Wind turbine collapses at Point Tupper Wind Farm after hub bearing fault, Nova Scotia

An 80-metre wind turbine at the Point Tupper Wind Farm in Point Tupper, Nova Scotia, operated by Renewable Energy Services, collapsed on 17 August 2016 after its blades struck the tower, bending it before it buckled at the midpoint and fell to the ground. The turbine's hub had suffered a bearing failure months earlier and had recently been repaired, with the hub replaced and blades reattached. During a lightning-protection system test, a technician heard an unusual noise, suspected to be a forgotten washer inside the hub, and on inspection found the blades were incorrectly pitched and the electromechanical brake had not engaged. Workers were instructed to leave the turbine and move to a safe distance. Around four hours later, with no one present, the tower collapsed. No injuries, fires or explosions occurred, and the wider power grid was unaffected. A provincial stop-work order was issued and lifted four months later once the manufacturer, Enercon Canada, had responded to regulatory queries.

A prior bearing failure in the hub required replacement and blade reattachment; technical challenges were encountered during this repair; the electromechanical brake was not applied and the blades were left pitched incorrectly (about 2 degrees instead of 90 degrees) during a lightning-protection test, which appears to have led to the structural failure.

1. Component replacement and reassembly work following a bearing failure should be independently verified before returning a turbine to service, including confirmation of correct blade pitch and brake engagement.
2. Unusual noises or loose components identified during maintenance should trigger an immediate stop-work and full inspection rather than continued operation.
3. Clear evacuation protocols and safe-distance procedures, as demonstrated here, can prevent injuries even when a structural failure becomes imminent.

cbc.ca/news/canada/nova-scotia/forgotten-washer-heard-in-hub-be...