In the Belgian North Sea, maintenance vessels are now able to tether to an automatic cable at a wind farm to get their batteries topped up. The innovative system is the first of its kind and a major step in keeping electric vessels as green as possible.

The charging system was deployed at Belgian's Nobelwind wind farm, which has been in operation since 2017 and features 50 turbines covering 19.8 square km (7.6 square miles) at sea. The facility is the third deployed by the Parkwind company and it supplies power to about 190,000 households.

Nobelwind's new charging station was shipped on a crew transfer vessel (CTV) 47 km (29 miles) offshore and its modular components were raised amongst the sea-based wind turbines using the facility's substation crane. Once it was established, the company successfully used it to charge up one of its CTVs. Parkwind reports that the transfer went off without a hitch, with no disruption to the facility's operation.

As you can see in the following video, which shows the system being tested with a land-based module earlier this year, the entire process is fully automated with no need for crew members to either connect or disconnect the charging tether, an innovation that adds to the system's safety factor.

"We are committed to making all of our activities as sustainable as possible and this is a game changer for our maintenance vessels, which can now access green energy directly from our wind turbines as they carry out their work," said Kristof Verlinden, head of operations and maintenance at Parkwind. "The trial proved the system can transfer electricity from a wind farm to the vessels safely without any disruption to the farm.”

Currently, the charging station can deliver up to 2 MW of power to CTVs and up to 8 MW of juice to the service operation vehicles (SOVs) that are responsible for maintaining the wind turbines. Parkwind says the system can also run the electrical systems of conventional vessels idling offshore to reduce their reliance on their diesel engines, thereby cutting emissions. You can see the system in operation at Nobelwind on Parkwind's Vimeo channel.

The recharging module was developed by Parkwind's partner, MJR, an offshore power and automation systems engineering company based in the UK. MJR is now studying the results of the Nobelwind deployment and using the findings to develop the world's first commercial offshore charging station, which is set to be deployed in early 2025.