How a Ferry’s Battery Upgrade Could Redefine Green Shipping
A Hybrid Retrofit Pushes Maritime Decarbonization Forward
The MVAurora Botnia, a hybrid ferry operated by Wasaline, is about to undergo a radical transformation. Naval architecture firm Foreship is leading an ambitious upgrade of the vessel’s battery system, boosting its energy storage capacity from 2.2 MWh to a staggering 12.6 MWh—a nearly sixfold increase. This retrofit isn’t just a technical milestone; it’s a blueprint for slashing emissions in an industry desperate for scalable solutions.
“Hybrid systems like this bridge the gap between today’s fossil fuels and tomorrow’s fully electric vessels,” says a Foreship engineer involved in the project.
The upgrade combines two battery chemistries—details of which remain proprietary—to maximize efficiency and longevity. Early projections suggest the system could cut the ferry’s annual CO₂ emissions by up to 23%, a significant stride for a ship that completes over 1,000 voyages yearly between Finland and Sweden. Foreship’s role extended beyond design: they conducted feasibility studies, emissions modeling, and cost analyses while evaluating suppliers to ensure the system’s viability.
Beyond Batteries: A Ripple Effect of Efficiency
By early 2026, when the new battery is commissioned, it will supply up to 20% of the vessel’s energy demand. But the benefits cascade further. The ferry’s LNG-fueled powerplant will operate with fewer generating sets, reducing wear and fuel consumption. In port, shore power will eliminate emissions entirely—a critical advantage as cities tighten regulations on docked ships.
Foreship’s emissions modeling confirms the retrofit aligns with the EU ETS and FuelEU Maritime regulations, future-proofing the vessel through the 2040s. Notably, Wasaline may even profit from the upgrade by selling surplus carbon allowances, turning compliance into an unexpected revenue stream.
“This isn’t just about meeting rules—it’s about proving that decarbonization can be economically sustainable,” notes a Wasaline spokesperson.
The project’s next phase will see Foreship guiding detail engineering, installation, and commissioning, ensuring seamless integration with existing systems. If successful, the MVAurora Botnia could become a case study for retrofitting older vessels, offering a faster path to greener shipping than waiting for newbuilds. In an industry where change moves at the speed of tankers, this battery upgrade is a rare jolt of momentum.
