A Winter of Worry: Eskom Downplays Stage 6, Yet Experts Predict Darker Days Ahead

Eskom’s Load Shedding Forecast

The upcoming winter’s load shedding forecast looks rather grim, but Eskom is confident that it will not reach Stage 6. Despite their optimism, independent analyst Clyde Mallinson has a more pessimistic outlook.

Eskom’s Expectations

Eskom’s projections are based on:

• Lower maintenance during winter
• Slightly improved plant performance in colder months

In hot weather, Eskom’s coal-fired power stations experience “load losses,” resulting in reduced generation performance. However, winter brings some relief as Eskom typically scales back planned maintenance by at least 3,000MW.

Challenges Ahead

Load shedding will still be unavoidable due to:

• Four units of Kusile (3,200MW) being down until at least November
• One unit of Medupi (800MW) being down
• One unit of Koeberg (920MW) being down through winter

Eskom’s chief operating officer, Jan Oberholzer, admits that the outlook isn’t positive, but they’ll try their best not to exceed Stage 4 and never reach Stage 6.

Electricity Minister’s Message

Kgosientsho Ramokgopa, the Electricity Minister, echoed a similar sentiment during a visit to Koeberg. He assured the South African public that higher stages of load shedding beyond Stage 6 are unlikely.

Mallinson’s Forecast

Mallinson’s load shedding forecast varies between Stage 2 and Stage 3 over winter when running diesel open cycle gas turbines (OCGTs) unconstrained. However, when considering financial and logistics constraints on diesel burn, the load shedding stages could increase by two levels. Mallinson’s predictions are based on two key assumptions:

1. The 2023 load profile will be similar to 2022
2. Load shedding is strongly correlated to the demand profile and coal plant load factor or capacity

Mallinson presents two possible scenarios:

Scenario 1: Unconstrained Diesel Use

• Diesel peaker plants are used as needed, sparing South Africa from two stages of load shedding
• Running OCGTs at high load factors isn’t financially or logistically feasible due to insufficient storage capacity and diesel replenishment rate
• Assuming a coal plant average load factor of 49% and unconstrained diesel use, expect average load shedding of Stage 2 throughout winter

Scenario 2: Diesel Peaking Plants Run Only at Peak Times

• Diesel peaking plants are used during peak times, considering financial and logistical constraints
• Assuming a coal load factor of 49%, average load shedding over winter will increase to Stage 3 and Stage 4
• If the coal fleet load factor remains at an average of 49%, South Africa may experience its first official instance of exceeding Stage 6, likely in June

Eskom’s Diesel Spending

As the financial year draws to a close, Eskom will have spent R22 billion on diesel during 2022/23. However, the National Energy Regulator of SA (Nersa) only permitted R6 billion for diesel spending, leaving R16 billion unaccounted for.