Eskom’s reduced use of costly gas turbines signals power stability

South Africa is edging closer to 100 days without loadshedding (93 days at the time of writing). This is the longest loadshedding-free stretch since 2020. Eskom is also relying much less on diesel-powered gas turbines (OCGTs and GTs), an indicator of increased stability and output in the power-generation network.

In April, May and June this year, Eskom generated 571 gigawatt hours (GWh) of power using gas turbines. In the same period in 2023, it generated 1,583GWh using diesel power.

The use of OCGTs is intended as a strategic measure to supplement drops in power generation rather than as a long-term solution. Running OCGTs is also expensive. Eskom reported spending R3.1-billion in April 2023 to produce 470GWh of power.

The cost of generating power using OCGTs is about five times more expensive than coal generation. Some estimates suggest OCGTs cost about R3/kWh, while coal power costs about R0.42/kWh. Other estimates put these higher but the difference remains roughly the same.