Eskom's diesel bill falls by four fifths, and the scarcity window narrows with it.

For a generator or PPA holder selling into the evening peak, the hours in which the South African electricity market pays for scarcity have thinned. Eskom ran its diesel turbines at a load factor of 1.06% for the financial year to 17 September 2026, against 7.25% a year earlier, and spent R1.13 billion on diesel where it spent R5.93 billion, a fall of R4.80 billion or 80.95%.

The fleet behind that is steadier rather than transformed. Availability for the year to date reached 67.96%, up from 62.17% last year and the strongest year to date figure in six years, with unplanned outages at 19.23%, which Eskom puts at 6.92% below the same period a year ago. The week itself was flat: 72.74% availability against 72.96% in the matching week last year, with more plant deliberately out for maintenance, 13.01% against 11.16%.

Headroom is the number that prices. Eskom is holding 8 716MW in cold reserve because capacity exceeds demand, and forecast its evening peak at 22 081MW against 27 500MW available. Loadshedding has now been absent for 490 days running, counted from 16 May 2025, and the utility says its power system status and Summer Outlook are due in the coming weeks.

Read together, those figures move the argument for private generation off avoided outage cost and onto tariff and wheeling economics, which turn on regulatory process at NERSA rather than on how the coal fleet performed last week.

What remains of supply interruption is no longer a generation problem. Load reduction now touches 247 617 customers, 3.4% of Eskom's base, down from 1.69 million, with the remainder in Gauteng and KwaZulu-Natal, and Eskom attributes it to illegal connections and meter tampering in specific areas rather than to any shortage of power. The utility says it is on track to end the practice by March 2027.

The Summer Outlook is the document to read next, because it will put a number on how long this surplus is expected to hold.