The Southern Regional Power Committee (SRPC) has proposed enhancing the reverse transfer capacity of the ±800kV, 6000 MW Raigarh-Pugalur HVDC system from 3,000 MW to 6,000 MW. The National Committee on Transmission (NCT) is expected to discuss this proposal in its upcoming meeting later this month.
Currently, the Raigarh-Pugalur HVDC link can transfer 6,000 MW in the forward direction from Raigarh (Chhattisgarh) to Pugalur (Tamil Nadu). The estimated cost for the reverse capacity project is around Rs 32 billion, with Rs 10 billion allocated for the HVDC system upgrade and the remaining Rs 22 billion for AC system upgrades at Raigarh (Rs 18 billion) and Pugalur (Rs 4 billion). The HVDC upgrade will be implemented by Power Grid Corporation of India Ltd (PGCIL), given it involves an upgrade of an existing PGCIL-built system and will not follow the tariff-based competitive bidding (TBCB) route.
The overall scheme, titled “Upgradation of ±800kV, 6000 MW Raigarh-Pugalur HVDC system for enhancement of reverse power capacity up to 6000 MW,” may be treated as a single comprehensive project, covering both HVDC and regional AC components. Alternatively, the AC components might be tendered under the TBCB route, pending NCT’s decision.
SRPC has recommended that PGCIL complete the HVDC upgrade within 48 months, and PGCIL has already initiated system studies expected to conclude in approximately 18 months.
This enhancement is crucial for exporting surplus generation from the Southern Region to the National Grid, especially as offshore wind farms in Tamil Nadu become operational. It also facilitates renewable energy exports from Kerala and western Tamil Nadu, as the Raigarh-Pugalur HVDC link, connected to Kerala via the ±320kV Pugalur-Thrissur HVDC link, is currently the only available corridor.
This project has been under discussion for over a year, with multiple deliberations between CTUIL, PGCIL, and transmission utilities from Kerala, Tamil Nadu, Telangana, Andhra Pradesh, Karnataka, and Puducherry. Notably, the Raigarh-Pugalur HVDC link was initially designed as a unidirectional system, with the existing 3,000 MW reverse capacity added later. Among India’s three ±800kV HVDC lines (Biswanath-Chariyali-Alipurduar to Agra, Champa-Kurukshetra, and Raigarh-Pugalur), none currently offer full reverse capacity, making this upgrade a significant step forward.