Eskom employees affiliated to three unions locked in wage talks have embarked on strike action over bonuses.
The power utility is warning of possible load-shedding this week.
There have been reports of acts of intimidation at several plants and power stations.
Wage talks between Eskom and unions have been ongoing for almost a month now.
People are advised to use electricity sparingly and to be aware of load-shedding schedules.
Information can be found on Eskom’s and local municipality websites.