Roadmap for Net Zero: Measures to improve Tamil Nadu’s wind energy utilisation

Tamil Nadu has achieved significant success in providing 24×7 power to all. The state is also recognised for its transformative climate action. Its power demand has historically increased at a co­mpound annual growth rate of 5 per cent. The power generation portfolio of Tamil Nadu is diversified with 36.9 GW of its total installed power capacity comprising 47 per cent renewable energy, 6 per cent hy­dro­power, 43 per cent thermal en­er­gy, and 4 per cent nuclear energy. It is one of the leaders in the renewable energy space. The power mix is largely made up of the C&I segment, which accounts for 50 per cent of demand. The domestic sector ma­k­es up the remaining 30 per cent.

Approximately 6.2 GW of power generation capacity is currently being built in the state, while nearly 13.8 GW of capacity is under various phases of development. Ta­mil Nadu has roughly 17.6 GW of solar potential and 100 GW (onshore and offshore) of wind potential. The state has installed 9.6 GW of wind energy and 5 GW of solar energy as of 2022. As a result, it has already utilised around one-third of its solar potential while only using about one-tenth of its wind potential. The rate of wind capacity development has decreased significantly of late. The state intends to build 2 GW of solar and renewable energy par­ks. In the next five years, it also plans to utilise 4 GW of offshore wind potential.

The Global Wind Energy Council has re­ce­ntly published a new report titled “Tamil Nadu Wind Energy Roadmap: Harnes­sing Net Zero Opportunities”. The report highlights that implementing a wind energy policy could help Tamil Nadu become one of the key investment destinations in Asia and provide a significant boost to the state’s economy.

Renewable Watch presents the key highlights of the report…

Wind market potential

India needs to add approximately 12.5 GW of wind capacity per year to meet its target of 140 GW by 2030. Potentially, Tamil Nadu accounts for 10 per cent of the country’s total wind generating capa­city (at a 120 metre hub height), of which 12.5 GW can be generated with a capacity utilisation factor (CUF) of more than 35 per cent. There is an urgent need for policy and regulatory interventions in the sta­te to encourage the growth of wind installations and realise the wind energy potential. To assess the state’s wind capacity ex­­pansions, three scenarios were developed in the report – low case, base case, and high case.

The low-case scenario is based on the business-as-usual case. Under this sc­e­nario, low-capacity additions would co­n­tinue. It is assumed that no specific plans or interventions will be implemented, and ramping up wind ca­pa­city will be difficult due to certain limitations. Under this scenario, Tamil Nadu would add 4 GW of wind capacity by 2030, bringing the total capacity to 14 GW.

The base-case scenario is based on capacity increase patterns at the natio­nal and state levels. Under this scena­rio, certain policy interventions will take pla­ce, eliminating some of the obstacles pre­venting capacity additions. As per this scenario, Tamil Nadu would add an additional 13 GW wind capacity by 2030, bringing the total capacity to 23 GW.

The high-case scenario is based on the premise that the state entirely removes the barriers impeding capacity additio­ns and implements different policy interventions to fully use the untapped pot­ential. According to this scenario, Ta­mil Nadu would add 25 GW wind ca­pacity by 2030, bringing the total capacity to 34 GW.

According to the base-case scenario, by 2030, Tamil Nadu will likely account for close to 16 per cent of all installed wind ca­pacity in India. In the early years, capa­city additions will be lower, but as limitations ease and policy interventions are im­ple­mented, the state will see an increase in yearly capacity additions.

Key focus areas

Tamil Nadu has over 68 GW of onshore wind power potential and over 35 GW of offshore wind power potential, according to the National Institute of Wind Energy. The state needs to give the following areas the highest priority in order to increase its wind power production capacity:

Onshore wind: The state is blessed with exceptionally high wind potential, particularly in the districts of Kanyakumari, Madurai, Tuticorin, Coimbatore, Dindig­ul, Theni, Tirunelveli and Pudikottai, am­ong others. To generate ample data for wind generation profiles and site features, more than 90 wind monitoring st­a­tions have been operationalised at various points over the past few decades. As the amount of renewable energy in the overall generating mix rises, the sta­te may use both vanilla wind installati­ons and hybrid projects to add more wind power capacities in order to maintain grid balance and energy security in the long run.

