Smooth sailing
17 SEPTEMBER 2025
How Scania and Blidösundsbolaget are pioneering quiet and clean electric ferry power in the Stockholm Archipelago.
Since Midsummer, commuters and tourists in part of the Stockholm Archipelago may have noticed how quiet and clean one of their usual ferries is. The difference is striking compared with the normal clank and grind and diesel smells of the many boats that ply this beautiful area in and around the Swedish capital.
That’s because the M/S Silverö ferry, which sails between the Vaxholm and other nearby islands, has been retrofitted with a fully electric Scania e-machine.
The pioneering passenger boat is the latest exciting example of the longstanding and highly productive partnership between Scania as engine maker and Blidösundsbolaget, the largest ferry operator in the Stockholm region.
“Over the years we have built up a close cooperation with Scania as our provider of diesel engines and selective catalytic reduction systems for our boats,” says Fredrik Liw, Blidösundsbolaget’s Technical Superintendent. “In 2018, our M/S Rex ferry was fitted with a Scania hybrid electric engine and that has been a success.”
“So, 18 months ago, when the time was right for considering full electrification, we asked Scania to work with us on fitting an e-machine so we could test it under real working conditions.”
Fredrik Liw, Blidösundsbolaget’s Technical Superintendent
The M/S Silverö ferry was identified as the ideal candidate for the retrofit of a 330kW prototype e-machine already in use for trucks. Even though the boat was built as far back as 1970, she has remained a steadfast member of the company’s fleet, and her strong hull and overall structure are still in great condition.
It also helps that the e-machine weighs just 400 kilos, less than a third of that of a diesel-engine equivalent, with a much smaller footprint too. Its four gears means perfect propeller matching, and the twin installation allows counter-rotating propellers for efficiency without heavy marine transmissions.
Running daily and reliably since Midsummer
Despite being set a challenging target date of launching by the Thursday before Midsummer Day on 21 June, to qualify for the summer timetable, Scania worked non-stop from February to June with Blidösundsbolaget so that the electrified M/S Silverö was ready.
“We’ve been running the ferry daily since then with no major issues, and we’re very happy with how she’s performing,” says Liw. “She’s a spider at the centre of the web from the Vaxholm base, and goes on short trips to nearby islands. A lot of other boats depend on her for changes, so the Silverö goes from and to islands close to Vaxholm.”
In fact, the main challenge since then has not been the operation but the charging infrastructure for the batteries powering the vessel, which led to temporary solutions for a couple of weeks.
Blidösundsbolaget’s electrical partner Marinelektro has since established a permanent charging solution next to the ferry’s mooring point. Up to 450 KW of power can be stored there, and the vessel, which has a capacity of 780 kilowatt hours, can be charged with 400 KW at a time. The charging takes place at night or during breaks during the ferry’s daily schedule.
Scania: Blidösundsbolaget a perfect partner to test our electric motor
For Scania, the M/S Silverö represents an ideal opportunity to undertake a long-term field test of the new e-machine, which won’t be on the market for marine applications until Blidösundsbolaget has completed its exclusive two-year pilot phase.
“I think we’ve found a perfect place for going electric, together with a company who has been a long-term partner for us, with whom we’ve done a number of pilots now,” says Torben Dabrowski, Global Key Account Manager (Marine) at Scania, who has travelled on the ferry himself and remarks on the “strange but pleasant sensation of being on a quiet ferry with none of the usual noise and shaking.”
He adds, “It’s easy to work with this customer. There’s no stress, and they share our vision of proving electric propulsion can work in passenger ferries.
“It’s Scania and Blidösundsbolaget taking ferry boat transport into the next level of zero-emission possibilities. We’re showing it can be done.”
Fredrik Liw believes that having a tried and tested emission-free concept by the time the next Stockholm region ferry contracts are up for renewal in April 2028 will stand Blidösundsbolaget in good stead. He praises the collaboration between the ferry company and project partners Marinelektro, Teqc and Marinbolaget, as well as the ongoing cooperation with Scania.
“Scania’s size, expertise and scalability give us cost advantages compared with niche marine suppliers,” he says. “We hope that electric power becomes a long-term solution for marine applications – and so far, it looks like it will.”
