The problem with powering any form of transport with electricity is that it requires a heavy battery. That is a particular problem for boats, as they are subject to resistance in the water. To get around this, Candela uses hydrofoils, whose legs extend into the water and act like wings, propelling the boat into the air as it accelerates like an airplane during takeoff. “In the harbor, the leaves are completely retracted, so they are protected,” says Hasselskog. “But then you lower the leaf and hit the gas and it goes. The control system takes care of the entire take-off sequence, it’s like an airplane.”
Hydrofoils are not new, but use electric power and automatic control. The carbon fiber Candela P-12 will feature a 180 kWh battery-powered dual propulsion system, allowing it to run for three hours before needing a charge. With a length of 12 meters and a width of 4.5 meters, the 8.5-ton boat will carry 30 passengers.
A super-fast flying boat sounds like a surefire way to lose your breakfast on your morning commute, but Candela has sensors fed into the automatic control system to adjust the height and roll and rise. altitude up to 100 times a second to ensure a smooth ride regardless of the weather. “Through the control system, we were able to eliminate any vertical movement of the boat,” says Hasselskog. “So far no one has experienced seasickness on our boat.”
All of which means that the Candela P-12 when built will use less energy per passenger than a hybrid electric bus, travel faster than a car and reduce fuel and maintenance costs by 40%. . And as it glides across the water, it has little impact on the local environment both above and below the water.
Candela can’t simply upgrade her existing boat to build a P-12 — regulations call for a thicker hull, a battery fire safety system and, confusingly, a separate toilet separate for passengers and a crew member who will be piloting all the time.
Beyond the toilet there is another legal challenge: Speed limits on inland waterways tend to be as low as 6 knots (7 mph), but hydrofoils are most efficient at speeds. maximum degree. Such speed limits are for safety and to minimize wakes, which boats like the P-12 do not cause. “The solution is working with port authorities and ferry operators to get the allocation,” said Charles Haskell, decarbonization program manager at maritime consulting firm Lloyd’s Register. Around Stockholm, that limit is 12 knots, although Candela has temporary exemption during testing.
Not all cities can use the waterway as a highway like this, but it could be an attractive idea for coastal areas. Rival flying boat manufacturer Artemis is testing its version in Belfast, while Hasselskog held talks with authorities in Istanbul and throughout the Middle East. Representatives from the Waterway Emergency Transport Authority (WETA), the agency that operates ferry services in the San Francisco Bay Area, visited Stockholm to see how the Candela P-12 was in action.
For coastal cities like Stockholm, ferries could become the equivalent of a tram without the need for the same infrastructure as a railway, although a charging system would be required. Paul Chatterton, professor of urban futures at the University of Leeds, said: “If it functions like a light rail at sea enabling hundreds of people already in cars, that’s what we do. We need more than that. “Speed is a red herring… in a large urban river environment, you need large crafts that can travel many people over short distances.”
Hasselskog argues that a large fleet of smaller boats offers more flexibility than larger ferries and could mean they are used on-demand, bypassing the need for schedules or fixed stops. The idea is also being touted by hydrogen-powered hydrofoil water taxis made by SeaBubbles, was tested in Lyon, France. Haskell says the smaller boats have another use: ferrying maintenance and supply personnel to offshore wind farms, solving the problem of getting employees to locations miles away from shore where they are not affected. seasick.
Even without top speeds, water taxis and boat buses hold promise to cities with waterways, says Chatteron. vaporettos. And in addition to carrying passengers, slow electric barges can transport goods on the road. “You can move a lot of things with little or no energy, and a lot of cities in Europe have canals,” says Chatterton. Whether it’s electric-powered flying ferries or low-energy barges, making better use of urban waterways has implications for sustainability, says Hasselskog. “You don’t need any special infrastructure, the water is just there,” he said. “That’s probably why they’re used back in the day — you go.”
