Johannesburg - Eskom declared a power "emergency" on Sunday and told large industrial users to cut their consumption by up to 10% to ease pressure on the strained national grid.
The declaration is on top of two days of rolling blackouts, and was caused by generators producing 1 700 MW of power at two plants tripping out, Eskom said.
"Eskom has declared a power emergency with large industrial customers, requiring them to urgently reduce their electricity usage by 10% from 15:00 to 20:00 today," Eskom said in a statement.
"The declaration of a power emergency follows in addition to the implementation of stage two of load shedding earlier today [Sunday]."
The power system experienced an increase in demand due to weather conditions and increased load losses as a result of multiple tripping of generating units at the Majuba and Matimba power stations.
"Eskom has lost a total of 1700 MW of generating power," the power utility said.
"Eskom is now following the protocol in terms of its emergency procedures in order to secure the power system."
Due to loss of additional generating capacity, Eskom implemented stage two load shedding at noon on Sunday and this would continue until 22:00 on Sunday evening.
"The risk of load shedding for tomorrow [Monday] and Tuesday is medium to low. This is owing to steady progress made in building reserves to limit the risk of load shedding next week," Eskom said.
"Eskom calls on all electricity users to urgently switch off geysers, pool pumps and all non-essential appliances in order to allow the power system to recover.
Read: Eskom worries grow amid load shedding
On Sunday, Sapa reported that Eskom was concerned about its diesel reserves which could affect electricity supply.
"We have a certain amount of diesel, but not full capacity," spokesperson Andrew Etzinger said.
"If we need to run the... open gas turbines hard in the first few days of the week we will deplete [our reserves]."
He said the system was expected to be tight in the early part of the week but no rolling blackouts were scheduled.
- Reuters, Sapa
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