Maputo, May 4, 2026 (Lusa) – The reservoir of Mozambique's Cahora Bassa dam, one of Africa's largest, has recovered to 56% of its water storage capacity following historic lows, and management now acknowledges that production in 2026 could exceed previous forecasts.
In information sent to Lusa by Hidroelétrica de Cahora Bassa (HCB) regarding 2025 performance and future outlooks, the company said that prospects for 2026 "are encouraging, reflecting the recovery of water storage levels in the reservoir, currently at 56%." This storage level could enable a production increase beyond the planned 11,716.76 Gigawatt-hours (GWh), representing growth of more than 7.29% compared to 2025.
HCB said that it will remain focused on "prudent resource management, operational efficiency, and the adoption of technological solutions."
The company acknowledged that 2025 was marked by operational challenges due to a continuous reduction in water storage. At the end of the 2024/2025 rainy season, levels stood at 26.01%. "In response, the company implemented a restriction and recovery programme that improved storage levels to 27.23% by 31 December 2025, compared to 21.19% in the same period of 2024, signalling a recovery trajectory," it said.
The firm also noted a production of 10,921 GWh last year, representing a 30% year-on-year decrease.
HCB is a private limited company, 85% owned by the state firm Companhia Elétrica do Zambeze. Portugal’s Redes Energéticas Nacionais (REN) holds a 7.5% stake, while the company maintains 3.5% in treasury shares. Mozambican citizens, companies, and institutions hold the remaining 4%. The Cahora Bassa reservoir is Africa’s fourth largest, stretching 270 kilometres in length and 30 kilometres between banks. It covers 2,700 square kilometres with an average depth of 26 metres. Employing nearly 800 workers, it ranks among the largest electricity producers in Southern Africa, supplying several neighbouring countries. Mozambique's electricity production fell by 25% in 2025, driven by the water shortage at HCB following the "worst rainfall record" in 43 years.
The government's 2025 budget execution report shows that national electricity production reached 14,408,381 Megawatt-hours (MWh), or 14,408.3 GWh, representing 76.7% of the annual plan and a 25.4% decrease compared to 2024.
"The low production was largely due to the weak performance of hydroelectric plants, which recorded an execution rate of 72.3% and a 30.7% decrease compared to the same period in 2024," the document says.
The country is "the largest producer of hydroelectricity in Southern Africa," and "nearly all of its production comes from HCB," supplemented by other small dams managed by Electricidade de Moçambique, it said.
In 2025, hydroelectric plants generated 11,207,934 MWh (11,207.9 GWh), a 30.7% drop from 2024. It attributes this performance "largely to the effects of the El Niño phenomenon, which has affected the HCB plant since 2023."
"The scarcity of rainfall in the Zambezi basin [where HCB operates] reduced water availability in the country's main reservoirs (Corumana, Mavuzi, and Chicamba), resulting in the 2024/25 hydrological year having the lowest rainfall record of the last 43 years," the central bank report said.
The lack of affordable energy was central to a dispute that led the Mozal aluminium smelter, the country's largest employer, to suspend operations on 15 March, affecting more than 4,000 jobs.
PVJ/RYOL // ADB.
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