The anticipated Brady Heywood investigative report into the catastrophic explosion at Callide C power station in May 2021 has found state-owned CS Energy failed to implement “effective process safety practices” at the facility.
CS Energy commissioned Dr Sean Brady of forensic engineering firm Brady Heywood to review the underlying cause of the 2021 explosion that resulted in major damage to Unit C4, which remains offline.
There were no fatalities, but the incident destroyed Unit C4’s turbine generator and destabilised the Queensland power grid. The explosion initiated a cascading failure of nine major generator units across the state, which caused almost half a million Queensland customers to lose power.
In February, CS Energy released its own report on the technical contributing factors to the Callide Unit C4 incident, saying the explosion was caused by the failure of a battery back-up system at the power station’s C4 unit.
Related article: Callide C4 incident “could not have been anticipated”
CS Energy’s analysis found that the Unit C4 incident was the result of the simultaneous failure of key electrical equipment and system backups in a series of complex events, which it said “could not have been anticipated”.
However, the Brady Heywood report said the key organisational factor that contributed to the incident was a “failure to implement effective process safety practices that would have increased the likelihood of identifying and managing the risks associated with replacing the new Unit C4 battery charger and bringing it into service”.
The Brady Heywood investigation into the causes of the incident was undertaken in two parts: a technical investigation and an organisational investigation. The technical investigation examined the technical causes of the incident, and the organisational investigation examined the organisational factors related to the incident.
CS Energy CEO Darren Busine, who was appointed in July 2023, said the business had continued to take action since the two incidents to progressively improve safety for its people and plant at Callide and its other assets across the state.
“The action plan we are releasing today summarises our actions to date, as well as those underway, to build a safer, better CS Energy,” Busine said.
“Brady Heywood’s technical findings are consistent with CS Energy’s technical report released in February this year.
“Whilst on our reading of the Brady Heywood Report, a lack of maintenance did not cause the incident, we clearly have areas of improvement to ensure we operate and maintain our assets to world class standards.
“The Brady Heywood Report found that more effective process safety practices could have assisted CS Energy in identifying and managing the risks associated with bringing the C4 battery charger into service.”
Busine said CS Energy was committed to becoming a safer, better business.
“There is nothing more important than safety. Our action plan sets out how we will improve our capability to assess, mitigate and control the process safety risks inherent in owning and operating power generation assets,” he said.
“In addition, an Independent Advisory Group, chaired by Adjunct Associate Professor Trevor Love and comprising leading experts in process safety and organisational design, has been established to oversee and support us in executing and updating the plan.
“We are committed to learning from these events and giving our people better systems and tools so that they can do their jobs safely.”
Premier Steven Miles said the Queensland Government would be taking steps to “achieve 100% ownership of the Callide generators”.
“One of the causes Brady points to in his report is confusion over management structures because of that complicated joint venture arrangement, so 100% public ownership is what we think will assist there,” he said.
Related article: Callide C return-to-service date pushed back again
He the government would appoint special advisors to the board of the state-owned corporation “to ensure the government has more direct influence over the direction and to ensure that it has appropriate governance”.
Callide Power Station is comprised of two power plants—Callide B and C—each with two generating units (B1 and B2, C3 and C4).
Callide Energy Pty Ltd owns Callide C in a 50/50 joint venture with IG Power. CS Energy operates Callide C on behalf of the JV.
CS Energy owns 100% of the neighbouring Callide B Power Station.
