“Maybe we will save this world after all.” Halfdan Ambrahamsen, Aeroe, Denmark
Aeroe, Denmark, is an island with a population of 6,000. All the buildings in the island are emission free. It produces 125% of its electricity by 6 wind turbines and solar provides 55% for a district heating system.
All of these are locally owned which means the benefit remains in the island. In the words of Halfdan Ambrahamsen “The Aeroe way is cooperative.”
Aeroe is served by 4 ferries. One of those is the first all-electric vessel – Ellen.

Everything about the Ellen is electric. It can carry 200 passengers and 31 cars. It is non polluting, has zero noise and less vibration making it more comfortable for passengers.
Dean Jennings, of Leclanche, has called this the ‘electrification revolution’. Currently 90% of goods are transported globally by sea. This is a huge contributor to Co2 emissions – more than 40%.
Ellen is 85% energy efficient and can travel 22 nautical miles before recharging.
Halfdan explained that you need the power grid landside to deliver the recharging necessary. They have this on Aeroe due to the renewable energy they produce. The shoreside technology is a vital part of the success of the e-ferry. When asked if hydrogen fuel was a possibility, Halfdan, said that because their locally produced energy goes into the power grid it would not make sense to convert this to hydrogen. Hydrogen fuel cells are 50% efficient compared to the 85% efficiency of the batteries used on Ellen. Hydrogen, however, may be of more use on longer distances.
Initially Ellen was expensive as it was a first. It cost 30 million Euro. Half of this, 15million Euro was funded by the EU’s Horizon 2020 initiative. If another Ellen was to be built the cost would now be much less – estimated at 16million Euro. The savings come in that over 10years it will be 24 – 36% cheaper than Diesel.
The ferry travels between the Danish port of Fynshav to Soby, on the island of Aeroe where it is charged overnight. It can be recharged rapidly within one hour but they tend not to do this because it reduces battery life and uses up a lot on energy.
The Ellen has been passed as safe for which new regulations had to be developed.
Norway and Canada are well ahead in the electrification of vessels. Sverre Erikson, DNV GL, Norway, explained the growth in the electrification of vessels. In 2011 there were 2, in 2020 there are 120 sailing and 110 being built. These vessels are hybrids – they are electrified but have a diesel back up. The Ellen is all electric, it has no back up.
The growth in electrification of vessels is now seeing a new project every week. Some existing ferries can be retro fitted but the advantage of Ellen is that the design from the start was for a hydro dynamic and light vessel, inspired by old sailing ships.
The Ellen was the subject of an online talk during the Virtual Islands Summit hosted by Island Innovation on Wednesday 9th of September.
Reporter: Fiona Grahame
Categories: Science