They’re becoming an increasingly common sight on the horizon – giant turbines towering imperiously over open countryside as wind power is embraced as an effective alternative to fossil fuels.

But wind turbines need regular maintenance. They are exposed to extreme conditions including lightning, UV radiation, snow, hail, and storms, which can damage them and affect their performance.

Periodic inspections are essential to ensure their structural integrity and smooth operation. For years, those checks relied upon people using binoculars and long-range cameras from the ground combined with technicians working at height.

To make the inspections more effective and to reduce safety risks, CLP China is switching to a flying squad of drones and blade robots to keep its wind turbines turning.

Scaling new heights

The robot inspections were put to the test at Qian’an Wind Farm in Jilin province. The wind farm has been in operation for more than a decade and its 11 wind turbines and seven kilometres of power transmission lines are around midway through their expected life span.

In January, two drones weighing 1.38 kg and 6.3 kg took off in temperatures of -20°C to get an up-close look at the wind turbines.

As well as landing carefully on the turbines, the drones took high-definition photos and video of turbines parts including the tower, the nacelle, and even the edge and tips of the blades.