Marine battery maker AYK Energy completed the largest retrofit ever on the hybrid-electric Ro-Pax ferry Aurora Botnia, operated by Finnish shipping line Wasaline. The upgrade took place at Turku Repair Yard in Finland. The vessel is now back in year-round service on the green corridor route between Vaasa, Finland, and Umeå, Sweden.
The new AYK Pisces+ battery system adds 10.4 MWh, nearly five times the previous 2.2 MWh system, bringing total energy storage to 12.6 MWh. This surpasses the previous biggest retrofit on the Aida Prima cruise ship by about 500 kWh.
Aurora Botnia combines the battery system with Wärtsilä dual-fuel LNG/LBG engines. The retrofit will cut emissions along the route and improve operational efficiency.
AYK founder Chris Kruger said: “We are proud to deliver this groundbreaking project on time and on budget. Marine battery technology is improving fast, with higher energy density, safety, and cost savings. Hybrid ships have a strong future, and battery systems can pay for themselves within a few years through fuel savings.”
Wasaline targeted full carbon-neutral operations by 2030 but achieved it in 2025 using biogas. Managing Director Peter Ståhlberg said: “The Vaasa-Umeå route is Europe’s first international green shipping corridor. Expanding battery capacity with AYK Energy helps make our vessel even more sustainable. Collaboration with Finland’s energy clusters enables innovative solutions like this.”
AYK has also installed some of the largest marine batteries in the world, including two 12 MWh Orion+ systems for Brittany Ferries’ hybrid-electric ships and a 6 MWh battery for the world’s first battery-methanol tug for Svitzer. The company continues to see strong demand across ferries, cruise ships, icebreakers, workboats, and container vessels.
