Eskom has confirmed that a generator of Unit 4 of the Medupi power plant exploded on Sunday night, which caused Unit 5 to trip.
Eskom confirms explosion

Eskom on Monday confirmed that the Medupi power station experienced an explosion at the unit 4 generator.

The incident occurred at about 10.50pm on Sunday and is suspected to have resulted in unit 5 tripping, said the utility.

The explosion resulted in extensive damage to the generator, it said. “The incident occurred during the activity to displace hydrogen with carbon dioxide and air respectively, for the purposes of finding an external leak.”

No injuries have been reported and all employees and contractors have been accounted for. Emergency services attended to seven colleagues requiring treatment for shock.

“Following the power station preliminary investigation, it appears that while performing this activity air was introduced into the generator at a point where hydrogen was still present in the generator at sufficient quantities to create an explosive mixture, which ignited and resulted in the explosion. It also appears that there was a deviation from the procedure for carrying out this activity.

“As such Eskom has undertaken to place those employees who were responsible to manage and execute this work under precautionary suspension pending the conclusion of the Major Event Investigation,” Eskom said.

Unit 4 had been on a short-term outage since August 6.

All work on the unit was suspended with immediate effect. This included the suspension of all permits to work on the plant until further notice.

“Preparation for the return to service of Medupi unit 5 is currently in progress.