The supply of electricity from Cahora Bassa Hydroelectric (HCB) in Mozambique has been identified as an essential pillar of South Africa’s energy security, according to Eskom’s latest report covering the period 2026–2030.
According to Engineering News, the “Medium-Term System Adequacy Outlook”, released on October 30, assesses South Africa’s ability to meet projected electricity demand and highlights growing risks if synchronization fails between the closure of coal-fired power plants, the commissioning of new gas-fired stations, and the completion of transmission network upgrades.
The agreement with HCB, which guarantees the supply of 1.15 GW of power until at least March 2030, is considered crucial to avoid load shedding, as Eskom prepares to retire 8.4 GW of coal capacity between 2029 and 2030. The simultaneous shutdown of these plants would create a 9.5 GW shortfall in firm capacity.
The report outlines three demand growth scenarios based on economic performance. In the moderate scenario, demand rises from 243 TWh in 2024 to 264 TWh in 2030, growing at an annual rate of 1.4%, and depends directly on the continued supply from Mozambique.
On the supply side, South Africa’s installed capacity remains dominated by coal, complemented by solar, wind, diesel, nuclear, and battery storage. Although renewable energy expansion has been significant, it faces transmission constraints — particularly in the Eastern Cape, where the Poseidon substation experiences curtailments exceeding 70% of injected solar power. The commissioning of 6 GW of combined-cycle gas power plants by 2030 is seen as critical; any delay could raise unserved energy to over 4 TWh, equivalent to 80 days of Stage 4 load shedding.
Eskom also stresses the need to reinforce the transmission network, citing projects such as the new 400 kV substations in Kyalami and Bighorn, which are only expected to become operational after 2030. Other challenges include system frequency instability and growing surplus generation, particularly from solar sources.
The HCB supply therefore stands out as one of the few stable and predictable external power sources. Its continuity is regarded as strategically vital, not only to meet South African electricity demand but also to cushion the impacts of the energy transition and infrastructural vulnerabilities in the neighboring country.
Source: Diário Económico
