Technology group Wärtsilä has been selected as the electrical integrator for a major battery extension project for the Wasaline ro-pax ferry Aurora Botnia. The project will increase the ship’s battery capacity by 10.4MWh, from 2.2MWh to 12.6MWh, making it the world’s largest marine battery hybrid system in operation. The order with Wärtsilä was booked in Q3 2025.
The Aurora Botnia, which is operated by Wasaline, is equipped with dual-fuel engines and batteries and uses biogas and batteries for propulsion. Expanding its battery capacity is a major step in making the ship even more sustainable. Wärtsilä will lead the integration project and as a result, the battery capacity of the ferry will be extended by 10.4MWh. Wärtsilä will also deliver the energy management system, as well as upgrading the power drives and the control system integration. The system is scheduled to be commissioned in early 2026.
“Wasaline’s commitment to decarbonized shipping operations is central to everything we do,” said Peter Ståhlberg, managing director of Wasaline. “In this, our close cooperation with Wärtsilä is an essential element that benefits not only both our companies, and we can see that our cooperation sets standards for the whole marine sector. Through our continued collaboration, the Aurora Botnia has become a working example of what is possible when it comes to delivering environmentally friendly transportation within shipping.”
This latest project will strengthen the existing collaboration agreement between Wärtsilä and Wasaline, with the Aurora Botnia acting as a floating test lab linked to Wärtsilä’s Sustainable Technology Hub. It allows further development of hybrid technologies to optimize fuel efficiency and minimize exhaust emissions.
“Wasaline once again demonstrates its strong commitment to decarbonization by extending the electrification capacity of this ferry,” added Roger Holm, president of Wärtsilä Marine and executive vice president at Wärtsilä Corporation. “Our latest contribution will optimize the ship’s operations even further, creating fuel savings and a significant reduction in emissions.”
The Aurora Botnia, which entered into service in 2021, operates with a range of integrated Wärtsilä solutions, including four 31DF engines. The ultra-low emissions version of the engine has helped the ferry to significantly reduce methane emissions. The ferry operates between Vaasa in Finland and Umeå, Sweden.
In related news, Arriva Shipping is constructing a dry cargo vessel with a battery hybrid system