As Eskom is reviewing the loadshedding framework to prepare for the prospect of higher stages of loadshedding in future, specifications developer NRS Association of South Africa has assured the public that this is primarily a proactive measure to enable the utility and municipalities to be ready to respond should it be necessary.

Engineering News last week quoted Eskom acting generation executive Thomas Conradie as saying that a review of the loadshedding framework was under way to prepare for the prospect of higher stages of loadshedding – potentially up to Stage 16 – in future.

By proactively planning and preparing for loadshedding up to and including at possible elevated levels, NRS believes the propensity for errors, if any, to creep in by the system operator – Eskom – at significantly higher loadshedding stages can be reasonably and acceptably mitigated to a minimum.

In this respect, NRS and the National Energy Regulator of South Africa (Nersa) are developing an NRS 048-9 Edition 3 Code of Practice (CoP) as a matter of priority.

This latest CoP, and its predecessors, are electricity-utility-driven and executed CoPs, and derives its mandate and authority after it has gone through various processes. The NRS CoPs are meant to help rationalise and guide technology standardisation, including to describe a predetermined plan for switching off parts of the electricity network in stages.

The CoPs address not only the power system requirement in terms of load reduction, but also how it is done and communicated to the public to ensure the least negative impact on critical infrastructure. The CoPs offer a structured way for utilities to respond to the National Control Centre’s instruction to reduce load.

NRS highlights that the NRS 048-9 code must in no way be construed as a CoP that is driven by any single stakeholder, such as Eskom or municipalities, nor can it designate special sectors in respect of load reduction.

While the NRS 048-9 CoP provides for an ordered and consistent approach to emergency load reduction, it does not subrogate any actions that system operator Eskom may deem necessary in real-time to ensure the security of the national power system, in terms of its compliance to the Grid Code, among others, to prevent a national blackout.

The current loadshedding or load reduction practices, system restoration practices and critical load and essential load requirements under power system emergencies are regulated by Nersa’s CoP called NRS 048-9 Edition 2, which documents and regulates loadshedding up to Stage 8.

Its predecessor, NRS 048-9 Edition 1, regulates loadshedding up to Stage 4 of loadshedding.

The CoPs aim to strike a balance between an equitable distribution of burdens caused by an electricity shortage, avoiding the catastrophic consequences of a blackout and the impact of loadshedding on essential loads and critical loads.

Since Eskom’s coal-fired power generation fleet has deteriorated to a level which may necessitate higher levels of loadshedding, the NRS deemed it prudent to start revising the NRS 048-9 Edition 2 CoP.

Edition 3 of the CoP will include proactive measure planning and associated risk mitigation measures to successfully implement loadshedding stages beyond Stage 8, it says.

NRS has assured the public, firstly, that the Edition 3 CoP is being developed through extensive consultation and deliberation by those who are fully cognisant of the technical and practical constraints of the distribution network.

The association has also assured that only once the management committee of the NRS has considered and finally approved the NRS 048-9 Edition 3, with input from various stakeholders, can this CoP document be approved by Nersa, following all its internal processes, including public consultation.  

Therefore, NRS itself undertakes a consultative process to devise the revisions to the CoP, while Nersa will undertake a wider public consultative process.

NRS explains that Nersa will become the owner of the CoP once it is finally approved and released.

NRS’s membership comprises eight metropolitan municipalities, the Association of Municipal Electricity Utilities of Southern Africa, the South African Bureau of Standards, Nersa and Eskom as members.

Ultimately, the finalised NRS 048-9 Edition 3 CoP will provide a methodology for Eskom to reduce the whole load base in a structured way.