Ørsted has for the first time deployed heavy-lift cargo drones at the Borssele 1 and 2 offshore wind farms in the Dutch North Sea.

The 70-kg drones, with a wingspan of 2.6 m, are transporting cargo of up to 100 kg from a vessel to all 94 wind turbines.

Ørsted first tested the concept last year at the Hornsea 1 wind farm in the UK southern North Sea.

For this new campaign, the company is updating certain evacuation and safety equipment items in each of the turbines.

Typically for this operation, a vessel would sail from one wind turbine to the next, using a crane to lift each box containing the equipment onto the transition piece. The box would then be lifted using the nacelle’s crane to reach the nacelle and finally moved to the top of the turbine.

At Borssele, however, the drones will fly back and forth from an offshore supply vessel directly to the top of the nacelle, an operation that takes about 4 minutes compared to about 6 hours under the conventional approach.

Ørsted calculates it has been able to complete the tasks at Borssele 10 to 15 times faster than before, taking into account transport to and from the shore. So it expects the use of drones to deliver cargo to Borssele 1 and 2 to cut costs as well as improving operational safety and efficiency.

Drones cause reduced work disturbance, the company added, as wind turbines do not have to be shut down when the cargo is delivered.

Plus, they limit risk, making it safer for the personnel working on the wind farm, and minimize the need for multiple journeys by ship.