Johnson Progress

The Zimbabwe Electricity Supply Authority (ZESA) says power has been restored to most parts of the country following a nationwide blackout on Monday evening, after a major fault knocked out a key transmission line linking the national grid to regional power sources.

According to a technical update issued by the utility, the fault struck the Warren–Alaska 330kV transmission line at 6:24 pm on Monday.

ZESA explained that the failure caused Zimbabwe to lose its interconnections with neighbouring regional power utilities, triggering a cascade of technical problems across the network.

The utility said the disruption led to voltage instability and under-frequency conditions on the grid, which in turn forced the automatic shutdown of local power generation units as a protective measure.

The scale of the outage meant that homes, businesses and essential services across the country were left without electricity for several hours, with no clear timeline initially given for restoration.

ZESA said its engineers moved quickly once the fault was identified, with restoration efforts beginning at 7:01 pm just over half an hour after the blackout began.

Supplies were brought back gradually, the utility said, through a combination of imports and local generation, drawing power from Eskom in South Africa, the Kariba Power Station, the Hydro Cabora Bassa scheme, and Hwange Units 1, 2 and 3.

By 10:00 pm, ZESA reported that electricity had been successfully restored to most bulk supply points nationwide, marking a return to relative normalcy for the majority of consumers less than four hours after the initial fault.

However, the utility cautioned that restoration work was not yet fully complete.

ZESA said engineers were continuing efforts to synchronise the remaining generating units at Hwange Power Station, which had been knocked offline during the disturbance.

Teams were also said to be carrying out repairs at the Warren Substation, a facility that supplies electricity to parts of Harare and which bore the brunt of the technical fault.

In its statement, ZESA struck an apologetic tone over the disruption.

“We sincerely apologise for the inconvenience caused to our customers,” the utility said, adding that technical teams remained on site to complete the outstanding restoration work.

The blackout is the latest in a series of technical challenges to hit Zimbabwe’s power grid, which has repeatedly faced strain from ageing infrastructure and heavy reliance on interconnections with regional suppliers to plug gaps in domestic generation capacity.

Monday’s fault underscored how a single point of failure in this case, one transmission line can ripple across the entire national grid, disconnecting it from neighbouring power pools and forcing an emergency shutdown of local stations.

ZESA has not yet given a full account of what caused the fault on the Warren–Alaska line in the first place, nor a timeline for when repairs at Warren Substation and the synchronisation of the remaining Hwange units will be complete.

Customers in affected areas have been urged to remain patient as technical teams continue restoration work.

Further updates are expected from ZESA as engineers finalise repairs and confirm full restoration across the network.