Eskom responds to water crisis with Koeberg desalination plant

Johannesburg - A new desalination plant at the Koeberg nuclear power station will attempt to alleviate some of Cape Town’s water woes.

State power utility Eskom announced on Wednesday that it has launched a mobile groundwater desalination plant, which will take care of the station’s own potable water needs.

This, Eskom said, would ease the pressure on the City of Cape Town’s water supply.

The 1 860 MW Koeberg nuclear plant, Africa’s only nuclear power station, provides 50% of the Western Cape’s and approximately 5.6% of South Africa’s energy needs. Although it uses mostly seawater to cool down its reactors, the plant does need some fresh water, mostly for day to day operations.

But Koeberg only uses about 1 370 kilolitres of potable water per day for its operations, compared to the seven million kilolitres of seawater per day. Koeberg saves 22 billion litres of fresh water per annum as its condensers are cooled by means of sea water, which is returned to the sea after use.

Despite its reliance on seawater, Koeberg can only operate about two weeks without off-site potable water. Velaphi Ntuli, Koeberg Power Station Manager, said the desalination solution was therefore quite important to ensure continuity of supply of potable water.

“This equates to the City of Cape Town supplying 10.5 kl of water to approximately 11 000 houses for a month. Our water tanks are kept full to cater for emergencies,” he said.

At a local community meeting last year to discuss the plant, Eskom representatives said that Koeberg in earlier years had a desalination plant, but it was taken out of service many years ago due to operational reasons. It was not economically feasible to refurbish that plant and thus a new plant was commissioned.

“When the City of Cape Town called on the people of the Western Cape to address the water issue, we had to respond with a sustainable solution as a responsible corporate citizen,” said Ntuli.

He said the desalination plant was part of Koeberg’s three-pronged water management strategy to address the current water shortages in the Western Cape, while ensuring that the plant is able to provide safe and sustainable electricity.

“This strategy includes reducing the power station’s daily water usage, keeping adequate on-site water storage and looking at alternative water supplies for both groundwater and sea-water,” he said.

Ntuli said Koeberg had saved approximately 115 000 kl since June 2017, compared to previous averages.  

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