Why in news?
On 11 November 2025, India’s National Thermal Power Corporation (NTPC) inaugurated the country’s first megawatt‑hour‑scale Vanadium Redox Flow Battery (VRFB) at its research facility in Noida. This demonstration system, with a capacity of about 3 MWh, will test how large batteries can store renewable energy for long periods and release it when needed.
Background on vanadium
Vanadium is a silvery‑grey metal with the chemical symbol V and atomic number 23. Discovered in the early nineteenth century, it is found in over sixty minerals, as well as in certain coals and crude oils. Large reserves exist in South Africa, Russia and China, and these countries dominate global production. The element resists corrosion and improves the hardness and strength of steel when added in small amounts. Vanadium compounds also serve as catalysts in the manufacture of sulphuric acid and other chemicals. In recent years vanadium has gained attention for its role in advanced energy storage systems.
What is a vanadium redox flow battery?
- Electrolyte chemistry: A VRFB stores energy in liquid electrolytes containing vanadium ions in different oxidation states. Two tanks hold these electrolytes, which flow through a cell stack where they exchange electrons across a membrane.
- Separation of power and energy: The size of the cell stack determines how much power (kW) the battery can deliver at one time, while the volume of electrolyte tanks determines the total energy capacity (kWh or MWh). This allows designers to scale power and energy independently.
- Longevity and safety: Because vanadium ions remain stable and the electrolytes do not degrade significantly, VRFBs can cycle tens of thousands of times with minimal loss of capacity. They are non‑flammable, making them safer than lithium‑ion batteries for stationary applications.
- Suitability for renewables: These batteries are ideal for storing solar and wind energy, which fluctuate throughout the day. They can deliver power over several hours, helping to balance supply and demand on the grid.
Benefits of the project
- Energy transition: By demonstrating long‑duration storage, India can integrate higher shares of renewable power and reduce reliance on fossil‑fuel plants.
- Domestic innovation: The project encourages research into electrolyte synthesis, battery manufacturing and recycling of vanadium, which could foster a home‑grown supply chain.
- Scalability: If successful, VRFB technology could be deployed at solar parks, wind farms and industrial sites across India, supporting the government’s goal of achieving net‑zero emissions.
Sources: Evertiq,Britannica