ZESA Reveals Cause of Nationwide Power Blackout That Left Zimbabwe in Darkness

By Staff Reporter
Zimbabwe's power utility, ZESA Holdings, has revealed the cause of the nationwide electricity blackout that plunged the country into darkness on the evening of Monday, 6 July 2026, attributing the outage to a major fault on its high-voltage transmission network.

The blackout, which began at 6:24 pm, disrupted electricity supplies across Zimbabwe after a critical fault occurred on the Warren–Alaska 330kV transmission line. According to ZESA, the incident severed the country's interconnections with neighbouring regional power utilities before triggering instability within the domestic electricity generation system.

In a technical update issued on Tuesday, 7 July, the utility explained that the transmission fault led to a loss of voltage stability and a drop in system frequency, forcing local power generation units offline.

"At 1824 hours, a major electrical fault occurred on the Warren-Alaska 330kV line, leading to loss of interconnections with neighbouring regional utilities. Subsequently, local generation was lost due to voltage instability and under frequency," ZESA said.

ZESA said restoration efforts commenced at 7:01 pm, less than an hour after the nationwide outage.

To stabilise the national grid, engineers secured emergency electricity imports from Eskom in South Africa, Kariba Power Station, and Hydro Cabora Bassa in Mozambique. Generation from Hwange Power Station Units 1, 2, and 3 was also brought online as part of the recovery process.

By 10:00 pm, the utility reported that electricity had been restored to most of the country's bulk supply points.

> "We are pleased to advise that by 2200 hours, power had been successfully restored to most of our bulk supply points across the country," the utility said.

Work Continues at Hwange and Warren Substation

Despite significant progress in restoring electricity, ZESA said technical teams remain on the ground working to fully stabilise the national grid.

The utility is continuing efforts to synchronise the remaining generating units at **Hwange Power Station**, while engineers are also carrying out repairs at the **Warren Substation**, a key facility that supplies electricity to parts of Harare.

ZESA apologised to customers for the disruption, saying its teams are working around the clock to complete the remaining restoration work and ensure the network returns to normal operations.