This comes as Eskom has failed to regain control of its failing coal fleet, after unplanned breakages led to unprecedented Stage 6 load shedding on December 9. Over the festive period unplanned outages remained consistently above 12 000 megawatts (MW) – much higher than the 9 500-MW limit set by Eskom to keep the lights on. Over the past weekend it once again rose almost 16 000 MW, resulting in Stage 2 load shedding despite low demand.

This has led to fears of much more regular and intensive load shedding once the economy gets going by January 13.

Eskom is asking the High Court in Pretoria to review and set aside part of Nersa’s decision to limit its revenue from electricity tariffs for the period 2019/20 to 2021/22, the fourth multi-year price determination (MYPD4), and allow it to recover R69 billion additional revenue over the next two years.

The urgent part of the challenge is limited to the R69 billion that Nersa deducted from Eskom’s allowable revenue, in light of the equity injection of R23 billion that government promised the utility in each of the three years of the MYPD4 tariff period.

Read: Eskom wants R27bn clawback from consumers

Eskom CFO Calib Cassim told the court in his founding affidavit that this move is irrational and should be reversed or it will cause Eskom and the whole economy irreparable harm.

Eskom has indicated that it will at a later stage also challenge the rest of the Nersa decision, but has not yet submitted court papers in this regard.

It is however also challenging four more Nersa tariff decisions in two other applications that are set to be heard at the end of this month and the end of February respectively.