New load shedding stages for South Africa – this is what happens if we hit stage 16
National energy regulator Nersa has published the consultation document that will restructure load shedding in South Africa for public comment.
The document is titled the 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.
Once the document has gone through the necessary public consultations, it will be used to finalise what will be known as the NRS 048-9 Code of Practice Edition 3.
The public and other stakeholders have until 22 September to make submissions on the document, thereafter, comments will be collated and taken into consideration for the final decision on the proposals to be made.
It is important to note that Nersa has not yet formulated any opinions the key aspects of the draft NRS 048-9, Ed 3 that are raised in this consultation paper, but is raising them so that stakeholders can give their opinions and input on these issues to assist the regulator to make a well-considered decision.
However, it does detail the biggest change to load shedding – necessitated by record-levels of outages in 2023 with warnings that they could extend beyond the eight stages currently catered for in the standing code.
New load shedding stages
The key change in the document comes in extending load shedding stages to stage 16 – but the structure of the new stages may be unfamiliar to what most South Africans have become accustomed to.
At present, most South Africans understand each stage of load shedding to reflect 1,000MW of power that is removed from the grid.
However, under the proposed structure, this is rather expressed as the percentage of demand assumed by the System Operator at the time the stage is called. The percentages range from 5% of demand at stage 1 to 80% at stage 16.
While these percentages are in-line with the standing Code of Practice, the percentages in the standing code refer to a percentage “reduction in load profile of the national non-curtailment load” – not specifically demand.
The consultation paper also makes no mention of specific ranges (ie, +/- 1,000MW) as is the case in the standing code – although this may change in the final document.
“The specific reduction in load required to stabilize the system under a national supply constraint will be dictated by the power system conditions that prevail at the time,” Nersa said.
The proposed schedules also include the structure for customers who are part of the load curtailment programme.
The proposed stages are as follows:
| Stage | Reduction required through load shedding | Reduction required through curtailment |
| 1 | All stage 1 load scheduled by utilities 5% of demand | 10% reduction in normal demand profile |
| 2 | All stage 2 load scheduled by utilities 10% of demand | 10% reduction in normal demand profile |
| 3 | All stage 3 load scheduled by utilities 15% of demand | 15% reduction in normal demand profile |
| 4 | All stage 4 load scheduled by utilities 20% of demand | 20% reduction in normal demand profile |
| 5 | All stage 5 load scheduled by utilities 25% of demand | 30% reduction in normal demand profile |
| 6 | All stage 6 load scheduled by utilities 30% of demand | 30% reduction in normal demand profile |
| 7 | All stage 7 load scheduled by utilities 35% of demand | 40% reduction in normal demand profile |
| 8 | All stage 8 load scheduled by utilities 40% of demand | 40% reduction in normal demand profile |
| 9 | All stage 9 load scheduled by utilities 45% of demand | 50% reduction in normal demand profile |
| 10 | All stage 10 load scheduled by utilities 50% of demand | 50% reduction in normal demand profile |
| 11 | All stage 11 load scheduled by utilities 55% of demand | Reduction to essential loads or as instructed by SO |
| 12 | All stage 12 load scheduled by utilities 60% of demand | Reduction to essential loads or as instructed by SO |
| 13 | All stage 13 load scheduled by utilities 65% of demand | Reduction to essential loads or as instructed by SO |
| 14 | All stage 14 load scheduled by utilities 70% of demand | Reduction to essential loads or as instructed by SO |
| 15 | All stage 15 load scheduled by utilities 75% of demand | Reduction to essential loads or as instructed by SO |
| 16 | All stage 16 load scheduled by utilities 80% of demand | Reduction to essential loads or as instructed by SO |
According to the document, the responsibility for keeping the national electricity grid stable lies with the National Control Centre (NCC).
“If the NCC requires additional load reduction, utilities may assume this is in the best interest of the grid. The System Operator will undertake to understand, via network studies, the impact and management of the grid under lightly loaded conditions caused by high – above stage 8 – stages of load shedding,” it said.
What is the Code of Practice?
The NRS 048-9 Code of Practice is primarily an electricity utility-driven and executed document that derives its mandate and authority, once approved by the National Energy Regulator of South Africa (Nersa), as part of the Electricity Regulations Act.
The code that will soon come into effect is NRS 048-9, Edition 3.
When the first edition of the NRS048-9 code was established in 2010, load shedding stages were capped at Stage 4 – representing 25% of the base load – requiring utilities to “find” electricity load under emergency conditions.
The full consultation paper can be found here, or embedded below.
Written comments can be sent to [email protected] or hand-delivered to Kulawula House, 526 Madiba Street, Arcadia, Pretoria, 0083; or posted to PO Box 40343, Arcadia, 0007, Pretoria, South Africa.
The closing date for the submission of comments is 22 September 2023.
Read: New load shedding stages for South Africa coming soon – what to expect
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