eBusiness Weekly
Golden Sibanda
Zimbabwe is now generating significantly less power at Kariba South than the plant’s rated capacity. This is after it exceeded its allocated ration by 57 percent in the first quarter of this year, as it battled supply challenges at Hwange Power Station.
State power utility Zesa is now only left with allocated water enough to generate a maximum of 358 megawatts for the rest of this year, as lake water levels drop. Kariba South can generate up to 1 050 megawatts if the water level permits.
To avoid depleting the lake, Zambezi River Authority, which administers the affairs of the Zambezi River, on which Lake Kariba is situated, has allocated Zimbabwe 8 billion cubic metres of water for the rest of this year, enough for 358MW.
This is despite the fact that Kariba South, which underwent an expansion programme about five years ago, now has rated capacity to churn out 1 050MW, but fast receding lake water levels have forced reduced use of water for power generation.
Zesa over depended on Kariba for power on the back of challenges experienced at the country’s second largest power station, Hwange, which saw it using more than its allocated amount of water by 57 percent.
However, Zambia also exceeded its allocated water limit in the first quarter by 27 percent. The over usage of water by power utilities of the two countries, which depend heavily on Kariba, has seen the lake levels falling fast.
Zimbabwe Power Company (ZPC), the generation arm of ZESA, acting managing director, Engineer Robson Chikuri, told the new Energy and Power Development Minister Fortune Chasi that they were left with only 8 billion cubic metres.
He said it was critical that ZPC adheres to the allocated amount of water to avoid reducing the lake water levels below its minimum operating level of 475,5 metres, at which point the inlet valves that feed generators would be exposed.
At full capacity, the Lake Kariba can rise to a maximum holding water level of 489 metres through its live water, the height between the minimum and maximum operating level (485 metres), for power generation, is a span of 10 metres.
The Kariba Dam received 60 percent less water inflows during the last rainy season, due to the drought that was experienced in areas around the reservoir’s catchment area, which stretches 2 700 kilometres north western Zambia.
Secretary for Energy and Power Development Engineer Gloria Magombo said ZPC had used more than its allocated amount of water due to over reliance on Kariba South, on the back of generation challenges at Hwange Power Station.
The plant is Zimbabwe’s second biggest power plant after Kariba.
The thermal power plant is supposed to carry Zimbabwe’s base load, that is provide power during peak and off peak period, while Kariba would be a peaking station, only kicking during peak demand periods in the morning and evening.
Previously, this gap was bridged using electricity imports from the region.
This, she said was the reason Zambia was being allowed to generate more power from the dam’s remaining water available for purposes of power generation.
