Discuss the role of Battery Energy Storage Systems in addressing intermittency and curtailment in India's power grid. What policy measures has the government taken?

Battery Energy Storage Systems (BESS) store surplus electricity and release it when it is needed. Solar and wind make up 37% of India's installed capacity but produce only 13% of its electricity [2]. Much of that gap comes from intermittency, so BESS is key to turning renewable energy (RE) capacity into reliable power.

Role in addressing intermittency

• Time-shifting: stores midday solar power and supplies it at the evening (non-solar-hour) peak [1].
• Grid flexibility: batteries respond quickly, which smooths sudden drops in wind or solar output and helps keep the grid stable.
• Firm RE supply: RE combined with storage lets DISCOMs sign round-the-clock supply contracts.

Role in addressing curtailment

• Absorbs surplus: at peak solar hours, clean power that the grid cannot absorb is otherwise wasted (curtailed). BESS stores it instead [1].
• Eases congestion: batteries placed at the RE generator's end relieve crowded transmission lines [1].
• Decarbonisation: 4,000 MWh of BESS is expected to cut about 1.3 MMT of carbon emissions a year [7].

Limitations

• Scale gap: assuming 4-hour batteries, 50 GWh can supply about 12.5 GW for four hours. That is small next to the up to 135 GW of RE the new lines are meant to carry.
• Data and revenue gaps: NITI Aayog notes there is no transparent curtailment data, and some regulations restrict how storage can earn revenue [3].

Policy measures

• VGF for BESS (2023): Viability Gap Funding covers up to 40% of capital cost, with budgetary support of Rs 3,760 crore [4].
• Scale-up: two VGF schemes (March 2024 and June 2025) support about 43 GWh. VGF per MWh fell from Rs 96 lakh to Rs 46 lakh as battery costs dropped [5].
• DISCOM priority: at least 85% of power from VGF-funded BESS must first be offered to DISCOMs [6].
• PLI for ACC batteries: Production Linked Incentive for 50 GWh of Advanced Chemistry Cell manufacturing, including 10 GWh for grid-scale storage [5].
• PM-DHARA (2026): 50 GWh BESS (Rs 50,000 crore) combined with intra-State transmission for up to 135 GW of RE under GEC-III, to be completed by FY 2032-33 [1].

BESS turns variable renewable energy into power that can be supplied on demand. Policy has moved from standalone viability-gap support to planning transmission and storage together. Next steps should be to publish curtailment data, pay storage for the services it gives the grid, and adopt time-of-use tariffs [3]. Together with pumped storage, these steps would support the 900 GW non-fossil target by 2035 [1] and SDG 7.