Electric ferries are quickly becoming a reality and need safe and reliable technology for efficient commercial operations.

One of the main challenges for any electric vessel is how to charge safely and quickly without delays. Instant charging has therefore long been on shipowners’ wish lists.

Smart technology company Wärtsilä has used ground-breaking research from SINTEF Energy Research to develop a wireless, inductive charging system.

The system transfers energy through an electromagnetic field instead of using traditional cables, and works from a distance of up to half a metre. This means ships can connect to a power source almost instantaneously, even before they have ready docked.

The current version of the charger has a capacity of about 2.5MW as a single unit, which is 500 times greater than the daily power consumption for a normal Norwegian household. Higher capacity can be achieved with larger units or parallel systems.

The wireless system prevents wear and tear on cables and plugs – and improves operational safety – as there is no physical connection between ship and shore. The automatic connection also makes better use of available docking time than other systems.

The system is fully enclosed and thus not exposed to the environment. This makes it highly reliable and limits the need for maintenance.

Since September 2017, Wärtsilä has successfully tested its wireless charger on the hybrid ferry Folgefonn in Western Norway. The ship is the world first’s commercial ferry to use a wireless charger.

With electric vessels becoming increasingly common, efficient charging methods will be crucial.

Because the induction charger is suitable for any battery-powered technology needing a quick and flexible charging system, its areas of application extend beyond the ocean industries as well.