How New Technologies Could Enable Tamil Nadu to Transition to Cleaner Energy

Tamil Nadu has the highest capacity of installed wind energy in India (9.6 GW as of March 2021² ) due to its resource-rich locations, favorable policies, and early adoption. After Karnataka, Tamil Nadu has the second highest installed capacity of renewable accounting for nearly 45 percent. The recently elected ruling party assured power production and distribution on a “wartime basis” in its election manifesto³ . The Dravida Munnetra Kazhagam (DMK) government led by Chief Minister MK Stalin has also taken initial steps to follow⁴ up on its promise to produce 20 GW of renewable energy by signing an agreement with Indian Renewable Energy Development Agency (IREDA).

Repowering old windmills is also on the state government’s agenda with a promise to install new ones at the site where deteriorated ones exist now. Tamil Nadu has issued three policies⁵ regarding renewable energy since 2019 - Tamil Nadu Solar Policy, 2019; (ii) Tamil Nadu Electric Vehicle Policy, 2019; and (iii) Tamil Nadu Industrial Policy, 2021. An enabling environment for new technologies is one way of ensuring policy success.

Let us start with the wind sector. The main hurdle in this sector is ageing and low-capacity turbines, which occupy the best wind sites. The wind turbines installed in the early ‘90s were mostly of unit capacities less than 1 MW. Apart from replacing old windmills, Tamil Nadu could plan to repower some of them with new wind turbine models that use modern technology. Repowering could involve revamped infrastructure including higher efficiency wind turbine sizes, changes to the generators, blades, electrical equipment, and foundations. Along with suitable policy support and guidelines for the safe disposal and recycling of decommissioned machines, the state could add much more wind power capacity to the energy mix this way.

Second, Tamil Nadu is blessed with great potential for offshore wind power production. Its coastline is over 1,000 kilometers long - about 15 per cent of India’s entire shoreline. According to scientists at the National Institute of Wind Energy (NIWE), this gives the state an estimated 35 GW of potential wind power capacity⁶ . Enhanced LiDAR^,1 data accuracy, digitization, building interconnectors to strengthen the grid, exploring green hydrogen and energy storage solutions could help in accelerating the growth of offshore wind energy in the state.

Third, Tamil Nadu’s installed solar capacity is just around 4.5 GW⁷ , as of March 2021.This is only 2 percent of the estimated potential of 279 GW for the state. High potential in the state along with technological advancements enable it to allow exploring alternative options such as perovskite, polymer based, nanocrystal based, dye-sensitized (DSSC), concentrated, and transparent solar cell technologies.

Considerable advances have also been made in technologies and solutions that help integrate solar PV into the grid. One example is bifacial solar cells which can harvest solar energy from both sides of the cells, augmenting power output by 10-30%. Most developed third generation solar cell types are dye sensitized and concentrated solar cells. DSSC are based on dye molecules between electrodes. They are cheaper but they come with lower efficiency. On the other hand, perovskite solar cells (PSCs) have gained more traction due to their lower price, thinner design, low-temperature processing, and excellent light absorption properties. PSCs perform well even under low and diffused light. Combined perovskite and Si-PV materials have shown a 28% efficiency⁸ under laboratory conditions.

Fourth, implementing energy storage systems is seen as a solution to not just manage the intermittency in high RE-rich states like TN but also to provide ancillary support. Lithium-ion batteries have witnessed tremendous interest over the last few years due to suitability in various applications in electronic devices and electric vehicles. Nevertheless, there is benefit in exploring various storage technologies beyond Lithium ion. This could include green hydrogen storage, solar thermal, redox battery solutions, and gravity storage.

In India the hydrogen energy market is expected to increase with 6.3% CAGR from 2018 to 2025⁹ . The share of hydrogen in the energy market is increasing with the implementation of fuel cell systems. Surplus RE power can be utilized to produce green hydrogen which in turn can be used for multiple applications. Currently, there is no operational grid scale battery storage plant or hydrogen storage facility in Tamil Nadu. This is certainly an area that needs focus, especially with the state’s plans to increase RE capacities.
 

Way Forward
We do realize that there are barriers to the adoption of these new technologies. Most of the high-efficiency technologies are at the early stages of research and lack maturity. A working paper from the International Renewable Energy Agency (IRENA), shows¹⁰ integrating new and matured technologies such as green hydrogen, offshore wind, and energy storage along with hybrid RE systems could help in augmenting renewable resources. Given Tamil Nadu’s large untapped renewable resources potential, such integrations could be attempted.

For this to happen, cross learnings from success stories and case studies globally through effective industry-academia collaborations are required. For niche applications especially for already established markets, policy planners should work with Industries to identify the gap and address them. Tamil Nadu’s demographic advantage with a young workforce could also be leveraged to impart skills in specific technologies at the local and the state level. Setting up local manufacturing capabilities and skill development could help in increasing operational efficiency.

Enabling policies should be holistic by integrating new technologies with renewable capacity addition plans. For seamless implementation, execution and timely deployment is essential where roles of stakeholders are defined based on the type of technology, market readiness, innovation, and target sectors (commercial, industrial, transport, etc). This would require a concerted and coordinated effort between utilities, industry players, especially start-ups, research bodies, and renewable development agencies.

In the early stages of technology development, it is advisable to have a forum, which brings government, business, and private sector together. They must enable “market push” to move to “market pull”.

Finally, utilities and policy makers must look at scientific frameworks to arrive at realistic integrated solutions for these complex energy problems. New technologies must be part of the solution rather than being completely new systems. This would allow for their full potential to be realized.
 

- Sandhya Sundararagavan, Lead - Energy Transitions Energy Program , WRI India

- Kajol, Manager, Energy Program, WRI India
 

^{References
1.} Lidar, which stands for Light Detection and Ranging, is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth.The lidar unit collects a range of measurements, including the critical offshore wind data
^2. https://mnre.gov.in/wind/current-status/
^3. https://dmk.in/dmk-manifesto-english-2021
⁴.https://www.business-standard.com/article/current-affairs/tamil-nadu-plans-23-000-mw-renewable-3-000-gas-projects-over-10-years- 121090601252_1.html
^5.https://www.thehindubusinessline.com/opinion/tn-well-placed-for-clean-energy-transition/article34783100.ece
^6. https://niwe.res.in/assets/Docu/India’s_Wind_Potential_Atlas_at_120m_agl.pdf
^7.  https://mnre.gov.in/solar/current-status/
^8.  https://www.nature.com/articles/d41586-019-01985-y
^9.https://www.alliedmarketresearch.com/india-hydrogen-market#:~:text=The%20India%20hydrogen%20market%20was,
industry%20to%20refine%20crude%20oil
^10.https://www.irena.org/publications/2017/Jun/Accelerating-the-Energy-Transition-through-Innovation