Maritime innovator Ampereship has successfully converted the passenger ferry “Uetliberg” to 100% battery-electric propulsion, is the largest zero-emission passenger ferry in Switzerland. Now operating on Lake Zurich, the retrofitted vessel demonstrates the feasibility of decarbonising existing fleets while delivering annual savings of 113,000 litres of diesel and 300 tonnes of CO₂.
With this project, Ampereship demonstrates that even large existing passenger ships can be operated in a future-proof and emission-free manner – an important step towards sustainable shipping on lakes and rivers.
The “Uetliberg” ferry is the new flagship of Switzerland’s maritime energy transition. The passenger ferry, built in 1999, was completely converted to emission-free electric propulsion by the Stralsund shipbuilding experts Ampereship and has now successfully completed its maiden voyage on Lake Zurich. At 42.4 meters long, it is currently the largest battery-powered passenger ship in the country.
At the heart of the new drive system is a 3.6 MWh battery pack with 7,200 cells. The figures are impressive:
- 113,000 liters of diesel are saved annually
- 300 tons of CO₂ are removed from the carbon footprint each year.
This efficiency is made possible by technological advances: A comparable battery pack would have weighed 40 tons just a few years ago – today it weighs just 22 tons.
“The maiden voyage of the ‘Uetliberg’ shows that we can future-proof even large passenger ships with space for up to 300 people,” says Ingo Schillinger , Business Unit Manager at Ampereship.
The “Uetliberg” is just the beginning. The Lake Zurich Shipping Company (ZSG) has already commissioned Ampereship to convert the identical ships “Albis” and “Pfannenstiel” to fully electric operation by 2027.
This collaboration has a long tradition: In 2021, ZSG ordered three electric-solar passenger ships for use on the Limmat River. Ampereship is also driving the conversion in Germany – for example, with the Warnow ferries in Warnemünde and the Wittower ferry on Rügen.
For Ampereship, this project is not only a technical success, but also a statement: Converting existing fleets offers enormous potential to massively reduce emissions on lakes and rivers. With projects like the “Uetliberg,” the company is proving that sustainable shipping is no longer a thing of the future—it’s already a reality.
