Eskom and contractors at the Medupi power station had chosen not to allow workers to return to work on Thursday morning, following illegal protest action on Wednesday that disrupted bus transport to the site, resulting in the injury of 25 workers.

“We are not yet willing to risk the safety of our employees and, as such, workers have been locked out. We are certainly concerned about the violence observed yesterday,” Eskom spokesperson Hilary Joffe told Engineering News Online.

She said the power utility continued to engage with contractors to restore normal operations and emphasised that any labour disruption posed a serious threat to the project's tight schedule and could impact on Medupi's ability to meet its power generation deadline.

“It is a couple of days in the life of a seven-year project,” she said.

While worker grievances have been communicated, Eskom would not disclose the nature of these.

Wednesday’s protest primarily involved workers affiliated to the metals industries and the National Union of Metalworkers of South Africa (Numsa) who were employed by Hitachi and Murray & Roberts Projects, Joffe said.

As a result, Hitachi had locked out workers on Thursday morning and had not allowed other workers to return owing to safety concerns.

This followed protests on January 11 by some 1 100 workers employed by Alstom Kentz at Medupi, resulting in a lockout of those workers by Alstom Kentz.

“The safety of our people, and of those employed by our contractors, is a priority for Eskom. We are working with relevant parties, including the South African Police Service, to monitor and address the situation at Medupi and are investigating the circumstances around this incident,” Eskom said in a statement.

Medupi’s first unit is expected to generate first power to South Africa’s national grid by the end of this year.