CS Energy ran Callide C without a process safety team — then it exploded

In May 2021 the Callide C power station near Biloela, Queensland suffered a catastrophic explosion when the battery back-up system on its C4 unit failed. The blast put the unit offline and triggered the loss of power to almost half a million customers — the state's worst outage in decades. Workers described a two-tonne piece of metal shaft flying across the floor and a 300-kilogram gear launched 20 metres into the air.

CS Energy commissioned forensic engineer Dr Sean Brady of Brady Heywood to find out why. His draft report, released in June 2024, was damning: the key organisational factor was 'a failure to implement effective process safety practices' around the replacement of the new C4 battery charger. From April 2019 to July 2020 there was effectively no process safety team at all; the program was 'under-resourced and starved of funding'. The board's metrics tracked personal injury, plant availability and financial performance — not process safety.

The report also found 'competing tensions between cost reduction and process safety': a 2020 shareholder mandate weighing debt management equally with revenue constrained investment, a 50/50 joint venture with Genuity Group created competing asset priorities, and heavy turnover of key roles from 2017 made the safety focus harder to hold. The failures, it concluded, were 'not isolated incidents' but 'a symptom of an organisation's failure to value and implement effective process safety practices'.

Premier Steven Miles responded by moving to acquire 100% ownership of the Callide generators, appointing special advisors to the CS Energy board and ordering management plans for all the state's government-owned corporations. CS Energy called the released documents 'Dr Brady's draft opinions' and said it would publish the final report and its learnings.

Almost 500,000 Queensland customers lost power in the state's worst outage in decades; the unit was wrecked, and the government moved to take full ownership of the plant.

The process safety program was starved of funding and left without a team from April 2019 to July 2020.

The board's KPIs covered personal injury, plant availability and financials — major-accident risk was simply not measured.

A 2020 shareholder mandate prioritised cost cutting and debt management, creating 'competing tensions' with process safety.

Known weaknesses in management of change went unaddressed; the report called the explosion a symptom, not an isolated incident.

The 50/50 joint venture structure added competing asset-investment priorities and muddied accountability.

Process safety is invisible until it is the only thing that matters: a board tracking injuries, availability and finance — but not major-accident risk — is blind to the risks that end the business.

The June 2024 release covered draft reports; CS Energy committed to publishing the final Brady Heywood report along with its learnings and to working with the government on recommendations. The Queensland government appointed special advisors to the board, directed every government-owned corporation to produce detailed asset management plans, and launched a review of the publicly owned generation businesses, alongside the push to buy out Genuity Group's half of Callide C. The opposition called it 'one of the greatest scandals we've seen in this state for a long, long time'.