Johannesburg - Most workers reported for work on Thursday at Medupi power station, Eskom said.
"Despite this being a payday weekend where Eskom has an agreement with workers to take time off and run their errands, most of them are back at work following yesterday's [Wednesday] protests," said spokesperson Hilary Joffe.
On Wednesday, a group of between 500 and 1 000 workers protested at the power station, which is under construction.
Eskom said the protest turned violent with stones thrown and two vehicles damaged. No one was injured.
The protest was related to dissatisfaction with one of the allowances workers received, which was currently the subject of negotiation.
Joffe said members of Parliament's energy portfolio committee were continuing their inspection of the station after being disrupted by the protesting workers on Wednesday.
The Medupi power station is a new, dry-cooled, coal-fired power station being built by Eskom near Lephalale in Limpopo.
Two weeks ago, Eskom said in a statement the new power station would probably begin contributing to the national grid only in the second half of next year because of construction problems. The previous target was December.
Public Enterprises Minister Malusi Gigaba insisted earlier this year that the December deadline would not change.