Engie booked a €714m ($773m) impairment charge last year due to operational issues with Nordex-made wind turbines on an onshore US wind farm.

The French energy group posted a strong overall profit for the year, but also revealed a €1.32bn impairment.

About $784m was described as losses on property, plant and equipment on renewable energy production assets, and most of this was in North America where it was “due to very specific operational difficulties linked to turbine performance on a wind power asset.”