The State Of Eskom’s Transmission Grid In The Western Cape

Mr Lester Geldenhuis, Chief Engineer at Eskom in the Western Cape, was Premier Alan Winde’s guest at his 22nd Energy Digicon.

Mr Geldenhuis shared his insights into the power utility’s transmission grid development efforts, generation forecasting as well as the increasingly important role independent power producers (IPPs) are playing in power generation in the province.

During the Digicon, we asked, what does the Western Cape’s grid “look like”?

• The province’s transmission network comprises 18 substations and 31 lines totaling 3350 km; and
• More than 4500 MWs of power is generated in the Western Cape, with 4000 MWs at peak periods, and IPPs contributing just over 1000 MWs to the grid.

Examining the state of the grid, Mr Geldenhuis explained, “What we normally do is calculate the number of circuits on the western grid that are available. At this stage we are not doing badly in terms of unavailability which in total is under 1% (for the current financial year).”

Looking to the future, Mr Geldenhuis said that Eskom expects to grow the province’s load forecast between 2023 and 2032 by around 5.3 GWs. Generation is expected to be increased by 6800 MWs, with wind making up the much of this target.

The three regions, known as renewable energy development zones of the province, which provide the most opportunities for renewable energy technology and projects are:

• Overberg;
  Komsberg; and
  Beaufort West

With the Western Cape’s population growing at a rapid rate, energy demand will constantly increase. This puts added pressure on Eskom. Mr Geldenhuis looked at developments in the pipeline aimed at keeping up with demand, such as a substation to be set up near Mitchells Plain, another transformer earmarked for Stikland, along with extending the substation in the Philippi area. Beyond Cape Town, Eskom is working towards establishing a second transformer in the Ceres region and a substation in George, among other long-term projects. “Normally what we look at is population growth and we base our transmission development plan on that,” he said.

Apart from growing demand for electricity, the utility is also facing numerous challenges posed by for example land invasions, as it tries to expand its operations.

When asked how the Western Cape Government (WCG) can assist Eskom with its expansion programme, Mr Geldenhuis said, “Apart from the funding issue, I think where we can work together is in terms of the execution. We see that going into places like Philippi, going into places like Mitchells Plain to create assets will be challenging. We need to work together (Eskom, provincial and city government) to see where we need to build our substations and power lines to safely execute that infrastructure.”

On the issue of the vulnerability of the Western Cape’s grid due to much of the coal-fired power being concentrated in the north of the country, Premier Winde remarked, “As a provincial government we have set ourselves the target of reducing offtake from Eskom by 5 700 MWs over the next several years, which aligns with the company’s future targets to move power around. At the same time, we are also looking at local government networks. We must ensure these two networks are aligned. We must all work closer together.”

Mr Geldenhuis agreed, pointing out, “In the past couple of years we have seen power flowing up to the northern parts of the country.” This as more energy generation is spread around the country. “It is important that we look at how we are going to change our network,” he concluded.