A wind turbine nearly double the height of Nelson’s Column was toppled by too much wind after 50mph gusts caused it to “overspeed”, an investigation has found.
The 300ft structure crashed to the ground with its blades completely snapped at the £20 million Pant y Wal wind farm in Gilfach Goch, near Bridgend.
The incident prompted an urgent safety inquiry into the entire farm, as families living nearby described sounds of “thunder and lightning” before it fell on the morning of Monday, Feb 14.
An investigation by manufacturer Nordex found the collapse was caused by the turbine running in an “overspeed condition” for four hours.
A Nordex spokesman said: “A root cause analysis investigation determined that a technical issue, starting within an uninterruptible power supply cabinet for one of the blades, triggered an unprecedented chain of events in quick succession.
“This disabled the main power supply and the back-up power supply to each blade of the pitch system. Therefore all three blades of the wind turbine were left without power, resulting in a fixed state.
“The wind speed conditions on the day increased putting the wind turbine into an overspeed condition until it collapsed.”
Residents living near the wind farm told of their shock at the time of the collapse. The incident came in the same week Storms Dudley and Eunice caused chaos across the UK. Winds of 50mph are described on the Beaufort scale as a “strong gale”.
Lydia Stephens, who lives near the turbines, asked: “How the hell does a turbine fall over?” Villager Ricky Williams described it as “a bang like thunder early hours”.
One local resident said: “It was around 7am and fairly dark. My wife has stables about half a mile from the wind farm. She said she heard odd pulsing noises and then heard the crash about 30 minutes later.”
Residents likely to be ‘very worried’ about safety
The 10-turbine Pant y Wal wind farm opened in 2013 at a cost of £20 million, generating enough power for 18,000 homes – until one of them collapsed.
he incident raised safety concerns over other wind turbines across the Welsh valleys, prompting Nordex to inspect all the remaining turbines at Pant y Wal.
Speaking at the time, Rhodri Williams – an anti-wind farm campaigner who is part of Stop Y Bryn Onshore Wind Farm, that straddles Bridgend and Neath Port Talbot – said: “You can imagine if one of those comes crashing down, that it is not going to be too far away from peoples’ homes.
“We are pushing for the whole proposal to be scrapped, if not suspended, until a full independent investigation has taken place so we know the causes of this,” referring to the collapse at Pant y Wal.