Context
Recently, the Union Ministry of Environment, Forest and Climate Change granted Terms of Reference (ToR) clearance to the proposed 1,100 MW Velimalai Pumped Storage Hydroelectric Project in Tamil Nadu’s Kanniyakumari district, aimed at improving energy storage and supporting renewable energy integration.
About Velimalai Pumped Storage Hydro Electric Project
- The project is proposed at Vellimalai to strengthen peak power supply and facilitate greater integration of renewable energy into the electricity grid.
- It will be developed as a closed-loop off-river pumped storage system, where water will circulate between two artificially created reservoirs with minimal dependence on natural river inflows.
- The project will include an underground powerhouse comprising four hydroelectric units of 275 MW each.
- Two off-river reservoirs are planned under the scheme. The upper reservoir will have a gross storage capacity of about 4.39 million cubic metres, while the lower reservoir will store nearly 4.91 million cubic metres of water.
- The lower reservoir is proposed upstream of the existing Mambazhathuraiyar Dam in the region.
- During off-peak hours, surplus electricity will be used to pump around 3.94 million cubic metres of water to the upper reservoir over nearly 6.94 hours.
- The stored water will later be released during periods of high electricity demand, with electricity generation planned for nearly six hours daily.
- The project is expected to generate around 2,080.55 million kWh of electricity annually.
- It will be the first pumped storage hydropower project in Tamil Nadu to be implemented under the Public-Private Partnership (PPP) model on a Build-Own-Operate-Transfer (BOOT) basis under Section 63 of the Electricity Act.
