For the first time, heavy-lift cargo drones are being used to speed maintenance operations at an offshore wind farm and reduce the safety risk to personnel and machinery. Ørsted, which had previously tested applications for drones, released a video showing a drone capable of lifting 70 kg (over 220 lbs) deployed at its Borssele 1 & 2 wind farm in the Dutch portion of the North Sea.
The drones that are being deployed are reported to be 70 kg units. Each has a wingspan of 2.6 meters (8.5 feet). They are larger and have more capacity than previous trials conducted by Ørsted. Last year, the company tested drones at the Hornsea 1 Offshore Wind Farm in the UK capable of lifting 150 lbs.
Borssele which is located about 14 miles off the coast of Zeeland near the Netherlands – Belgium border was fully commissioned in late 2020. At the time, the company said with its 94 turbines and 752 MW capacity, it was the largest in the Netherlands and the second-largest wind farm in operation.
Ørsted reports the current maintenance project called for updates to some critical evacuation and safety equipment in each of the turbines. The drone is lifting the critical equipment from an offshore supply vessel and in about four minutes carries it to the top of the nacelle.
The company says that its tests show the drones mean less work disturbance as wind turbines do not have to be shut down when the cargo is delivered. They also minimize the need to constantly reposition the support vessel to reach each turbine.
In the traditional system, the vessel would have had to sail to each turbine and using a crane lift the box containing the equipment to the transition piece on the turbine’s foundation. The box would then have to be lifted with the nacelle’s crane and then be moved to the top of the turbine. Ørsted said the operation could take up to six hours but through the use of drones, it has been able to complete the tasks at Borssele 10 to 15 times faster.
The company highlights that it continues to explore new technologies to enhance its offshore wind efforts. It has piloted a new technology that further optimizes offshore wind monopile installation. It is also deploying autonomous vessels for offshore surveying.
