India Pilots Battery Storage at Coal Plants to Stabilise Solar, Boost Grid Flexibility

Experimentation at the Crossroads of Coal and Renewables

India is pioneering an innovative approach to grid management by launching pilot battery storage projects directly at coal-fired power plants. This initiative aims to address a critical challenge facing the nation’s rapidly expanding solar sector: how to balance surplus solar generation with the stable, on-demand power coal plants have long provided.

The National Thermal Power Corporation (NTPC), India’s top thermal generator, is leading initial trials with funding support from the central government. The pilot will see large-scale batteries installed at coal station sites, capturing excess solar power during low-demand hours and dispatching it during periods of peak need—especially in the evening, when solar drops off and demand soars.

Why Is This Needed?

As solar power floods the daytime grid, conventional coal plants are required to ramp down or even temporarily halt operations. Since thermal units aren’t designed for quick shutoffs or frequent cycling, this wastes fuel, increases costs, and accelerates equipment wear. Without stable support from baseload generators, grid reliability can suffer, risking power shortages when the sun sets.

India’s Central Electricity Authority (CEA) has acknowledged the difficulty, setting out new guidelines for minimum technical operation of coal units as renewables grow. Battery energy storage is viewed as a potential “shock absorber” to preserve thermal fleet reliability while maximising solar’s contribution to the grid.

NTPC's Pilot and the Broader Market

The NTPC’s programme involves testing high-capacity batteries at select coal plants, a first for India. The batteries absorb excess power, store it, and then dispatch electricity during evening peaks without forcing the coal plant into unstable operating patterns. By maintaining more consistent output from coal units, stations save on fuel and maintenance costs, extend asset lifespan, and can better support the national grid.

In parallel, NTPC has issued tenders for 1.7 GW of battery storage across 11 coal plants—underscoring how seriously the proposal is being considered.

The Rise of Merchant Battery Energy Storage

Beyond the coal-linked trials, India’s energy storage sector is experiencing its own commercial revolution. A new market segment—”merchant” Battery Energy Storage Systems (BESS)—has begun turning a profit in 2024. These BESS units buy power during low-price periods and sell it back when demand (and prices) spike, similar to an electricity stock market.

This shift is driven by falling battery costs and heightened price volatility, making storage a lucrative business even without fixed long-term contracts. The broader lesson: batteries are now central to the evolving business of power as well as its technical operation.

The Long-Term Grid Vision

A 2021 IEA report forecasts India’s coal capacity will plateau in the next five years while solar capacity could reach a staggering 800 GW by 2040. By then, coal and solar’s shares in power generation are expected to be nearly even, with renewables emerging as the main driver of India’s electricity supply.

Pilot battery storage at coal plants is part of a strategy to future-proof the grid—ensuring legacy infrastructure remains relevant and reliable as the country accelerates toward its 500 GW non-fossil ambition by 2030.

Policy, Industry, and International Parallels

The experiments align with global trends as nations seek to balance intermittent renewables with traditional grid anchors. The success of India’s pilots could establish a replicable model for other economies dealing with rapid energy transition and entrenched coal dependence.

Strong policy coordination, innovative market design, and ongoing investment in grid upgrades and storage capacity remain critical. As the CEA and Ministry of Power refine guidelines, power utilities are positioned to make storage a pillar of India’s clean energy matrix.

Conclusion

India’s coal-plant battery storage pilots are a crucial experiment in harmonising old and new technologies. Their success could offer a blueprint for grid-stable decarbonisation, maintaining reliability without sacrificing India’s solar ambitions.