Tamil Nadu Clears 34.75 MW Hybrid Wind–Solar Project Under Repowering Plan

The Tamil Nadu Electricity Regulatory Commission (TNERC) has approved a proposal from the Tamil Nadu Green Energy Corporation Ltd. (TNGECL) and the Tamil Nadu Power Distribution Corporation Ltd. (TNPDCL) to float a tender inviting developers to set up a cumulative of 34.75 MW solar and wind projects. These projects are a part of the state's repowering plan to develop 18.75 MW of wind and 16.0 MW of solar projects.  

Following requests from TNPDCL and TNGECL, TNERC approved the petition, enabling the corporations to issue tenders under the Tariff-Based Competitive Bidding Build, Own, and Operate (TBCB-BOO) model.

The tender will invite applications for developing a combined renewable power plant comprising 18.75 MW of wind and 16 MW of solar PV capacity. The project will be established across wind farm sites located at Kayathar-I and II, Puliankulam, and Muppandal villages in the southern districts of Tamil Nadu.

The initiative aims to bridge the shortfall in wind power generation required to meet the Renewable Purchase Obligation (RPO) targets. In FY 2025–26, the installed capacity commissioned after March 31, 2024, was 320 MW. Over the past decade, the year-on-year (YoY) addition in wind capacity has averaged around 300 MW. Accordingly, the projected YoY capacity addition from FY 2025–26 to FY 2029–30 has been estimated at 300 MW.

TNERC has also approved the implementation of a Power Sale Agreement (PSA) between TNGECL and TNPDCL, with a trading margin of three paise per unit, subject to the Commission’s approval of tariff adoption.

The regulation will help Tamil Nadu partially meet its growing power demand while fulfilling RPO commitments under the Resource Adequacy Plan.

Repowering Wind Projects

Based on the recommendations of the Sub-Committee and discussions with the Tamil Nadu Infrastructure Development Board (TNIDB), TNERC accepted the proposal approved by the TNGECL Board to execute the repowering of the 18.75 MW wind and 16 MW solar projects.

The Commission also approved adopting the TBCB-BOO model instead of the TBCB-BOOT model, which had been approved earlier in TNGECL’s sixth Board meeting.

The proposal further reduces the Earnest Money Deposit (EMD) requirement from 2% to 1% for this project. It includes provisions for decommissioning old windmills, a responsibility that will rest with the successful bidder, who must bear the dismantling expenses.

According to the cost analysis, the levelised tariff for the proposed repowering wind–solar hybrid project—excluding capital costs related to land and evacuation infrastructure—has been calculated at ₹2.93 per unit for 25 years.

Additionally, the Commission noted that the repowering guidelines and government policies issued by the Ministry of New and Renewable Energy (MNRE) encourage incorporating all project lifecycle costs, including the dismantling of old assets, within the per-unit tariff. This approach aims to promote transparency, accountability, and accurate cost discovery.

About the Petition

TNPDCL and TNGECL jointly filed the petition to develop a 34.75 MW hybrid renewable energy project, comprising 18.75 MW of wind and 16 MW of solar capacity.

The hybrid project will be implemented across four existing Wind Energy Generator (WEG) project sites, most of which are currently non-operational and have been decommissioned. Among these sites, Kayathar-I, Kayathar-II, and Muppandal are owned by the Tamil Nadu Energy Development Agency (TEDA), while the Puliankulam site is under TNGECL’s control.

TNGECL, acting as the Bid Process Coordinator and Intermediate Procurer, will execute a 30-year lease agreement for the three project sites—Kayathar-I, Kayathar-II, and Muppandal—owned by TEDA. These sites will be sub-leased by TNGECL to the successful developers selected through a reverse e-bidding process for 27 years. The Puliankulam site, controlled by TNGECL, will be leased directly to the successful bidder for the same duration. The lease rent has been fixed at ₹1 per year, plus applicable taxes.

ViewPoint

The Tamil Nadu move appears to be timid and showing lack of imagination. Wind energy generation started in Tamil Nadu from 1986 with the machine  capacity ranging from 55 KW to 250 KW, and as a pilot study, the TNGECL in joint  venture with TEDA and MNRE, had erected 110 Nos. of smaller capacity, totalling to  17.355 MW of wind turbines in wind farm sites at Kayathar-I and II, Puliyankulam,  Muppandal villages in Tuticorin and Tirunelveli Districts, and Kethanur village in  Coimbatore District. These wind turbines were commissioned from the year 1985 to  1992 in various stages in technical collaboration with the Danida Energy Agency, the  Danish Government. Out of the above 110 Nos of wind turbines installed, only 15 Nos of wind turbines  are currently in running condition and the remaining 95 Nos of WEGs are not in running  condition and are condemned since OEM companies are no more in Industry to supply  spares and to take of the O&M activities. With these turbines more than meeting their purpose, it is incredible to see the state agencies seek permission or plan for such a small effort at wind repowering when capacity of existing and futue turbines in the market are at 3 MW and over per turbine. Tamil Nadu is sitting on a wealth of wind resources that are powered by sub -optimal turbines of less than 500 kW, where the state needs to make a plan to repower afresh. Showing a little ambition and imagination could helpo the state easily achieve its RPO goals and more at a much lower cost.