Second Callide Power Station unit back online about a month after mass blackout event affected Redlands, Logan

A total of 387,000 customers across the region were without power during the outage peak, with the fire knocking out about 10 percent of the state's power capacity.

More than 15,000 Redlands and Logan residents were in the throes of a blackout as of 3.15pm on Tuesday, May 25, as crews worked to repair mass outages.

Two of the plant's units are functioning again after B2 was brought back online about midday yesterday.

It means two of the four units are now back in service.

Springwood MP and Energy Minister Mick de Brenni said the focus was now on the C3 unit, which was likely to be brought back online next month.

"The return of unit B2 is another important milestone for the Callide workforce and community," he said.

"It is an incredible achievement and testament to the professionalism of CS Energy employees and contractors, that this has been done so safely and quickly.

"Like we saw with unit B1 last week, B2's output will be safely and gradually ramped up to its full capacity over the next 48 hours."

The power station fire broke out in the turbine hall about 1.45pm, causing three units in operation at the time to go offline.

The plant was evacuated and emergency services called.

Power was restored to most customers within a couple of hours but households were urged to cut power use in the aftermath to minimise stress on the system.

Mr de Brenni said the safety of the station's workforce remained a top priority.

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