six knots (7 mph), but hydrofoils are more efficient at top speed. These speed limits are for safety and to reduce wake, which boats like the P-12 do not cause. “The solution is to work with port authorities and ferry operators to get a waiver,” says Charles Haskell, decarbonization program manager at shipping consultancy Lloyd’s Register. Around Stockholm, this limit is 12 knots, although Candela has a temporary exemption during the trial.