The project is funded by the European Commission, who provides 80 billion euros on research and innovation.
An innovation on this project is the ferry's capability on creating extra redundancy, because of the lack of an emergency generator. In order to achieve that, the team split the battery system in 20 separate units, each one connected to separate converters which control the energy output.
If there is an issue with one, the ferry only loses one-twentieth of its available power – a distinct advantage over the two-battery unit configuration used on other vessels.
In light of the above, Ærø Kommune E-ferry project co-ordinator Trine Heinemann noted
Redundancy is a luxury, but we do not have an emergency generator, so we are dependent on being able to operate on just the batteries. The batteries themselves serve as emergency generators for each other. Each battery unit has a control unit that keeps track of the temperature and voltage of the batteries, making sure it is within limits and if not, then in principle it will shut down.
Moreover Marine Propulsion stated that the team had as a goal to make the ferry as light as possible; To reduce weight they only placed on the vessel a very big ramp on shore, so the weight is on shore rather than the ship, keeping in mind that the majority of ferries have ramps attached to them.
Another way to reduce the ferry's weight was that they cut out one deck from the superstructure by bringing the passenger areas to the same level as the car deck, therefore saving a lot of steel. And rather than use steel, the bridge is constructed from aluminium.
Additionally, the deck furniture is made from recycled paper, making it even more lighter.
Leclanché provided the ferry with the batteries. Its Vice President system engineering, Mika Lehmusto, noted
It is a new marine-optimised model of a previous version of the batteries, which have been used in one vessel and in ground transport applications. One of the important motivations for us was to get funding to develop technology for this marine-optimised module and marine rack system.
Mr Lehmusto decrease the weight of the batteries by 15-20%. Therefore, the new module structure was the result of several months of careful 3D mechanical designing to create a light and strong, but also configurable and economical design.
Concerning batteries, the teams conducted fire testing in their labs to be sure of fire prevention measures. They altered the battery's cabinet structure, to avoid any possibility of fire.
The next step was to find the solutions in case of a fire. A high pressure water mist-based solution was chosen as well as a cold foam-based solution.
When foam is close to fire it is able to cool it.
... Mr Lehmusto added.
The charging of the batteries will be 20 minutes, and although it is not enough power for one return trip, the gap in power is topped up by having a larger battery capacity than needed. Every night the ship will also be plugged in and slowly charged.
In addition, Danfoss, who supplied the electric propulsion engines, the bow thruster engines and the frequency converter components, made all the components water-cooled. All electric products that create heat must be water or air-cooled.
Concluding, bow thrusters provide a better manoeuvrability to the vessel.