ZIMBABWE’S largest coal-fired power station remained subdued during the first quarter of this year, missing its quarterly generation output target by 55.78%, the Zimbabwe Power Company (ZPC) has said.
DUMISANI NYONI
In its quarterly update, ZPC said Hwange Power Station, situated in the western part of the country, operated with an average of two units during the quarter against a target of five units and sent out 411.42 gigawatt hours (GWh) of energy missing its quarterly target by 55.78%.
“Unit 3 continued to be unavailable throughout the period under review as it was on an extended major overhaul. Reliability of units 1, 4 and 5 was also affected owing to overdue planned outages and the fire incident which occurred on February 10, 2021 and caused extensive damage to units 1 and 2,” the report reads in part.
“The situation was worsened by the unavailability of Unit 6 towards the end of January due to leaking hydrogen coolers.”
Hwange Power Station has a production capacity of 920 megawatts (MW). But due to ageing equipment and constant breakdowns, the plant is producing only an average of 300MW.
Zimbabwe has been battling erratic power supply, which has seen load-shedding lasting up to 18 hours a day. The country’s power supply challenges have seen it resort to importing electricity from regional producers to cover the supply gap.
But regional utilities Hidroeléctrica de Cahora Bassa of Mozambique and Eskom of South Africa have indicated that they will not be able to export power outside firm contracts during winter as they also face huge demand.
This will worsen the electricity deficit in the country, currently sitting at 200MW.
Zimbabwe imports an average of 400MW from South Africa and Mozambique to narrow the electricity deficit.
The reports also showed that generation at Kariba Power Station had to be ramped up to compensate for the low generation levels at the thermal plants. the Zambezi River Authority allocated 30 billion cubic metres of water to Zesco’s Kariba north power station and Zesa’s Kariba South power plant for generation in 2021.
This translates to Kariba South Power Station having an annual water allocation of 15 billion cubic metres, which corresponds to an annual average capacity of 381MW.
The Kariba lake level rose from 478.38m at the beginning of the quarter to 481.84m at the end of March 2021, representing a 3.46m increase in lake level over the quarter.
The lake level at the end of the same quarter last year was 477.83m thus a 4.01m favourable difference. This implies an improved water situation in 2021 hence an anticipated water allocation increase.
As at the end of the first quarter, the station had utilised 5.43 billion cubic metres of water and generated at an average of 594MW, thus the station remains with 9.57 billion cubic metres for generation for the remainder of the year.
The small thermals sent out a combined 50.69GWh of energy, thereby missing the quarterly target which was set at 76.98GWh by 34.15%, the report notes.
“This was a great improvement from Q1 (first quarter) 2020 where the stations sent out a total of 11.67GWh. Generation was constrained mainly due to coal stockouts at Munyati and low boiler plant availability at Bulawayo Power Station,” it said.
Due to depressed output at Hwange, total power output for the quarter under review stood at 1745.70GWh against a target of 1813.02GWh, representing a negative variance of 3.71%.
The output was, however, 34.92% above the output for the same period in 2020.
ZPC said the Hwange Power Station’s unit 7 and 8 expansion project, which is expected to add 600MW to the national grid, registered progress of 58.29% at the beginning of the quarter and closed at 62.54% against an envisaged 85.9%.
“The project was affected by IPC outstanding payments as well as effects of Covid-19. Significant milestones in the quarter included arrival and hoisting of Unit 7 and 8 generator transformers, tower erection as well as steam turbine installation,” it said.
