Context:
In Tamil Nadu, known for pioneering wind mill installations, many turbines have surpassed 30 years of operation. In response to aging infrastructure, the Tamil Nadu government introduced the “Tamil Nadu Repowering, Refurbishment and Life Extension Policy for Wind Power Projects – 2024” in August. However, this policy has met with resistance from wind energy generators, who have successfully secured a stay from the Madras High Court. The generators are advocating for a policy that more actively promotes wind energy generation, highlighting a significant contention between industry stakeholders and state regulations.
Relevance:
GS III: Energy
Dimensions of the Article:
- What is the wind energy capacity and potential in India?
- How are wind turbines maintained?
- Repowering and Refurbishing in Wind Energy
- Way forward
What is the wind energy capacity and potential in India?
- The National Institute of Wind Energy (NIWE) says that India has wind power potential for 1,163.86 GW at 150 metres above ground level, and is ranked fourth in the world for installed wind energy capacity.
- At 120 metres above ground level, which is the normal height of wind turbines now, the potential is 695.51 GW, including the 68.75 GW from Tamil Nadu.
- Only about 6.5% of this wind potential is used at the national level and nearly 15% in Tamil Nadu.
- Gujarat, Tamil Nadu, Karnataka, Maharashtra, Rajasthan, and Andhra Pradesh are the leading States for installed wind energy capacity, collectively contributing 93.37% of the country’s wind power capacity installation.
- Tamil Nadu has seen the installation of wind turbines since the 1980s, and today it has the second largest installed wind energy capacity with 10,603.5 MW, according to data available with the Ministry of New and Renewable Energy (MNRE).
- Of the 20,000 wind turbines in the State, nearly 10,000 are of small capacities, that is less than one MW.
How are wind turbines maintained?
- Wind turbines that are more than 15 years old or have less than 2 MW capacity, can be completely replaced with new turbines, which is known as repowering. They can also be refurbished by increasing the height of the turbine, changing the blades, installing a higher capacity gear box, etc., to improve the energy generated.
- These can be done for standalone wind mills, or a group of wind mills owned by multiple generators. When wind energy generators take up safety measures in the old turbines and extend its life, its called life extension.
- The MNRE first came out with a “Policy for Repowering of the Wind Power Projects” in 2016 and based on consultations with stakeholders, released the “National Repowering & Life Extension Policy for Wind Power Projects -2023”.
- The NIWE estimates the repowering potential to be 25.4 GW if wind turbines of less than 2 MW capacity are taken into consideration.
Repowering and Refurbishing in Wind Energy
Repowering and refurbishing in the context of wind energy involve upgrading older wind turbines with newer, more efficient models or enhancing their components to improve performance and extend their operational life. This process is crucial as technology advances and the physical landscape and regulatory environments evolve.
What Does Repowering Entail?
- Upgrading Turbine Capacity: Repowering typically means replacing older, less efficient wind turbines with modern, higher-capacity units. For example, replacing sub-one MW turbines from the 1980s with newer models that can generate more electricity—such as 2 MW or 2.5 MW turbines which not only produce more power but also operate more efficiently.
- Increased Physical Requirements: Newer turbines are generally larger and require more land. A 2 MW turbine might need 3.5 acres, whereas a 2.5 MW turbine could require up to five acres. This increased size translates to higher power generation capabilities.
- Infrastructure Enhancements: Alongside turbine upgrades, infrastructure improvements are necessary, particularly regarding wind energy evacuation and transmission systems. These systems must be upgraded to handle increased power output and ensure efficient energy transfer from wind farms to the power grid.
What Does Refurbishing Entail?
- Component Upgrades: Refurbishing involves replacing or upgrading specific components of an existing turbine without a complete replacement. This might include newer blades, more efficient generators, or updated control systems.
- Extending Turbine Life: By refurbishing parts, the operational life of a turbine can be extended, making it more economically viable over a longer period, especially when complete repowering isn’t feasible due to space or regulatory constraints.
Challenges and Considerations
- Land and Regulatory Issues: As newer turbines require more space, repowering can sometimes be hindered by increased habitation around wind sites and stricter land use regulations. Additionally, the installation of larger turbines might require navigating more complex zoning laws or environmental impact assessments.
- Financial Implications: In regions like Tamil Nadu, regulatory changes such as the lack of a banking facility for new installations post-2018 affect the financial dynamics. Banking facility allows generators to store energy in the grid and use it later, offsetting times when generation exceeds immediate grid demand.
- Infrastructure Delays: Projects such as the development of sub-stations, crucial for supporting increased capacity at sites like Aralvaimozhi, often face delays due to financial, bureaucratic, or logistical challenges, impacting the overall feasibility of repowering projects.
Way forward
- Among the wind energy generating States, the repowering potential is the highest in Tamil Nadu with over 7,000 MW of installed capacity that can be replaced or refurbished. If the small turbines are repowered or refurbished, the contribution of wind energy to total energy consumed during the peak windy seasons can go up easily by 25%.
- While there have been generators which have replaced turbines in the past without government support, the policy itself does not promote wind energy generation, claim the generators.
- It should look at challenges on the field and consider how the wind energy potential can be harnessed fully by the generators.
-Source: The Hindu
