India's largest utility, NTPC, has opened a tender for a grid-connected sodium-ion (Na-ion) battery energy storage system — the state-owned power giant's latest move to diversify beyond lithium. NTPC, which operates roughly a quarter of India's grid-connected power plants, issued invitations for expressions of interest (EOI) through its tender portal on 9 September, with submissions open until 15 October 2026. The pilot BESS will be deployed at NTPC facilities — thermal power stations or offices — and assessed on technical performance, safety, reliability, degradation, operational characteristics and techno-commercial viability.
Applicants can bid to build a pilot with 100kWh of usable capacity, or propose their own capacity. NTPC will share part of the project cost, with financial weighting based on each technology's technology readiness level (TRL). The utility said the pilot is intended to trial sodium-ion's potential for larger-scale BESS sites across its portfolio: with India currently tendering and constructing multiple gigawatt-hours of lithium-ion storage, there is a need to diversify the resource mix and reduce supply-chain dependencies.
Key facts:
- A supply-chain pivot, not just a technology pilot: LFP batteries power nearly all new BESS facilities globally, yet their supply chain is largely based in or controlled by China — and Wood Mackenzie estimates India's battery-cell self-sufficiency is at least a decade away. With limited domestic lithium resources, NTPC is looking to sodium-ion's more widely available raw materials to seed an indigenous supply chain
- A second pilot targets the last mile of the grid: In early August, the Global Energy Alliance for People and Planet (GEAPP) invited EOIs for a ~200–300kWh sodium-ion BESS with an undisclosed leading utility in North India, to be deployed at a distribution transformer (DT) site. The system must support up to two full charge-discharge cycles per day over a 12–15-year lifetime and retain ≥70% state of health at end of life. GEAPP frames DT-level BESS as "a direct intervention at the last-mile of the grid" — relieving overloaded transformers, improving feeder voltage, absorbing excess rooftop solar and cutting AT&C losses. The pilot runs under GEAPP's US$25 million India Grids of the Future Accelerator
- Demand scale: India's advanced chemistry cell demand reached 28GWh in 2025 — about 60% EVs, 40% BESS — per the India Energy Storage Alliance (IESA), which projects over 700GWh by the mid-2040s. IEEFA and JMK Research forecast battery demand growing at a 36.5% CAGR to ~272GWh by FY2030
- Not all sodium-ion is the same: The market spans four main chemistries — NFM (lowest cost, limited cycle life), NVP (high power density and structural stability, higher cost), NFPP (longevity and safety, with an energy-density trade-off) and Prussian Blue Analogues (high theoretical capacity, difficult in practice)
- NTPC's broader non-lithium track record: a 3MWh flow battery tendered in 2024 and awarded to Delectrik Systems (which was also selected for a 100MWh flow battery at the 30GW Khavda Renewable Energy Park), and a 160MWh CO2 Battery pilot with Italy's Energy Dome announced in January 2025
- Global momentum: CATL has advanced sodium-ion to mass production, and General Motors sees it as a leapfrog technology — sodium-ion uses many of the same production techniques as lithium-ion, making it a promising drop-in alternative for stationary storage
WHY IT MATTERS
- India is hedging the lithium supply chain, not waiting for it: mandating diversification through pilots while GWh-scale lithium tenders roll out is a two-track strategy that other import-dependent markets may copy.
- Distribution-transformer-level BESS is a new deployment frontier: the GEAPP pilot values local grid relief (voltage, overload, AT&C losses) — a template for last-mile storage in high-loss distribution networks across South Asia and beyond.
- Sodium-ion's commercial window is opening, with chemistry choice as the real decision: with CATL at mass production and four competing chemistries, buyers must match chemistry to duty cycle (cost vs cycle life vs energy density) rather than treat "sodium-ion" as one product.
- A market for local manufacturing is forming: with self-sufficiency a decade away and localisation pressure rising, early partnerships and local assembly will decide who supplies India's next storage wave.
THE EXLIPORC PERSPECTIVE Sodium-ion's rise matters to us for a practical reason: chemistry diversity is how buyers de-risk. EXLIPORC already ships 230Ah sodium-ion cells alongside its LFP portfolio, so distributors and integrators can quote sodium-ion and lithium-ion options from the same qualified supply base — with OEM flexibility, EU stock and direct factory support. Contact gina@exliporcpower.com or visit www.exliporcpower.com.
LINKEDIN POST India's largest utility just opened a sodium-ion BESS pilot tender. Two pilots are live (NTPC 100kWh + GEAPP 200–300kWh at distribution-transformer level) as India moves to cut lithium dependence with 28GWh of demand heading toward 272GWh by FY2030. Sodium-ion's commercial window is opening — and the real decision is chemistry, not brand. #EnergyStorage #SodiumIon #India #BESS #SupplyChain
SOURCES Energy-Storage.news, September 10, 2026 — NTPC EOI (issued 9 September, closing 15 October 2026); GEAPP EOI; IESA, IEEFA/JMK Research, Wood Mackenzie data.
