Fully-electric ferries: Electricity and water – a good combination

Aug 3, 2021

Whether it is people, cars or trucks – ferries transport heavy loads, and therefore consume a lot of energy. So it is all the more important that they make the change to emission-free drive technologies as quickly as possible.

Decarbonization is the order of the day in the mobility sector. Whether it is cars, buses, trucks or aircraft – there’s no mode of transport where the drive is not currently being changed over to climate-friendly technologies. The subject has already been addressed for ferries too. The background to is that is the increasingly stringent environmental regulations of the International Maritime Organization (IMO): 2020, which lowered the global maximum values for the sulfur content of emissions from shipping from 3.5 to 0.5 percent. For specially-protected waters, such as the North Sea and the Baltic Sea, the levels are just 0.1 percent. The shipping companies need to respond, and in doing so various options are open to them: From retrofitting to run on liquefied natural gas (LNG) to using stronger filter systems to hybrids with rotor sails. But pure electric is also possible: On the North German coast, in the Norwegian fjords, in Portugal, Sweden and Thailand – five locations where battery-driven ferries are already operating.

The MS Düsternbrook. © SFK

North Germany: First electric ferry in Kiel, mini-ferry to Usedom

The “MS Düsternbrook” operated by the shipping company Schlepp- und Fährgesellschaft Kiel (SFK) is the first fully electric ferry on the coast of North Germany. The ship has been operating on the “F2 Schwentine Line” on the Kieler Förde inlet since June 2021, where it links the landing stages at Reventlou, Wellingdorf and Neumühlen with one another. At just under 25 meters in length and a little over 7 meters wide, the ferry is one of the smaller versions of its type. But its solo deck is still capable of transporting around 140 people and 60 bicycles. The ferry is powered by two electric motors, each delivering 86 kilowatts of power, and a 40-kW bow thruster. Its battery, dimensioned for 819 kWh, together with the 20 solar cells is sufficient for around ten hours of operation. In total, the costs for the ship have reportedly run to around EUR 3 million, with SFK receiving support for the purchase from the German Federal Ministry for Transport and Infrastructure (BMVI). The ship was built by Holland Shipyards in Rotterdam.

Another e-ferry in North Germany is set to go into operation from August 2021 between the island of Usedom and Kamp on the mainland. At just 14 meters long and with a capacity of 20 people and 15 bikes, the ship is a lot smaller than the MS Düsternbrook in Kiel. The solar ferry is due to operate for between eight and 14 hours a day, allowing it to recharge its batteries overnight. The mini-ferry was developed with a fully electric rudder propeller from Torqeedo, a German manufacturer of electric powertrain systems for boats.

Norway: “Bastø Electric”, the world’s biggest e-ferry

Things that work on a small scale can also work on a huge scale, as the Norwegian shipping company Bastø Fosen impressively demonstrates. With its giant ship “Bastø Electric”, it is operating what is currently the world’s biggest electric ferry. Almost 140 meters long and fully 21 meters wide, this colossus can accommodate up to 600 passengers and 200 cars. The ship has been operating since March 2021 between the two towns of Moss and Horten, located on the eastern and western shores of the Oslo fjord. This route is Norway’s most heavily-traveled ferry link, and around 3.8 million passengers and around 1.8 vehicles use this crossing every year. The ship (in whose development Siemens had a hand) draws its power from a battery with a capacity of an incredible 4,300 kWh. As a comparison, the biggest batteries in cars currently offer something under 100 kWh. When it comes to electrifying ferries, Norway is considered a trailblazer. In total, over 70 e-ferries are already in use on the many bodies of water in that country.

The world’s biggest e-ferry: Bastø Electric. © Bastø Fosen

Portugal: e-ferry to Lisbon

Diesel for electric – that’s the route the transport company Transtejo is also taking; it operates several ferries crossing the Tejo river in the Portuguese capital Lisbon. By 2022, the company is looking to replace ten of its diesel ships with new electric models, which it has commissioned from the Spanish shipbuilders Astilleros Gondán and the Swedish industrial giant ABB. The 40-meter ferries will be able to accommodate up to 540 passengers and operate between landing stages in Lisbon, Cacilhas, Seixal and Montijo, all of which are on the Tejo, the longest river on the Iberian Peninsula. The ferries are due to go into service in the years 2022 to 2024. The first ship is set to have a battery capacity of 1,860 kWh and be capable of speeds up to 16 knots (30 km/h). “This project is a further milestone for emission-free powertrain solutions in the ferry industry and shows that a proven technology is already available today that enables us to satisfy the future requirements for sustainable ferry transport,” says Juha Koskela, Head of the Marine & Ports division at ABB.

From 2022, the new electric ferries are to sail on the Tejo River. © Astilleros Gondán

Sweden: The world’s fastest electric ferry

Instead of setting speed records, ferries are usually notable for a relatively sedate pace of travel, which is certainly advantageous for electric ships in terms of saving energy and range. However, e-ferries are also capable of different, as a model planned in Stockholm called the P-30 shows. At up to 55 km/h, the 12-meter vessel will in future travel the “waterway” between Stockholm and the archipelagoes on a nearby island. The stylish e-boat has space for around 30 people, and is powered by two electric motors each with an output 60 kW. Batteries with capacity of 180 kWh are set to enable the high-speed ship to travel around 110 kilometers. How is that possible? The ship is fitted with hydrofoils, allowing it to lift off slightly as it travels over the water. That lowers resistance and makes higher speeds and longer distances possible.

The world’s fastest electric ferry. © Candela

Thailand: e-ferries between skyscrapers

The change in thinking is also taking hold beyond Europe – Thailand, for instance, is making an impact in electromobility and is looking to electrify at least 30 percent of its transport systems by 2030. In Bangkok, the country’s capital, twelve older ferries were recently converted to that end. Instead of diesel outboard motors and fuel tanks, the fiberglass boats are now powered by lithium-ion batteries and, on each boat, two fully-electric outboard motors from the German manufacturer Torqueedo. The ships are part of a city-wide plan for CO2 reduction and part of a bigger fleet which includes a further 20 e-ferries. With a capacity of 30 people, the ships are intended to achieve lower emission levels on the inner-city waterways and help commuters to cross the canals and rivers.

(Stagephoto: © Levent Simsek/Pexels)

The fiberglass boats are powered by an integrated battery electric propulsion system from Torqeedo. © Torqeedo

The IAA MOBILITY is transforming itself from a pure car show to an international mobility platform with four pillars: the Summit, the Conference, the “Blue Lane” and the downtown Munich Open Space. Under the slogan of “What will move us next”, it stands for the digital and climate-neutral mobility of the future. From 7 to 12 September 2021, the car, bike and tech industries come together at IAA MOBILITY in Munich.