Research by the New Zealand Government has found that domestic ships such as ferries and freighters emit close to 300,000 tons of CO₂ every year. In Wellington, nearly 50% of the city’s emissions were produced from the transportation sector in 2020. With the local council committing to becoming a net-zero-carbon city by 2050, introducing alternative energy forms of transportation is crucial.

The 19-meter-long IKA RERE ferry can carry up to 132 passengers on journeys across Wellington Harbour at an operational speed of 20 knots.It has been designed and built to complete one return run of 25 kilometres before charging dockside at a rate of one megawatt for 15 minutes while passengers disembark and board. The ferry will be charged from a 300-kilowatt charger at its overnight berth during its first year of operation.It is anticipated that the IKA RERE ferry will save approximately 640 tons of CO₂ annually compared to a similar-sized diesel alternative.

Leading New Zealand electrical company McKay acted as the project’s lead electrical designer and system integrator, choosing one of Danfoss’ Editron drivetrain systems to power the ferry. The system consists of two propulsion motors, two grid solutions for the AC network and six DC/DC converters connected to the vessel’s batteries. All of these components operate via a DC cabinet and are controlled via an electronic control system.

Erno Tenhunen, marine director of Danfoss’ Editron division, said:

“As companies, cities and countries around the world continue to set CO₂ reduction targets, the demand for zero-emission vessels and machines continues to grow. Our Editron marine system provides outstanding efficiencies within a power range of up to six megawatts. It is also compact and lightweight, enabling space and weight savings and increasing design freedom. These savings ultimately benefit passengers, as operators can provide a greater level of comfort.”

Jeremy Ward, managing director of East by West Ferries, commented:

“While IKA RERE has cost more than an equivalent-sized diesel boat, we will make savings back over time thanks to its cheaper running costs. The ferry’s electric motors, provided by Danfoss’ Editron division, require less maintenance than traditional diesel versions. The cost of charging the vessel’s batteries is also significantly less than filling it up with diesel.”

The IKA RERE ferry will complete survey sea trials before entering a commissioning stage with East by West Ferries. It will undertake a number of public sailings during the commissioning phase before being released into full service by the end of Q1 in 2022.