South Africa’s state-owned power utility Eskom has refuted claims circulated by media outlets that it has been burning excessive amounts of diesel to avert power outages, locally called load shedding, in the run-up to the May 29 general elections.

South Africans have recently enjoyed more than 40 continuous days without load shedding, which had been an almost daily disruption for businesses and households over the past year.

However, rumours have started to spread that Eskom was burning emergency diesel reserves to power its open-cycle gas turbines (OCGTs) to create an illusion of constant power supply -- a claim that the power utility denies.

According to former Eskom CEO André de Ruyter, the temporary relief from load shedding was owing to Eskom’s burning diesel at a “rate of knots,” News24 reported.

De Ruyter, who resigned from Eskom in December 2022, is now a senior fellow at the Yale Jackson School of Global Affairs in the US. He was a guest speaker at the Southern African financial services group PSG’s annual conference on May 8.

De Ruyter claimed that during his time at Eskom, he and former chief operating officer (COO) Jan Oberholzer had spent only about ZAR6bn ($326mn) a year on diesel to run the utility’s OCGTs in order to generate power.

“We were very aware of how we had to scrimp and save to use the diesel very frugally and very carefully,” he said. “The budget for this year for diesel is ZAR24bn. That’s four times what we had at our disposal, so if the lights are on, well done, but they’re on because we are pouring money into diesel at a rate of knots,” De Ruyter added.

Claims contested

Minister in the Presidency responsible for Electricity, Kgosientsho Ramokgopa, recently publicly denied that the longest streak without load shedding since the pandemic was due to burning more diesel. He said Eskom burned far less diesel in April, compared to last year.

Ramokgopa attributed this improved performance of Eskom’s power generation fleet to timely planned maintenance at its power plants carried out during recent months. The minister also claimed that the end of crippling power outages was “within touching distance,” as reported by NewsBase.

In a statement late on Friday (May 10), the power utility said that load shedding remained suspended owing to sufficient generation capacity, resulting from a more reliable generation fleet. Eskom also claimed the continued sustained improvement in generation performance and a 4,400MW reduction in unplanned outages.

Eskom has also hit back at speculations that it is burning diesel excessively to power its OCGTs and avoid load shedding. “Contrary to media reports and speculations, Eskom’s utilisation of OCGTs is closely monitored, and their role is strategic rather than extensive,” the utility said.

According to Eskom, the utility spent significantly less on diesel to run its OCGTs last month than at the same time a year ago. “In April 2024, Eskom spent ZAR1.1bn on OCGTs, producing 167.8GWh,” it stated. “This is about 60% less than April 2023 when ZAR3.1bn was spent to produce 470.22GWh.”

In addition, Eskom said the OCGT load factor for April 2024 decreased significantly to 6.8% compared to last year’s figure of 19.13% in the same month.

Pre-election power play

However, a statement put out by the Democratic Alliance (DA) opposition party just a few hours earlier on Friday alleged that the National Energy Regulator of South Africa (Nersa) had “confirmed that Eskom is rapidly depleting its diesel budget for 2024/2025 financial year at an alarming rate.”

The DA also claimed that, based on a report in the weekly newspaper Mail & Guardian, Eskom had already blown more than its quarterly budget of diesel for the first quarter of this financial year in just one month. This was linked to political pressure related to the upcoming elections, the DA stated.

“The DA will be submitting an official Public Protector complaint against the Ramaphosa administration based on prima facie evidence that it overstepped its authority and directly interfered in the operation of Eskom for political advantage in an election year,” DA Shadow Minister of Public Enterprises Mimmy Gondwe MP said in the statement.

“In addition, we will make the case that they deliberately used false information to mislead members of the public on Eskom’s diesel use because they wanted to cover up their political scheme.”

Gondwe further added that chances were high that load shedding would return almost immediately when polls close on 29 May.

“The manipulation of load shedding to influence an election outcome is an eggragious violation of the law and the ANC government, together with Eskom executives that they are working with, must be held accountable,” she said. “South Africans should not be fooled by this brazen abuse of power and they must act to decisively vote out the manipulators on the 29th of May.”

While Eskom had confirmed that its OCGT usage in April 2024 was near the claimed amount in capacity, it denied this has resulted in its budget for diesel being exceeded.

“Eskom’s budget for diesel in the current financial quarter (April to June 2024) is ZAR5.8 bn, and ZAR1.16bn has been spent as of 9 May 2024,” the utility said.

Nersa subsequently also released a statement criticising the Mail & Guardian report. Much of its comment on the matter aligned with Eskom’s, and it denied blaming the decreased load shedding on the utility burning more diesel, a local news outlet MyBroadband reported.

“Nersa distances itself and condemns in the strongest possible terms the incorrect and misleading article published by the Mail & Guardian,” the regulator said.

Support for Eskom

While it seems logical to believe that the ruling African National Congress (ANC) party is forcing Eskom to burn more diesel to keep the lights on and boost its chances at the polls, energy analysts say the data doesn’t support this.

It is true that the governing party’s election prospects are closely linked to Eskom’s performance. However, local energy experts determined that there was no foul play involved.

According to Chris Yelland, numbers indicate that while diesel use was very high in the first 12 weeks of 2024, it declined sharply when load shedding was suspended.

The reason behind it is simple, explains energy policy consultant Nick Hedley. In late March, electricity supply finally caught up with demand. “So we’re now using diesel-powered turbines for their stated purpose – to help meet surges in demand during the evening peak periods, rather than running them almost constantly to limit load shedding.”

At the same time, the rest of the coal fleet appears to have stabilised somewhat after maintenance was ramped up to respectable levels over the summer months, Hedley says.

Additionally, Eskom reckons a cumulative 5.5 GW of solar has now been installed on the rooftops of the country’s malls, office blocks, warehouses and households – with an impressive 2.1 GW added over the past 12 months alone.

According to an independent energy research group Ember’s estimates, installed solar systems accounted for a record 10.4% of South Africa’s electricity mix in February.

The resultant decline in day-time grid demand has helped to trim Eskom's diesel requirements and is allowing the utility to replenish its pumped storage dams, which can then discharge energy when needed.

All things considered, South Africa’s electricity system is the healthiest it’s been in a while, Hedley concludes.