The Sunday Mail
Improved water levels in Kariba Dam and imports from the region are expected to guarantee uninterrupted power supplies until year-end.
The latest update from the Zambezi River Authority (ZRA) shows that water levels in the dam rose from 21 percent of live water to 41 percent by mid-July.
Live or usable water storage refers to all the water above Kariba Dam’s minimum operating level of 475,5 metres.
The giant reservoir’s water level can rise to 489 metres when filled to capacity.
Zimbabwe’s power situation deteriorated to crippling levels last year after the country and the entire region was affected by the worst drought in 40 years. Water for power generation was subsequently restricted.
The lake level receded for the most part of the first quarter due to the delayed onset of the rainy season, which only began in January this year, instead of October 2019 as earlier forecast by experts.
“Following the commencement of the rains, the lake water levels began to increase starting about mid-January 2020, rising from 476,7 metres, which was barely 1,21 metres above the minimum operating level (MOL).
ZRA said the lake reached a peak of 481,3m on June 30, 2020, with a corresponding usable storage of 26,9 billion cubic metres (BCM) or 41,6 percent live storage.
“Thereafter, the lake level started receding. As of July 16, 2020, the lake level had receded to 481,2m, representing 40,9 percent live storage or 26,50 BCM of stored usable water.
“This left the lake level at 5,71 metres above the (MOL) of 475,5 metres,” ZRA said.
Following a review of the hydrological outlook at Kariba Dam undertaken at the end of the second quarter of 2020, the ZRA has since increased the water allocation for power generation operations at Kariba by 4 billion cubic meters (4BCM).
Confederation of Zimbabwe Industries vice president Mr Joseph Gunda said they had received assurances from state power utility, ZESA, that power cuts were unlikely until the end of this year.
Average local power generation has risen to 1 000 megawatts (MW) and is being complemented by regional imports of 450MW.
Kariba Hydroelectric Power Station — the country’s largest power plant with output potential of 1 080MW — has been able to shore up production due to significantly improved dam water levels.
However, demand, which has averaged 1 200MW since March 2020 — has been relatively low owing to suppressed demand due to Covid-19 restrictions.
It only rose to 1 450MW after the beginning of the winter season. With the summer season now imminent, demand is projected to slump significantly. Local power demand often peaks at 2 200MW, especially during winter, outstripping reliable internal generation capacity of about 1 600MW.
Hwange Power Station — the country’s second-largest plant — is often dogged by frequent breakdowns due to aged equipment.