June 9, 2022
By Jeff Butler
Candela, the Swedish company that is revolutionizing electric boating with its hydrofoiling speedboats, has unveiled the P-8 Voyager, a water taxi/ferry version of its C8 model at the Venice Boat Show that ran May 28 – June 5.
For us in Canada taking a boat out for family outings during our (regrettably) short boating season, Candela’s paradigm-breaking technology doesn’t come cheap – the starting price of the C8 is about $390,000 CAD. But for commercial operators using the boats every day, the system makes a lot of financial sense.
The company’s C8 recreational version has been the best-selling 8 metre boat of any propulsion type in Europe this year, with over 100 orders now in the books. The same technology that makes their hydrofoiling a game changer for personal electric boats also use makes it extremely attractive for the commercial passenger boat market.
In addition to the software driven system, which adjusts the foils about 100 times per second as the boat is moving, the company developed a proprietary C-POD electric drive with twin motors and contra-rotating propellers.
The twin motors are aligned in a torpedo-like fashion to double the power of the motor without increasing the diameter and resulting water resistance. The contra-rotation further improves the efficiency of the motor by channeling and focusing any peripheral turbulence from the props.
Electric motors create less turbulence than fossil fuel boats in general, and the combined C-POD and hydrofoiling system creates a wake of only 5 cm when the P-8 Voyager is travelling at full speed of 30 knots. That makes it perfect for passenger transport in sensitive marine environments and the canals of Venice.
There has long been concern about the effects of fossil fuel boats in Venice because of the noxious fumes, emissions, inevitable oil and gas spills and noise reverberating along the walls of the canals.
The below water turbulence has also been steadily and increasingly damaging the foundations of the city’s centuries-old buildings and palazzi (palaces). The Guardian newspaper reported in 2016 that “The foundations of more than 60% of the buildings on the Grand Canal have been damaged by the wash from the waterbuses and barges.” Reports from the Great Barrier Reef off Australia show that the noise from boat engines can even cause fish to die prematurely from stress.
Hydrofoils increase range for electric boats
The Candela hydrofoils – whether on the personal C8 leisure boat or commercial Voyager – are the key to achieving long range and high speed in electric boats.
One of the challenges of electric planing boats is that the hull creates tremendous drag, draining batteries quickly to maintain the boat on plane. The hydrofoils lift the boat out of the water and reduce that friction to just the resistance of the foiling blades in the water. The boat and hull are almost literally flying.
Gliding above the friction of water, the P-8 Voyager draws only about 25 kW from the motor when cruising at 20 knots. That enables a range 2-3 times longer than any other electric speedboat – but Candela says the technology’s big boon is to the fragile marine environment and its inhabitants.
Erik Eklund, Candela’s Chief Executive of Commercial Vessels, says “From Venice to the Bahamas, it’s absurd to travel in beautiful and fragile ecosystems in speedboats that create huge wakes and burn 200 litres of gas every hour. Using our hydrofoil technology, we can make a no-compromise electric exploration vessel. You have the performance and can cruise for well over two hours at 20 knots, but there’s virtually no negative impact on the environment.”
Electric: long term savings for commercial operators
Eklund says “The service aspect is critical for commercial operators. Our aim is to minimize maintenance and to provide hassle-free ownership. The C-POD has no transmission, no noise, no oil, no cooling fluid – and no need for maintenance. It can run for 3,000 hours without service, and if anything is required, the P-8 Voyager is fully connected and updated OTA (Over The Air), for our 24/7 service department to perform remote troubleshooting.”
The much lower cost of ‘fuelling up’ with electricity rather than fossil fuel also makes a big difference over the long run for business owners. Savings obviously depend on the gas and electricity prices where the boat is located but in Europe Eklund says 90 km of range at 20 knots costs about 10 Euros. Call that 11 Euros per 100 km – which works out to about $15 CAD for the same distance.
The P-8 Voyager carries 6 passengers and two crew and will begin production in late 2022. In addition to the C8 speedboat and Voyager, Candela also has a 30-passenger hydrofoiling P-30 Ferry which will start commercial operation in 2023 in Stockholm. The intention is to eventually replace the city’s aging fleet of 60 diesel boats that serve commuters and visitors in the vast archipelago of 30,000 islands that stretches from the city center.
Reports from the Great Barrier Reef off Australia.
The Guardian newspaper reported in 2016.
Jeff Butler is based in Toronto and is the Editor/Publisher of plugboats.com, the international website covering everything electric boats and boating. He is also President of the Electric Boat Association of Canada and is busy preparing to bring electric motor boat racing and exhibitions to Toronto Harbour in 2023 for the first Toronto Solar Boat Races.