Eskom opens Africa’s biggest battery storage facility

Admire Moyo
By Admire Moyo
Johannesburg, 10 Nov 2023
Eskom's Hex BESS site at Worcester in the Western Cape.
Eskom's Hex BESS site at Worcester in the Western Cape.

Under-fire power utility Eskom has unveiled what it dubs the first of its kind and the largest battery energy storage system (BESS) project, not only in South Africa, but on the African continent.

Eskom officially opened the Hex BESS site at Worcester in the Western Cape yesterday.

The announcement comes as the power utility, which supplies the bulk of South Africa’s electricity, has over many years been struggling to keep the lights on in the country.

Poor maintenance at the ageing coal-powered power stations and corruption have been cited as the biggest reasons for the challenges facing the state-owned company.

Over the years, Eskom has implemented power cuts to avoid the total collapse of the fragile national electricity grid.

In a statement, Eskom says the Hex BESS is the first project to be completed under Eskom’s flagship BESS project announced in July 2022 to help alleviate the pressure on the national electricity grid.

It notes the BESS project serves as a direct response to meet one of the urgent needs to address South Africa’s long-running electricity crisis by adding more storage capacity to strengthen the grid, while diversifying the existing generation energy mix.

The facility uses large-scale utility batteries with a total capacity of 1 440MWh per day and a 60MW PV capacity.

According to Eskom, the Hex site is designed to store 100MWh of energy, enough to power a town such as Mossel Bay or Howick for about five hours.

It forms part of phase one of Eskom’s BESS project, which includes the installation of approximately 833MWh additional storage capacity at eight Eskom distribution substation sites in KwaZulu-Natal, Eastern Cape, Western Cape and Northern Cape. This phase also includes about 2MW of solar photovoltaic (PV) capacity.

“We are grateful to the various funders of the Eskom BESS project, and to our construction partner Hyosung Heavy Industries. This is proof of what we can achieve when we work as a team and in collaboration with industry and local communities,” says  Monde Bala, Eskom group executive for distribution.

The utility explains that the BESS technology offers a versatile solution for improving overall grid performance and is in line with South Africa’s commitment to the just energy transition to a more resilient and sustainable energy future.

“The initiative demonstrates Eskom’s commitment in finding innovative solutions and embracing new technologies in preparation for the new era in the energy distribution landscape,” the company says.

“We are pioneering the implementation of the BESS technology, serving as a large-scale commercial project to validate the technology's feasibility and benefits. The successful implementation will pave the way for wider adoption and possible export of the technology to other regions beyond the borders of South Africa,” says Velaphi Ntuli, Eskom general manager: distribution, operations enablement.

“The Hex project is a demonstration of what Eskom teams can do in finding alternative, innovative and lasting solutions in addressing the country’s electricity challenges,” says Bheki Nxumalo, Eskom group executive for generation.

Eskom notes that upon completion of the first phase, it will implement phase two of the project, which includes the installation of a further 144MW of storage capacity, equivalent to 616MWh at four Eskom distribution sites and one transmission site.

The solar PV capacity in this phase will be 58MW, it adds.

“The rollout of these technologies, together with a disciplined execution of our Generation Recovery Plan which started in March 2023, and aimed at achieving energy availability factor of 70% by end March 2025, will give the country the most needed megawatts to address capacity constraints,” it concludes.