As hydrogen energy and fuel cells attract policy and investment attention across Southern Africa, battery storage systems can play a complementary role, demonstrating the need to accelerate hydrogen adoption rather than competing with it, says renewable-energy company Blockpower engineering head Timothy Mahlangu.

The region’s platinum resources, established chemicals sector and surplus renewable- energy potential provide a strong foundation for hydrogen, which remains in the developmental stage.

Meanwhile, battery storage adoption has accelerated in response to unreliable energy availability and distribution, Mahlangu says, adding that this has limitations and challenges, particularly for utilities or companies with complex and large-scale storage requirements.

The resulting gap is where hydrogen becomes critical, with battery storage and hydrogen offering value in different applications and storage durations.

Battery storage is generally most commercially competitive for short- to medium- duration applications, commonly ranging from about two to eight hours. This makes battery systems well-suited for daily cycling, frequency regulation, demand management and backup power.

However, for durations extending beyond 12 hours, conventional lithium-ion systems become less economical, particularly where the additional capacity is used infrequently or reserved for backup purposes.

Conversely, hydrogen and hydrogen- derived fuels may be particularly valuable in select heavy-transport, maritime and hard-to-electrify industrial applications.

“Although its round-trip efficiency is lower than that of batteries, duration and storage capacity become more important when the alternative is curtailing or wasting renewable energy,” Mahlangu says.

Given these contrasting strengths, he expects hydrogen development to concentrate on industry, transport and export, while batteries remain the primary stationary storage solution for commercial and industrial applications.

Additionally, as costs decline and local supply chains mature, Mahlangu expects hybrid systems – that combine batteries, for rapid response, with hydrogen, for extended resilience – to gain traction, particularly at remote and offgrid industrial sites.

In the interim, battery storage is the practical bridge to the green economy, closing the gap between intermittent renewables generation and electricity demand, he says.

While providing various advantages in comparison to carbon-based energy, solar only produces energy during daylight hours while wind output fluctuates.

Consequently, renewable generation may be curtailed where production exceeds demand, storage capacity or available grid-export capacity.

Battery storage helps address this challenge by shifting surplus renewable energy to periods of higher demand, reducing reliance on diesel generators, limiting exposure to grid instability and combining resilience, cost savings and decarbonisation in a “single bankable solution”.

Ensuring Stability
Initially functioning primarily as advanced uninterruptible power supply systems to provide short-term backup during outages, battery storage has since evolved into a strategic energy management asset, supporting peak shaving, time-of-use arbitrage, renewable integration and demand response.

This shift was driven by significant loadshedding in 2022 and 2023, combined with a substantial decline in lithium-iron-phosphate (LFP) battery costs.

The market has increasingly adopted repeatable system configurations, bankable manufacturer warranties, experienced local engineering capability and dedicated insurance products.

Mahlangu points out that in energy-stable markets, battery storage is a financial optimisation tool, which limits the urgency or willingness of these markets to enter into long-term energy service agreements at scale.

However, in South Africa, battery storage has become essential infrastructure.

This creates a strong sense of urgency, shortens perceived payback periods and increases demand for zero-capital-expenditure solutions such as Blockpower’s Energy-as-a-Service model.

Industry Developments
LFP has become the dominant chemistry across commercial, industrial and utility-scale applications owing to its significant thermal stability, longer cycle life and the absence of cobalt.

Meanwhile, vanadium redox flow batteries suit long-duration, grid-scale applications where extended cycle life and electrolyte longevity can justify its higher capital costs. While interest in batteries is growing, the market remains limited, Mahlangu says.

Despite the advances in battery technology, several regulatory reforms are required to boost storage deployment in South Africa.

He emphasises that the most urgent reform is a standardised, time-bound grid connection framework with clear technical requirements and enforceable approval timelines across State-owned electricity utility Eskom and municipal distribution areas.