Electric Ferry

Our Customer was experiencing serious issues with their vessel charging and power utilisation meaning that, on long journeys, they were not able to return to port on battery power alone. Consequently, they were having to use diesel generators to provide enough additional power to get back to the quayside.

Nøste performed a power quality survey on the ferry and on the shore power charging station, quickly establishing that the level of voltage and current harmonics being generated were far higher than design limits, degrading the rapid charging capability and causing accelerated ageing of the batteries. In additional, due the losses caused by these high THDs, the system was not able to charge at the rated current, instead having to be charged at a reduced amperage.

Ezone Energy’s innovative p1™ isolation transformer was installed on the quayside and, together with changes being made to the grounding of the Protected Earth, the post installation survey confirmed a 22% reduction in reactive power, an improvement in current balance and a significant reduction in PE current.

Our next steps will be to install 2x Ezone p1™ transformers on board the ferry to eliminate the harmonics previously noted and to restore the operation of the ferry, during both charging and voyages, to the as-built specifications.

Our customer foresees substantial savings in energy (fuel and electricity) costs as well as reduced operating costs from an improvement in equipment reliability.