Eskom says there is a high risk of load shedding from 17:00 to 21:00 as the power system is severely constrained.
Issuing a Stage 1 load shedding alert, Eskom said "the power system is expected to be severely constrained this evening from 5pm to 9pm, with a high risk of load shedding”.
Eskom said that while it did not implement rotational load shedding on Tuesday morning, an alert for rotational load shedding for up to four hours may be necessary due to a shortage of capacity.
"Level 1 load shedding requires 1000MW to be load-shed nationwide. Load shedding is conducted as a measure of last resort to protect the power system from a total collapse or blackout," the power utility said.
The power utility first implemented load shedding on Thursday, following the disruption to supply caused by the workers’ demonstration.
Workers at power plants had abandoned their work posts amid intimidation and violence by fellow workers who are demanding wage increases.
The pickets led to interruptions in the power supply, forcing the firm to implement load shedding – the first since 2015.
The company had earlier said the supply system was starting to stabilise, after experiencing a “significant increase in plant outages and bottlenecks in routine maintenance” because of a lack of resources to operate plants optimally.
The state-owned power utility had expected that the full restoration of electricity supply would take up to 10 days, raising the possibility of blackouts.
Talks to resolve the wage increase impasse are underway in Johannesburg.
Workers are demanding pay increases of between 9% to 15%. Eskom says it is unable to grant the increases due to dire financial challenges.
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