Offshore wind: In addition to enhancing other renewable energy sources, offshore wind contributes to the development of round-the-clock power and despatchable power due to its higher CUF than onshore wind. Currently, eight zon­es have been identified in the state as suitable sites for the installation of offshore wind turbines. The MNRE publi­sh­ed a draft request for proposal in Nov­ember 2022 with plans to start the state’s 4 GW offshore wind capacity auction. The auction will assist in la­un­ching the expansion of offshore wind power in Tamil Nadu. The state may ex­plore in­centivising offtakers and industrial consumers to purchase power from these installations. It could also set go­als for combining power from other technologies with offshore power in the early years. In order to support a year-round business case for ports investing in infrastructure upgrades, it is crucial to identify opportunities for capacity building, str­engthen the supply chain, and pro­­mote offshore wind manufacturing. It is also im­portant to deploy technology and un­dertake institutional interventions to track permits and clearances and im­p­rove coordination among stakeholders.

Repowering: As a pioneer in wind generation, Tamil Nadu has some of the oldest wind turbines with older technology and a lower CUF. The best locatio­ns for capturing wind energy are where many of these turbines are situated. These outdated wind turbines need to be repowered in order to make greater use of the available wind resources due to the problem of land availability. If the older turbines are replaced, they can provide a CUF of up to 30 per cent as op­posed to the current 14 per cent. According to the Government of India’s proposed repowering policy, repowering is an option for all turbines with a ca­pacity of less than 2 MW. In terms of this capacity, Tamil Nadu had over 12,000 turbines as of 2017. In the 10 years following 2022, approximately 4.1 GW of capacity can be repowered. The immediate repowering locations could be Muppandal, Poolavadi, Kethanur and Perungudi.

Nearshore wind: Tamil Nadu may also look into locations for nearshore wind farms. Nearshore wind farms have re­du­ced connection, foundation, and op­eration and maintenance expenses. The state has a long coastline, develo­ped ports, and a wind manufacturing base close to the coast that allows for nearshore installations to be made further down the coast. Similarities can be drawn with countries like Vietnam, which have conducted nearshore projects successfully.

Outlook

Tamil Nadu was one of the few states to support the early renewable energy additions and construct suitable infrastructure for evacuation. However, there has been a delay in the upgrade of the transmission system in recent years. It has been noted that the state has experienced a delay of more than five years in the projected line capacity additions. The state might concentrate on fortifying the transmission network to accommodate its expanding renewable energy capacity ex­pansions. The state could also appro­ach multilateral funding agencies and investigate purchasing power parity bid alternatives with private parties to fund the stren­g­thening of the transmission network. Furthermore, interventions are necessary to achieve large wind installations, which will maintain the state’s dominant position in wind capacity additions.

  • Stable regulatory framework: Over the course of the project, the state can provide long-term clarity on banking and wheeling arrangements. It is also necessary to promote reductions in cross-subsidy charges and wheeling charges.
  • Focus on repowering: To determine the potential, site surveys are required. Re­powered wind clusters can be combin­ed with other renewable energy so­ur­ces to integrate differently for round-the-clock/peak power and, as a result, create tariffs that reflect the economic val­ue of the system.
  • Focus on nearshore: Tamil Nadu has the capability to commission nearshore projects much faster than offshore projects.
  • Incentives for offshore: The state may consider waiving transmission, wheeling and cross-subsidy fees to encourage industrial consumers to purchase power from these plants. In addition, the state can assist in identifying offtakers and set a goal for blending throughout the early years.