New Eskom load-shedding stages coming soon
Hanno Labuschagne
The National Energy Regulator of South Africa (Nersa) is expected to reveal changes to Eskom’s load-shedding stages in the coming weeks.
The regulator published a consultation document detailing a planned revised load-shedding approach that allows for up to stage 16 power cuts in August 2023.
The document, NRS 048-9 Electricity Supply – Quality of Supply: Code of Practice – Load reduction practices, system restoration practices, and critical load and essential load requirements under system emergencies, was opened for public comment on 11 August 2023.
The finalised NRS 048-9 Code of Practice Edition 3 will replace the current edition of the code Eskom’s System Operator uses to define load-shedding stages.
In addition to enabling the power utility to implement higher stages of power cuts, the draft document proposes allowing the System Operator to instruct distributors to reduce demand based on a percentage of the country’s national non-curtailment load at a given time.
The current rules only explicitly make provision for load-shedding up to stage 8.
If the revision proposed in the consultation document is approved in its current form, the System Operator will be able to instruct that electricity demand be dropped by between 5% and 80% of the total load, from stage 1 to stage 16.
The table below shows how much demand distributors or heavy electricity users will have to shave off their total load through load-shedding or load curtailment, respectively.
Proposed demand reductions under NRS 048-9 Electricity Supply Edition 3 | ||
Stage | Reduction through load-shedding | Reduction through load curtailment |
1 | 5% of demand | 10% reduction in normal demand profile |
2 | 10% of demand | 10% reduction in normal demand profile |
3 | 15% of demand | 15% reduction in normal demand profile |
4 | 20% of demand | 20% reduction in normal demand profile |
5 | 25% of demand | 30% reduction in normal demand profile |
6 | 30% of demand | 30% reduction in normal demand profile |
7 | 35% of demand | 40% reduction in normal demand profile |
8 | 40% of demand | 40% reduction in normal demand profile |
9 | 45% of demand | 50% reduction in normal demand profile |
10 | 50% of demand | 50% reduction in normal demand profile |
11 | 55% of demand | Reduction to essential loads or as instructed by System Operator |
12 | 60% of demand | Reduction to essential loads or as instructed by System Operator |
13 | 65% of demand | Reduction to essential loads or as instructed by System Operator |
14 | 70% of demand | Reduction to essential loads or as instructed by System Operator |
15 | 75% of demand | Reduction to essential loads or as instructed by System Operator |
16 | 80% of demand | Reduction to essential loads or as instructed by System Operator |
MyBroadband asked Nersa for comment on when the new load-shedding rules will be finalised, but it did not provide feedback by the time of publication.
However, the regulator published an estimated timeline to complete the process alongside its original consultation paper.
It estimated that it would take 77 working days — or about four calendar months — to complete the approval of the document from the development of the consultation paper.
That period included nine working days before the publication of the consultation paper.
Based on these timelines, the regulator should have finalised the document sometime in December 2023.
In the absence of further notice from Nersa, it is reasonable to expect that the new rules should be published soon.
The screenshot below shows the timeline as set out in the consultation paper.
MyBroadband has calculated the megawatts that must be shed from the grid under the new stages of load-shedding under high-demand and low-demand scenarios.
The table below shows how much demand could theoretically be cut from demand under the proposed load-shedding stages.
Theoretical MW reductions under proposed load-shedding stages | ||
Stage | Low demand scenario: 23,000-24,000MW | High demand scenario: 30,000-32,000MW load |
1 | 1,150–1,200MW | 1,500–1,600MW |
2 | 2,300–2,400MW | 3,000–3,200MW |
3 | 3,450–3,600MW | 4,500–4,800MW |
4 | 4,600–4,800MW | 6,000–6,400MW |
5 | 5,750–6,000MW | 7,500–8,000MW |
6 | 6,900MW–7,200MW | 9,000–9,600MW |
7 | 8,050–8,400MW | 10,500–11,200MW |
8 | 9,200–9,600MW | 12,000–12,800MW |
9 | 10,350–10,800MW | 13,500–14,400MW |
10 | 11,500–12,000MW | 15,000–16,000MW |
11 | 12,650–13,200MW | 16,500–17,600MW |
12 | 13,800–14,400MW | 18,000–19,200MW |
13 | 14,950–15,600MW | 10,725–20,800MW |
14 | 16,100–16,800MW | 21,000–22,400MW |
15 | 17,250–18,000MW | 22,500–24,000MW |
16 | 18,400–19,200MW | 24,000–25,600MW |