Eskom’s weakest link: boiler tube leaks

Minister of Electricity Kgosientsho Ramokgopa briefing the media on progress made regarding the security issues related to the implementation of the energy action plan. Picture: Jairus Mmutle/GCIS

Minister of Electricity Kgosientsho Ramokgopa briefing the media on progress made regarding the security issues related to the implementation of the energy action plan. Picture: Jairus Mmutle/GCIS

Published Jul 18, 2023

Share

Electricity Minister Kgosientsho Ramokgopa has warned that boiler tube leaks across all Eskom’s coal-fired power stations continue to be the weakest link in the country’s electricity generation capacity.

This comes after Eskom ramped up load shedding to Stage 6 last week as demand surged on the back of inclement weather which saw temperatures plummeting to sub-zero levels.

Ramokgopa said yesterday that although Eskom had been making significant progress to stabilise the grid in the past three weeks, power stations were particularly vulnerable to boiler tube leaks, which caused unplanned outages for generation units.

“That’s the persistent failure that we are experiencing across all the power stations. It’s an area of technical shortfall that requires all of our attention. It has to do sometimes with the quality of coal,” Ramokgopa said.

“In our conversation with Eskom’s technical team, we said that we must just focus on this and in my other conversations with leading universities in the country… we tried to see if we can get people who studied this so that we are able to help the situation.

“This is our albatross and the majority of the units that had failed and gone out are as a result of boiler tube leaks.”

Ramokgopa said the electricity generation trendline had been positive over the past 21 days on multiple indicators, but there was a reversal on almost all of those indicators that was experienced last week.

The minister said this experience reconfirmed that the grid remained vulnerable and susceptible to plummeting.

He apologised profusely for Eskom having taken the country through intensive load shedding at a time when the weather was the coldest, saying load shedding was unacceptable.

“Going to higher stages of load shedding, especially Stage 6, should not become the norm. If anything, that should constitute an extraordinary occurrence,” Ramokgopa said.

“The intensity of load shedding that goes beyond Stage 4 is something that should be unacceptable and it’s something that, to the degree that we can, we will do everything to avoid.”

Eskom announced yesterday that load shedding would be reduced to Stages 1 and 3 today following the return to service of six generating units over the weekend.

The utility said breakdowns had reduced to 15 747MW of generating capacity while the generating capacity out of service for planned maintenance was 1 946MW.

“Since Friday, a generating unit each at Kriel, Lethabo, Majuba, Matla and two generating units at Arnot power stations were returned to service,” said Eskom interim spokesperson Daphne Mokwena.

“The delay in returning to service a generating unit each at Kendal, Matla and two generating units at Tutuka power stations is contributing to the current capacity constraints.”

Demand for electricity is expected to increase towards the weekend as the South African Weather Services has issued another warning of a cold snap, with wet weather predicted for Gauteng from Thursday.

Eskom head of generation Bheki Nxumalo said the surge in demand of 3 000MW last week due to cold weather had coincided with boiler tube leaks and resulted in exhaustive usage of pump storage and open-cycle gas turbines to keep the lights on.

“That day they ran a bit longer which then resulted in them not getting enough time to replenish, coupled with a number of tube leaks that we have at multiple stations. That is what caused us to increase the stages on Wednesday just to make sure that the system operator still maintains good reserves,” Nxumalo said.

BUSINESS REPORT