A report by German consortium VGBE, compiled for National Treasury, has highlighted a concerning situation regarding Eskom’s coal-fired power stations. The report warns that without immediate repairs and upgrades to water treatment plants at key power stations, South Africa could face severe stages of load-shedding.

By Staff Reporter

If Eskom does not immediately address the issues with its water treatment plants at key power stations, South Africans could potentially face severe stages of load-shedding.

This is the sombre assessment provided by the German consulting firm VGBE Energy, which the National Treasury hired to assess the efficiency of Eskom’s coal-powered plants and suggest ways to enhance their performance.

The report indicated a high likelihood of experiencing a decrease in power generation capacity due to possible malfunctions in critical plant components caused by maintenance or operational issues.

VGBE’s team of engineering experts with significant experience in managing coal-fired power plants dedicated four and a half months to analysing the operations of South Africa’s struggling power utility. They meticulously assessed Eskom’s coal plants to identify necessary improvements for enhancing the performance of each station. The experts were particularly concerned about the deteriorating condition of several water treatment facilities at Eskom’s major power stations.

For instance, the water treatment facility at Matimba, which supports six units at Matimba and Medupi, urgently needs maintenance and upgrades to prevent a major breakdown.

Similarly, the ash filter and handling plants at Matimba and Kusile are also at risk due to insufficient maintenance and operational procedures, potentially resulting in additional power shortages.

The water treatment plant at Kendal is deteriorating and requires immediate maintenance and renovation; a breakdown of this plant could lead to the loss of six units producing 3,840 MW. To tackle this problem, the report suggests that an immediate temporary unit is necessary to facilitate the required refurbishment efforts.

The engineers also expressed concerns regarding coal quality, noting that it poses a challenge for numerous power facilities.

“Coal quality is an issue for many power plants. Impurities (mainly rocks) cause damage to the mills. Since the quality of the delivered coal cannot be influenced, efficient coal and sorting management should be carried out in the power plant as far as possible. On the other hand, there is a lack of space at some locations.

“Often, the results of the coal analysis are reported to the boiler operator after the coal is burnt. In this case, the boiler operator cannot respond to the coal change in advance. The coal quality must be checked when the coal arrives in the stockpile and, if necessary, the unusable coal must be rejected. The problem can be solved by intermediate storage and fuel management in the stockpile.”

Mitigating the risk of capacity losses and constraints

●The raw water treatment plant of the Medupi and Matimba power plants – both sites share this plant – urgently requires maintenance and upgrading. A second independent water treatment plant additionally would be an even better solution. If the existing plant fails, 12 units – 9 800 MW – would go off the grid.

●Moreover, the current water supply in the Lephalale region is not sufficient to install the wet flue gas desulphurisation plant at the Medupi site. Immediate actions should be taken to mitigate the risk and to develop alternative supply options.

●The water treatment plant at Kendal is in very poor condition and needs urgent maintenance and refurbishment. If the existing plant fails, 6 units – 3 840 MW – would be off the grid. A temporary unit is urgently required to enable this refurbishment work.

●Immediate actions are required to address the capacity limitations of the Kusile power plant which are due to the incomplete coal handling system and the ash discharge situation. These restrictions mean that the site cannot be operated with more than three units at the same time – hence only 2 400 MW instead of 4 800 MW would be available after the returning four units to operation. The four units refer to Unit 5 coming back within the next months and Units 1 to 3 after the completion of the temporary chimney construction.

●In several plants, e.g. Kendal, Kusile, Lethabo, Matla, Majuba, Matimba, Medupi and Tutuka, the current environmental permits to operate the plant are close to the limits of allowance or capacity in respect of: a) environmental compliance of flue gas emissions and b) to dispose of ash.

“It is strongly advised to clarify the permit situation for the short and long term to allow the operation of the plants in line with the legislation of South Africa.”