The South African electricity grid is entering a phase where stability is less about how much power is generated and more about how power can be effectively managed and controlled. For global electrification company Hitachi Energy, the priority has shifted from adding capacity to using storage and power electronics solutions to manage grid disturbances and system fluctuations, strengthening the grid and providing a reliable power supply.

Speaking at Electra Mining Africa 2026, held at the Nasrec Convention Centre, in September, Hitachi Energy sub-Saharan Africa grid and power quality solutions sales manager Gnana Sekaran said the company’s main objective was grid stabilisation, sustainability and customer convenience.

“We are doing a lot in battery energy storage systems (BESS),” he said.

Hitachi Energy delivers end-to-end BESS solutions designed to support grid-following and -forming operations, which allows for voltage and frequency control, and facilitates system strength and grid restoration.

He added that Hitachi’s system’s modular building blocks allowed for scalable mega- watt and megawatt-hour configurations for applications ranging from local energy hubs to multi-gigawatt utility-scale systems.

“What we do in BESS is target segments that are 10 MW to 100 MW, but we have been open to projects of a larger scale, such as our commissioned work in Australia, where we installed [an 800 MW] BESS.”

BESS enhances grid resilience by smoothing fluctuations caused by demand-related strain, stores energy during periods of excess generation and reduces reliance on fossil fuels while creating capacity for more clean energy projects, he elaborated.

For peak shaving, BESS also reduces energy costs by discharging stored power during peak demand. When renewables are integrated, BESS acts as a buffer for the intermittent nature of solar and wind resources, storing excess energy and releasing it when generation drops, stabilising the grid.

“From a medium-voltage switchgear, a client can either draw power and be a consumer or, when there is excess power, export excess energy to the grid.”

Sekaran further noted that Hitachi Energy, over the past few years, has been developing high-voltage substations in a modular format, instead of conventional on-site solutions.

The high-voltage modular substations will be fabricated, preinstalled and assembled in the factory and transported to the site, ready to connect to the grid. This reduces the overall site installation activity by 70% to 80% and contributes to a significant reduction in project delivery timeline.

Meanwhile, for small- to medium-sized companies, including mines that rely heavily on diesel generators, Sekaran said Hitachi Energy is working on a “sustainable and cost-effective- in-the-long-term” alternative.

“Many small- to [medium-sized] companies today rely mostly on diesel generators which are harmful to the environment. The running costs are also high – almost to the tune of  R0.30/kWh to R0.40/kWh.”

The Hitachi Energy HyFlex is a hybrid generator and flexible power hub that combines hydrogen fuel cells, batteries and power electronics, providing zero-emission electricity for temporary and off-grid applications such as construction and mine sites, added Sekaran.

He emphasised the environmental benefits, noting that the unit produces electricity through electrochemical processes, eliminating pollutants, such as CO2, nitrogen oxides and particulate matter, unlike diesel generators.

The system combines hydrogen fuel cells with high-performance batteries with the option to incorporate other power sources.

A 200 kVA HyFlex unit can displace up to 300 t of diesel yearly and prevent an estimated 1 000 t of CO2 emissions, while a 1 MVA diesel generator running at full load combusts about 225 kg of diesel and emits 720 kg of CO2/h by comparison.

“An Africa-based pilot project [for the HyFlex unit] is in the pipeline,” Sekaran concluded.