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Shipping and maritime

Green Shipping

Sustainable fuels

Fully electric car and passenger ferry

22. July 2020

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Islands depend on their ferries

As an island community, Aeroe depends on its ferries, which operate with a high service level. This helps the island avoid de-population, because the ferries allow the islanders great flexibility, also professionally. They also transport tourists to and from their destination.

New solutions are necessary in the transport sector, including maritime traffic

The ferries are problematic in relation to greenhouse gases (GHGs). Maritime traffic in general is a source of significant GHG emissions and particle pollution of watershed. Implementing new sustainable solutions is a necessity in the industry as a whole. This is certainly also the case on Aeroe, where transportation accounts for up to 40 percent of the total GHG emissions, not least because of the ferries.

However, in 2015, a group of local maritime experts decided to sketch plans for what would be a revolutionary, fully electric ferry which would need to achieve an unprecendented distance between battery charges. The group presented their idea, and the municipality was keen on the idea and decided to take on the project by supplying a project lead and an information manager/fund raiser. EU’s Horizon 2020 research and innovation programme decided it would help fund the project if the municipality could find a number of European partners who were up for the task, technically – and to make a long story short, the ferry was completed and ready for operations in 2019 with the help of nine European partners.


E-ferry Ellen is a record breaking emission free solution, made on Aeroe

Ellen has been in full operation since 2019, sailing around 40 kilometers between charges, which is seven times longer than any other electric ferry in operation.

The Ellen is emission free in operation. When charged with electricity from renewable source (wind turbines supply the energy for Ellen on most days) the ferry is operating truly emission free, which indeed signifies the complete energy transformation the island envisions.

The E-ferry was designed on Aeroe by Consulting Naval Architect Jens Kristensen, and built on Aeroe by Søby Shipyard (Søby Værft).


In comparison to the old diesel ferry it replaced, emission reductions per year:

– 4000 tons of CO2
– 70,8 tons of NOx
– 2,4 tons of SO2
– 3,1 tons of CO
– 1,4 tons of particulate matter.

In comparison to a modern state-of-the-art diesel ferry, emission reductions per year:

– 2520 tons of CO2
– 14,3 tons of NOx
– 1,5 tons of SO2
– 1,8 tons of CO
– 0,5 tons of particulate matter

The energy efficiency of Ellen’s systems (transformer to propeller) is remarkable:

85 % (more than twice that of a diesel)

The life-cycle economy is better than for a traditional diesel ferry

The island recommends duplicating the fully electric solution. Not only does it reduce emissions significantly, its lifecycle economy is better than for a traditional diesel ferry, because electricity is cheaper than diesel, and because maintenance requirements are very low compared to a traditional diesel-driven ferry. And even if the E-ferry is charged with electricity from fossil fuel sources it will reduce emissions significantly, because of the exceptional energy efficiency of its systems.

This case is co-owned by Leclanché, Danfoss Editron, Tuco Marine Group, Consulting Naval Architect Jens Kristensen, Hellenic Institute
of Transport, Danish Maritime Authority, Søby Shipyard and Danish Institute of Fire and Security Technology