Hwange power plant output falls to 10%

THE Zimbabwe Power Company (ZPC) is at various stages of repairing four units at Hwange Power Station after a series of breakdowns led to a sharp drop in power supply, after output at the country's second-biggest plant operating fell to just 10 percent of available capacity.

A general supply summary report produced by ZPC, a unit of Zesa Holdings responsible for generating electricity, shows that between February 15 and 23 this year, four units at the Hwange thermal power plant were switched off, leaving the plant operating with one.

Zesa spokesperson Dr George Manyaya promised to provide comment after "getting a status update from the technical team" yesterday, but he had not done so by the time of publishing.

Hwange, designed to produce 920 megawatts, has been constantly hit by breakdowns due to old equipment, leading to severe and regular unscheduled power cuts, also known as load shedding. Unit 4 was switched off on 15 February after developing a boiler tube leak. Unit 1 was taken off on February 24 after a high-pressure fan got damaged.

Unit 3 was stopped on February 24 after developing a tube leak while Unit 6 was switched off on February 23 after developing a similar problem. The damaged units are at various stages of being repaired. Unit 5 tripped in October 2021 due to excessive turbine vibrations.

Energy and Power Development Minister Zhemu Soda said last year that the old units would be de-commissioned and rehabilitated to restore the plant's designed capacity.

The Government has already secured US$310 million from the Export-Import Bank of India to rehabilitate the six old units and rebuild the plant under a phased programme, which would commence once new generators, 7 and 8, are commissioned.

"We are likely to have two units decommissioned at a time (to pave way for rehabilitation) until all the units have been repaired," said Minister Soda. "We are looking at restoring the capacity of all the units to 920 MW upon completion," Minister Soda said.

Some energy analysts have applauded the move by the Government, saying the only "viable option" was to decommission the existing units as it has become clear that the plant can no longer be managed. "We can do life extension of the plant including complete overhauls," said one analyst who declined to be identified.

ZPC is in the process of commissioning Hwange unit 7, which will churn out 300 MW. Unit eight will be switched on later this year and will produce the same amount of electricity.

Kariba hydroelectric plant is currently producing between 270–475MW with four units (350MW on average). Unit 4 was taken out on July 20 2022 due to a damaged turbine runner.

Generator 1 was switched off on February 2 2023 for turbine runner inspection. The inspections have been completed and the unit has been placed on annual maintenance.

Unit 8 tripped on 20 December 2022 due to GTx 8 fault and is being replaced.

Unit 6 was taken out on December 16 2022 for an annual overhaul and machine cooling water pipework replacement. Kariba dam level has slightly improved to 13,75 percent.

In terms of small power stations, Munyati and Bulawayo are currently switched off for boiler maintenance. From Independent Power Producers, ZXIN is churning out 39MW, Green Fuel; 0MW, Hippo Valley Estates; 0MW, Tsanga; 7MW and Pungwe Hydro; 21MW. Zimbabwe is importing 50MW from Hidroeléctrica de Cahora Bassa; 180MW from Eskom, between 130-200MW from Electricidade de Moçambique and 1 00MW Zambia's state-owned power utility Zesco. The country is exporting up to 80MW to Namibia.