Large-Scale Battery Storage Project: How Tamil Nadu is Leading India’s Renewable Energy Storage Revolution

Tamil Nadu’s Groundbreaking 500 MWh Battery Storage Project
In a significant move towards sustainable energy, Tamil Nadu Green Energy Corporation Limited (TNGECL) has awarded NLC India Renewables Limited (NIRL) the contract to develop a 500 MWh Battery Energy Storage System (BESS). This is the state’s first large-scale battery storage initiative under its new energy storage policy, marking a major shift towards reliable and clean power management.

Key Highlights of the Project
Capacity & Locations:
Total capacity of 250 MW / 500 MWh (supporting two full charge-discharge cycles daily).
Three standalone projects will be set up at:
Ottapidaram Substation (400/230/110 kV)
Annapankulam Substation (400/230/110 kV)
Kayathar Substation (400/230/110 kV)

Funding & Support:
Backed by the Central Government’s Viability Gap Funding (VGF) Scheme, covering 30% of the capital cost.
Tamil Nadu is among six states (including Gujarat, Karnataka, and Maharashtra) selected for BESS development.

Operational Model:
Build-Own-Operate (BOO) model under a 12-year agreement.
Tamil Nadu Power Distribution Corporation will procure stored energy from NIRL.

Why This Project Matters
Stabilizes Renewable Energy Supply:
Solar and wind power are intermittent—BESS stores excess energy for use during nights or cloudy days.
Reduces reliance on fossil fuels during peak demand.

Cost & Grid Efficiency:
Maximizes transmission line usage even when renewable sources aren’t generating power.
Lowers electricity costs by optimizing stored clean energy.

Future Expansion Plans:
Tamil Nadu aims to install 1,000 MWh under the state VGF scheme, with long-term plans for 4,000 MWh.

What Experts Say
A TNGECL official explained:
“Renewable energy isn’t steady, causing grid integration challenges. BESS ensures we use transmission lines efficiently, even when solar/wind power isn’t available.”
The stored solar energy will also help meet evening peak demand, reducing costs and supporting Tamil Nadu’s low-carbon growth goals.


Sample Questions & Answers (For Competitive Exams)
Q1. Which company has been awarded Tamil Nadu’s first large-scale BESS project?
A1. NLC India Renewables Limited (NIRL).
Q2. What is the total capacity of the BESS project in Tamil Nadu?
A2. 250 MW / 500 MWh.
Q3. Which government scheme supports the funding of this project?
A3. Viability Gap Funding (VGF) Scheme, covering 30% of the capital cost.
Q4. How long is the energy storage purchase agreement valid?
A4. 12 years.
Q5. Name one substation where the BESS will be installed.
A5. Ottapidaram Substation (400/230/110 kV).