The National Rationalised Specifications (NRS) Association of South Africa says that the new load shedding stages for the country are still being finalised.
Briefing the National Press Club on blackout mitigation measures on Wednesday (21 June), NRS chairperson Vally Padayachee repeated and stressed points raised around the new schedules in the past few months.
He said the revised load shedding document – known formally as NRS 048-9 Edition 3 – needs to attain 100% consensus from the Work Group before it can be sent to energy regulator Nersa for legal mandating.
The document should be presented to Nersa “in the next few days”, he said.
Padayachee stressed that the revised stages – which will now go up to stage 16 load shedding – were a proactive measure, given the state of the Eskom grid, but not an indication that the country will ever reach those levels of outages.
Ultimately, the new load shedding specifications differ from previous versions by splitting the entire power baseload into load shedding stages.
The first edition of the rules only split a quarter (25%) of the base load (up to stage 4) and the second edition split half (50%) of the baseload (up to stage 8).
With the full base load divvied up, the new specifications will drop various contingency plans and processes that were included to deal with what happens past stage 8 load shedding.
“It is very important also that higher stages of load shedding does not mean we get closer to a blackout,” he said.
“The need to plan for a potential load shedding stage 8 – up to and including load shedding at possible elevated levels and the unlikely event up to Stage 16 – is primarily a proactive measure.”
Just because stage 16 will exist doesn’t mean the country will get there, he said.
Some changes being introduced in the new edition include:
- Splitting the base load into 16 blocks (ie, stage 16 load shedding)
- Changing the definitions for load curtailment customers, including ‘strategic curtailment customers’
- Introducing a lot more freedom around load curtailment for utilities
How the load shedding specifications work
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.
According to the NRS, ‘finding’ electricity with 75% of the load not being used was reasonably straightforward. However, attempting to do so beyond Stage 4 was not easy.
The need for Stage 6 load shedding in 2019 prompted the NRS 048-9 Work Group to consider extending the load shedding stages to manage load shedding to Stage 8 (Edition 2).
In stage 8 half the electricity load is shed, and the other half is waiting to be shed, it said. Under these conditions, it is generally much harder to “find” electricity load, it said.
Given the deterioration of Eskom’s grid and energy availability, it has now become prudent to plan even further ahead.
The group said the final NRS 048-9 Edition 3 will now provide a methodology for utilities to reduce the whole load base in a structured way. Ostensibly, this would provide for 16 stages of load shedding – although the final picture could look very different with other changes under consideration.
This also means that contingency plans for the unknown – ie, “what happens beyond stage 8” – can be dropped.