State-owned electricity utility Eskom has confirmed the award of contracts with a combined value of R4.4-billion to Hyosung Heavy Industries, of South Korea, and the Pinggao Group, of China, for battery energy storage system (BESS) projects that will be delivered across several sites by the end of June next year.

The contracts cover the lion’s share of the individual projects included as part of Phase 1 of a two-phase roll-out being funded by the World Bank, the African Development Bank, the New Development Bank and the Clean Technology Fund.

Phase 1 involves the installation of some 199 MW/833 MWh of BESS capacity across eight Eskom Distribution substation sites in four provinces. It also includes 2 MW of solar photovoltaic (PV) capacity.

Eskom will seek to implement both phases, involving 343 MW/1 440 MWh of BESS and 60 MW of solar PV, by December 2024.

It has also signalled that the initiative forms part of a larger 500 MW BESS plan, which has been included in the package of interventions unveiled by President Cyril Ramaphosa on July 25 to tackle load-shedding.

The projects to be implemented by Hyosung and Pinggao will be used primarily for peak shaving purposes for four hours a day for at least 250 days of the year. However, they will also provide some ancillary services and local network support.

It is understood that Pinggao has been awarded contracts for the 80 MW/320 MWh Skaapvlei, 9.5 MW/45 MWh Paleisheuwel and 5 MW/30 MWh Graafwater projects, in the Western Cape, while Hyosung has been awarded the 40 MW/160 MWh Pongola and the 8 MW/32 MWh Elandskop projects, in KwaZulu-Natal, as well as the 20 MW/100 MWh Hex project, in the Western Cape.

Hyosung Heavy and Pinggao have been contracted to design, supply and install the BESS systems and to provide operating and maintenance support for five years.

The utility has decided to re-tender the 35 MW/140 MWh Melkhout project, in the Eastern Cape, as well as the 1.54 MW/6.16 MWh Rietfontein project in the Northern Cape, which will include 2 MW of solar photovoltaic capacity.

Eskom tells Engineering News that the combined value of the contracts placed with Hyosung and Pinggao is R4.4-billion "roughly split in half". The second phase will cost an estimated R6-billion.

The utility also did not indicate when it expected to award the Phase 2 contracts, which cover two sites in the Western and Northern Cape provinces apiece and will comprise 144 MW/616 MWh of BESS capacity and 58 MW of solar PV.

“Through the BESS project, Eskom aspires to diversify the existing generation energy mix by pursuing a low-carbon future to reduce the impact on the environment,” coal and clean technology GM Velaphi Ntuli says, indicating that energy storage in large quantities will be required to incorporate energy from renewable sources.

“The 1 440 MWh distributed BESS with 60 MW solar PV represents a giant leap forward in achieving this aspiration, as it will be one of the largest BESS projects to be developed and implemented in South Africa.”

CEO André de Ruyter linked the BESS roll-out to Eskom’s ‘Just Energy Transition’ strategy and indicated that the utility aimed to support the development of local industry.

A preliminary BESS localisation and industrialisation study has been conducted and Eskom will continue to “engage stakeholders to ensure that maximum benefits are derived from all the project sites”.