Deck furniture is made from recycled paper rather than wood, giving the ferry a total weight of 650 tonnes.

[1] Ellen's batteries were developed by Leclanché of Switzerland and are reported to be Lithium Nickel Manganese Cobalt Oxide.

[11] They are split between two battery rooms below deck and have a capacity of 4.3 MWh, larger than any other electric vessel at its time.

[1] A charging arm on the shore ramp moves with the tide and allows battery recharging while loading.

[12] Ellen was built to operate the 22 nautical miles between the islands of Ærø and Als in Southern Denmark.