The troubled Unit C3 at the Callide C power station outside Biloela is back online after repairs.
It follows an explosion in the plant on April 4 2025.
CS Energy said the generating unit would be safely and methodically returned to its full capacity in a staged manner after ramping up recently.
The unit’s return follows damage brought on when hardened ash detaching from the internal boiler wall resulted in a pressure spike within the furnace.
CS Energy acting chief executive officer Emma Roberts said about 100 people worked on rotating shifts six days a week on the C3 repairs, with approximately 31,000 hours worked.
“CS Energy, as operator, has introduced additional clinker safety controls based on our findings to date in relation to this incident,” Ms Roberts said.
“We have worked closely with Workplace Health and Safety Queensland to provide them with reassurance that there are sufficient controls in place to safely bring Unit C3 back online.
“The operations team has been rigorous in their approach and this is part of the cultural change the new board and management is fostering at CS Energy.”
CS Energy said the investigation into the C3 incident was continuing and that it would release its findings and response once complete.
CS Energy owns Callide C in a 50/50 joint venture with IG Power and operates Callide C on behalf of the JV.