Charging several times along the route, the P-12 travelled north from Gothenburg in Sweden to Norway’s capital Oslo, via part of the Skagerrak strait that links the North Sea to the Baltic. According to Candela, the journey demonstrates that electric ferries are no longer limited to short, fixed routes or reliant on bespoke and costly charging infrastructure.
“Charging infrastructure is the hidden cost of electrifying conventional vessels,” said Gabriele De Mattia, project engineer at Candela and lead engineer for the Gothenburg to Oslo voyage.
“In many cases, building megawatt-scale chargers – especially where the grid is weak or undeveloped – can cost as much as the vessels themselves. The breakthrough with P-12 is that it is fast to charge and extremely flexible in where it can operate.”
Candela undertook the voyage to highlight this contrast between the P-12 and existing electric ferries, several of which operate in and around Oslo. The city’s fastest electric passenger ferry, m/s Baronen, operates a fixed 10-nautical-mile route and relies on swapping a deck-mounted battery container with several megawatt-hours of capacity at the end of each trip. The automated battery-swapping system alone has cost hundreds of millions of Norwegian kroner, according to Candela.
By contrast, the P-12 requires much less infrastructure and can operate across longer routes. Its computer-controlled hydrofoils extend from beneath the boat’s hull, allowing it to travel above the water at speeds in excess of 20 knots. As well as enabling speed, the hydrofoils also make the P-12 exceptionally efficient, using around 80 per cent less energy compared to conventionally fuelled vessels. This means it can be charged using easily deployed high-speed DC infrastructure that is now common in the automotive sector.
On the voyage to Oslo, the P-12 charged used a combination of existing DC charging infrastructure along Sweden’s coast, along with a portable 360kW Skagerak Energi Move DC charger connected to a mobile battery system, which was towed behind a Ford F-150 Lightning electric pickup. The journey was completed over three days, with demonstration and charging stops along the route. Candela claims the electricity needed to power the journey cost just over €200.