Hydropower shortages push Zambia and Zimbabwe back toward coal

Drought exposes dependence on hydropower

Climate-driven droughts are disrupting electricity generation in Zambia and Zimbabwe, two countries that have built large parts of their power systems around hydropower. More than 80% of Zambia’s electricity supply has come from hydropower, while the technology has accounted for about half of neighboring Zimbabwe’s supply.

That concentration leaves both systems exposed when drought reduces the water available for generation. The resulting pressure is not confined to electricity producers. Unreliable supply can affect mines, processors, manufacturers and other power-intensive businesses, while also complicating decisions on production schedules and investment.

The shortages are renewing interest in coal as Zambia and Zimbabwe seek electricity sources that are less directly dependent on rainfall. Coal can provide dispatchable generation when hydropower output falls, but a return to the fuel would deepen the tension between immediate energy-security needs and efforts to reduce reliance on high-emission power.

Coal returns to the energy debate

The renewed focus on coal reflects the scale of the hydropower risk. In Zambia, where more than four-fifths of supply has depended on water, a prolonged generation shortfall can quickly become a national industrial constraint. Zimbabwe has a more diversified starting point, but hydropower’s roughly one-half share still makes low-water periods significant for the wider economy.

For producers and electricity buyers, the central issue is dependable capacity. Hydropower remains valuable, but drought has demonstrated that installed generating assets cannot guarantee output when water availability deteriorates. Coal therefore returns to the discussion not necessarily as a replacement for hydropower, but as a source capable of supporting the system during periods of weak hydro generation.

The commercial effects extend through supply chains. Electricity interruptions can reduce operating time, raise unit costs and make deliveries less predictable for processors and manufacturers. Mining companies and other large consumers must also account for power availability when assessing output targets, maintenance and future capacity.

Regional consequences

The impact may spread beyond national borders because power systems in Southern Africa are interconnected. When Zambia or Zimbabwe has less surplus electricity available, neighboring markets have fewer options for balancing their own shortages. Greater competition for regional supply can also increase the importance of domestic generation choices.

Coal may offer operational support, but it does not remove the underlying exposure to climate shocks. Zambia and Zimbabwe still face the task of building electricity systems able to function through changing hydrological conditions. For industrial users, traders and investors, the key question is whether new capacity can provide reliable power without creating another concentrated dependency.

The renewed coal debate is therefore a measure of how urgently both countries need firm electricity supply. Hydropower provided Zambia and Zimbabwe with a large domestic generation base, but drought has revealed its limits. Decisions made in response will shape industrial competitiveness, regional electricity availability and the balance between energy security and emissions.