Key Factors Slowing Eskom’s Load Shedding: An Unexpected Reprieve

South Africa’s electric public utility, Eskom, has recently made an unanticipated announcement: there will be no daytime load shedding until further notice. The progression from the perilous Stage 6 load shedding to Stage 3 or potentially lower, particularly during the winter season, has offered an unexpected sigh of relief.

The Unexpected Downshift

Only a few weeks back, South Africa was teetering on the edge of Stage 8 load shedding or worse. Thankfully, that has not come to pass. Despite the ongoing debate, Eskom’s coal generation fleet tends to perform better during winter than summer.

This past week witnessed a drop in load shedding from a peak of Stage 6 to a peak of Stage 3, marking a significant improvement.

What’s Behind The Change?

The adjustment of Eskom’s load shedding schedule to overnight until the morning peak is largely due to the significant difference between daytime power usage demand and peak demand. This discrepancy is especially sharp in winter, while the curve is considerably flatter in summer.

Here’s what has contributed to this unexpected light at the end of the tunnel:

1. Wind Power Surges: With cold fronts sweeping into the Western and Eastern Cape, wind generation has ramped up significantly. From Friday evening, wind generation consistently provided 2GW (or 2000MW) of power. This led to the welcome reprieve from load shedding over the past weekend.

2. The Koeberg Offset: While one Koeberg unit remains offline until September, the 2000MW of wind power in coastal regions equates to approximately 2200MW to 2400MW of power. This effectively offsets the impact of having 900MW offline.

3. Planned Maintenance: Eskom reports that only 2407MW is currently offline for planned maintenance. With constraints on Eskom’s maintenance budget, this might be a realistic amount of maintenance achievable in the winter months. However, it’s noteworthy that plants scheduled for shutdown are receiving minimal attention.

4. Utilization of Open Cycle Gas Turbines (OCGTs): OCGTs have been in significant use, with estimated expenditures reaching R3 billion a month, according to Eskom data.

5. Reduced Breakdowns: The final boost for Eskom has come from an unexpected quarter—breakdowns have been fewer than expected, with 16056MW reported as of Tuesday afternoon.

June’s Eskom data points to a significantly improved generation performance. The Energy Availability Factor (EAF), which measures how much generation capacity is online, is above 60%—the first time since August of the previous year. This highlights a potential turning point in South Africa’s load shedding saga, even if temporary.