Molslinjen to Build 12 MWh Battery at Ballen Port, Denmark

Molslinjen will build a 12 MWh battery at Ballen Port, on the Danish island of Samsø, in the Kattegat. The route between that destination and Kalundborg Port, also in Denmark, is operated by the electric ferry Tyrfing, and the battery will help ensure there is always enough power for the ferry and passengers to make up to five double trips daily.

"With a battery like this, we can store enough energy for four ferry trips. This provides us with a more secure and stable power supply for our ferry route," explains Molslinjen CEO, Carsten Jensen.

The battery is a BESS (Battery Energy Storage System). It will be able to store up to 12 MWh when fully charged. This is the same amount of electricity consumed by approximately one thousand single-family homes per day.

Work on the battery packs and the search for the ideal supplier for the battery parks have been carried out in collaboration with experts from Hybrid Greentech, who have advised Molslinjen since the beginning of the project. As with the shipping company's other battery packs in the ports of Aarhus and Odden, BOS Power will supply the high-capacity battery.

At a time when the electricity grid generally struggles to meet demand, the Samsø battery can help support and stabilize the grid. The battery can store excess energy during periods of the day when consumption is low, and then that same energy and, therefore, additional capacity can be released to the electricity grid when consumption is higher and there is a shortage of capacity.

Currently, electricity on Samsø operates in a closed circuit and reaches the island via two submarine cables. The Municipality of Samsø anticipates that the new battery will be able to supply electricity to Samsø in the future in the event of a prolonged power outage from the mainland.

"Samsø has for many years been characterized by being at the forefront of the green transition. With a high-capacity battery energy storage facility, a BESS facility built at Ballen ferry port by Samsølinjen, another important step is taken in that direction," said Samsø Mayor, Per Urban Olsen.

"The BESS facility can contribute to stabilizing the electricity grid and promoting a more flexible use of renewable energies, and at the same time it can function as an emergency supply in crisis situations. This is positive for Samsø as well as for Samsølinjen and the energy system of which we are a part," added the Mayor.

Construction is planned to take place during autumn/winter 2026/2027, and the battery is expected to begin storing electricity from March 2027.