Eskom has been using diesel-fuelled auxiliary turbines extensively to stave off power cuts in South Africa following delays in restoring some generation capacity.

The utility fired up the units after 2 685 megawatts of capacity failed to return to service on September 23 as planned, Eskom said in a reply to questions. “Additionally, higher-than-expected electricity demand driven by cold weather has contributed to this situation,” it said.

While Eskom has been lauded for preventing rolling blackouts for more than six straight months, plant outages have led to “extensive usage” of the so-called open-cycle gas turbines intended to run during peak demand.

The utility used more power from the units in September than it did during the same month last year. Still, diesel costs to run the turbines from April through last month have been reduced to about a third of the R17.1-billion spent during the same period in 2023, Eskom said.

The outlook of no power cuts, known as loadshedding, through the end of March, “remains in force,” it said.