Flow batteries are electrochemical devices that store electrical energy in liquid electrolytes and convert it back to electricity when needed. As countries work expand renewable energy and strengthen electricity systems, long-duration energy storage technologies are becoming increasingly important. Among these, flow batteries are attracting growing interest for their potential to provide reliable, zero-emission electricity. Although flow batteries currently represent a relatively small market, they offer significant potential for future deployment and local manufacturing in many developing economies.

About the study

In 2025, the Faraday Institution commissioned a study to assess the performance of different flow battery technologies and evaluated their potential contribution to clean energy transitions in emerging economies. Funded by the UK government through the Transforming Energy Access (TEA) platform – recently extended to 2031 as part of the Ayrton Fund – and supported through the GRTD portfolio’s growth, energy and infrastructure pillar, the report was written by Foresight Transitions Ltd, with Swanbarton Limited and the University of Southampton.

The study examined how flow batteries could be used as grid-scale energy storage, replacements for diesel back-up generators, and to supply electricity to off-grid communities. It also explored opportunities for local manufacturing.
The report is intended for power system developers, mining and industrial facility operators, data centre owners, energy storage professionals, and battery manufacturers in developing economies.

What the report found

The study found that flow batteries vary considerably across different technology types. For example, vanadium flow batteries are the most proven option in commercial settings. Other types, including hybrid metal plating flow batteries, such as zinc/bromine, lead, iron, and lithium/polysulfide, offer many advantages, with the key technical challenge being the demonstration of adequate lifetime, due largely to limited large-scale demonstrations.

Among the countries assessed, South Africa, Indonesia, Thailand and India were identified as the most promising markets for flow battery deployment. The report found several sectors where flow batteries could provide value, including mining, industrial facilities and data centres. Many of these applications require energy storage duration of between 4 to 12 hours, which aligns well with the performance characteristics of vanadium and hybrid metal-plating flow battery technologies.

The report found more limited opportunities in residential and small community-scale applications. However, important exceptions exist in region with significant numbers of isolated or island communities in Southeast Asia and the Pacific, where electricity systems often rely heavily on diesel-powered generation.

One of the study’s key findings is that flow battery manufacturing may be well suited to developing economies, as flow battery manufacturing can be developed incrementally. Production can begin with simpler components and scaled up gradually to higher-value parts, making it more accessible for emerging markets. India, Thailand, Malaysia, and South Africa show the strongest near-term manufacturing potential.

UK-funded research in action

The Ayrton Fund has also supported practical development of a low-cost soluble lead flow battery by researchers at the University of Southampton. A small demonstration system has already been built and tested, which contributed to the creation of a spin-out of a company, SOLead Energy, file a patent application, and start IP licensing negotiations. A demonstrator project is in progress with the University and partner Gham Power in Nepal.

Find out more

The full report, Market and Technology Assessment of Flow Batteries for Developing Economies, is available to download. A supporting webinar presenting the main findings is also available.