Eskom’s high-tech push to modernise the grid

Eskom’s high-tech push to modernise the grid


A stabilising Eskom is starting to place a stronger focus on new technologies and the modernisation of the electricity grid.

Last month, at the release of the state-owned utility’s annual results, CEO Dan Marokane said the utility is focused on “deepening the adoption of digitalisation in the business”, through measures such as the use of data analytics and artificial intelligence.

At the same time, it is diversifying its technology mix, including developing a pipeline of clean energy, with at least 2GW of projects ready for execution to expand its energy mix by 2030 – and a longer-term pipeline of 5.9GW encompassing solar PV, wind, battery storage and gas-to-power projects.

It is also exploring emerging technologies such as small modular reactors and long-duration energy storage. More than R100-billion has been allocated to strengthen and expand the transmission and distribution networks over the next five years to help improve system reliability, unlock grid capacity and enable renewable energy integration.

According to Eskom’s 2025 integrated report, the transformation of South Africa’s electricity supply industry demands a modern, flexible and digitally enabled power system. In response, it is accelerating investment in infrastructure, digitalisation and smart technologies.

It will roll out around seven million smart meters and 250 microgrids over the next five years to support demand flexibility and reduce energy losses, it said.

A key goal in the coming years is connecting 97% of households to the national grid. The remaining 3%, who are largely located in remote and rural areas, will be served through non-grid-based solutions, including microgrids, where grid-based solutions are impractical. During the year, 83 031 households were connected to the grid. A microgrid is a localised electricity grid that can operate independently or connect to the main power grid to supply power to a specific area.

Microgrids

“We are targeting the installation of containerised microgrid units to address rural electrification challenges. These will be prioritised for hospitals, clinics, schools and essential services centres in vulnerable communities,” the report said.

“The microgrids will leverage renewable technologies, such as solar PV, to electrify previously unserved areas. A regulatory framework for microgrids is being developed in collaboration with [energy regulator] Nersa and other stakeholders to establish guidelines and standards for implementation of microgrid technology.”

Eskom’s Medupi power station, meanwhile, is undergoing a flue gas desulphurisation retrofit (FDG) – a key step in meeting environmental standards and fulfilling World Bank funding conditions. The upgrade will cut sulphur dioxide emissions once completed, it said.

Read: Eskom in dramatic swing into profit

While Kusile power station was commissioned with wet FGD technology installed, Medupi’s original business case included a commitment to retrofit FGD systems within six years of each unit’s commissioning. The project remains in the development phase.

The annual report said the investment and finance committee of Eskom’s board has approved a revised strategy, which confirms wet FGD as the preferred technology. The request for proposal for the project and the closing date has been extended to 2 February 2026 following requests from bidders.

EskomEskom said the final schedule will depend on the chosen contractor’s execution schedule, the technology solution selected and the power station outage plan.

Eskom said progress on the final three FGD units at Medupi hinges on a new water supply line from Thabazimbi, which is managed by the Trans-Caledon Tunnel Authority under the water & sanitation department.

The line is expected to be completed by January 2030. Water for the first three units of Medupi’s FGD retrofits will be available from the existing Mokolo Dam.

It said the original cost estimate of R38.4-billion has been revised to R41.7-billion due to “inflationary pressures” and “market dynamics”. However, this estimate will be further refined following the conclusion of the tender process.

Another cornerstone to modernising Eskom’s grid and integrating renewable energy is its battery energy storage system (Bess) programme. Phase 1 of the programme will deliver around 800MWh of storage capacity across four implementation packages. While construction activities have been delayed, they continue at the Skaapvlei, Graafwater and Paleisheuwel sites in the Western Cape.

Eskom said all the battery equipment has been delivered and commissioning is anticipated during the next financial year. Phase 2 of the project is on hold due to debt relief conditions from the government and a lack of funds from Eskom’s own reserves. However, the 600MWh Komati PV and Bess project in Mpumalanga has been separated from phase 2 and is proceeding under existing approvals.

National grid code

On research, testing and development, the unit in charge has advanced several high-priority initiatives. They include high-resistant fabric filter bags installed at Medupi and Kusile to deal with corrosion and erosion in fabric filter plants; piloting plasma and mini oil burner ignition systems to reduce fuel oil consumption during start-up and low-load operations; and concluding research on grid-forming inverters to enhanced grid stability in utility-scale renewable integration.

Lastly, it said recommendations based on the Finnish specification will be proposed to update the national grid code. A national grid code sets the technical and operational standards that everyone connected to the grid – power stations, renewable farms, transmission companies, big industrial users and even new entrants like battery storage operators – must follow.

Read: Medupi unit 4 rejoins grid, easing winter load shedding fears

Dynamic volt-amp reactive (D-VAR) technology is also being piloted to manage voltage fluctuations caused by variable solar and wind generation on medium-voltage networks.  – (c) 2025 NewsCentral Media

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