NTPC Limited has issued a global Expression of Interest (EOI) to develop a pilot grid-connected Battery Energy Storage System (BESS) using sodium-ion battery technology. The initiative, announced through EOI reference NTPC/PE/ET&PR/EOI-06/2026-27 dated September 9, 2026, seeks technology providers capable of demonstrating and evaluating sodium-ion energy storage performance under Indian operating conditions.
The pilot project is proposed to be installed at existing NTPC thermal power stations or NTPC office buildings. Through the project, NTPC intends to evaluate the technical performance, safety, reliability, and commercial viability of sodium-ion battery technology for energy storage applications.
The initiative comes as India rapidly expands solar and wind power capacity, increasing the need for reliable energy storage to support grid stability, renewable energy integration, and demand management. Lithium-ion batteries currently dominate the BESS market, but India remains significantly dependent on imports for lithium and other critical battery materials. Sodium-ion technology is being considered as an alternative because sodium is abundantly available and could support greater domestic supply-chain development.
Under the EOI, applicants are required to submit technical and financial proposals for two pilot options. Option 1 involves a standardized BESS with 100 kWh of usable energy capacity, providing a common basis for comparing different technologies. Option 2 allows applicants to propose a suitable BESS capacity based on the scale required to demonstrate their technology.
The proposals will also be assessed according to Technology Readiness Levels (TRL). Applicants offering technologies at TRL 4 or TRL 5 will be required to contribute at least 50% of the total project cost. NTPC may return this contribution after successful completion and demonstration of the pilot, subject to mutually agreed terms. For technologies at TRL 6 and above, no minimum financial contribution is mandatory. However, NTPC will give preference to applicants offering a higher financial contribution.
NTPC will provide land within its premises, incoming feeder points at a 415 V LT switchgear, auxiliary power supply, and assistance with statutory approvals. The selected applicant will be responsible for the complete design, manufacturing, supply, erection, testing, commissioning, safety and fire suppression systems, and comprehensive maintenance of the BESS for three years.
The owner of the technology will retain the intellectual property rights to the fundamental technology. The applicant and NTPC will jointly hold any unique intellectual property created during the pilot’s execution.
While EOI submissions must be made by October 15, 2026, the deadline for requesting clarifications is October 5, 2026. The responses will be accepted for six months after the submission date, starting on October 16, 2026.
At this EOI stage, neither an Earnest Money Deposit nor a Performance Bank Guaranty have been defined. Instead of rapid commercial acquisition, the project is concentrated on partnership building and technological evaluation.





