As per the updated nationally determined contribution (NDC), India now stands committed to reduce the Emissions Intensity of its GDP by 45 percent by 2030 from 2005 level and achieve about 50 percent cumulative electric power installed capacity from non-fossil-fuel-based energy resources by 2030.

Meeting these ambitious renewable energy targets requires intervention at the state level through development of integrated policies and well-thought-out capacity additions. Use of energy-planning tools can help stakeholders analyze policy alternatives to achieve suitable outcomes.

Low Emissions Analysis Platform (LEAP) is one such integrated energy planning tool that can help state-level planners visualize the impact of medium- to long-term capacity additions and retirements on the annual supply-demand energy balance, avoided capacity additions, and associated emission trends.

Executive Summary

Tamil Nadu (TN) is rich in renewable energy (RE), with the share of renewable capacity (including solar, wind, biomass, and small hydro) reaching 46 percent as of May 2022. This constitutes around 14.7 percent of the total installed RE capacity in India.

TN has huge potential of around 100 gigawatts (GW) of wind power, including 30 GW offshore wind and 17 GW of peak solar power capacity. Cumulative installed RE including wind, solar, biomass, and cogeneration is 16.46 GW (as of March 2022) with more capacity additions planned in the next eight years. However, the state also continues to add thermal capacity, with some thermal projects already in the pipeline.

TN is a highly industrialized state with a peak power demand of around 17 GW for fiscal year 2022. Daily consumption is about 340 million units and the electricity demand is expected to grow multifold, given existing plans to support domestic manufacturing and electric vehicles.

This paper explores four low carbon scenarios analyzing the impact of varying levels of RE penetration for TN's electricity sector till 2030 using LEAP.

It is observed that if the current situation continues without intervention, there is a sharp upward trend in emissions due to the high share of thermal energy generation. Hence, TN needs to start planning for phasing down or retirement of old and inefficient thermal power plants. Further, TN needs to prudently plan future capacity additions to avoid creating surplus (unutilized) capacity.

Utilities in 2030 will need to adopt an integrated planning approach that caters to changing demand by end users and varying supply trends due to increasing RE penetration levels in the electricity mix. States should deeply analyze their consumer-level demand patterns and explore the potential of demand-side energy-efficiency measures to avoid future capital investments and resultant emissions.

Such energy planning exercise could potentially inform the state in development of new policies, capital investment plans, budgets, multiyear tariff orders and decarbonization pathways.

Lessons from the TN case study can help state planners and policymakers to frame their thinking around electricity planning, considering both supply and demand options and help in identifying data gaps to enable a holistic integrated planning approach.