Solar Energy Potential: Tamil Nadu

Solar energy potential in Tamil Nadu is rooted in the effective use of the state’s land resources. Analysis shows that Tamil Nadu’s geographical spread includes both cropland and unused land, which together represent a major opportunity for sustainable energy expansion. The state has set an ambitious solar energy target of 20 GW by 2030, which can be achieved by focusing on these available land categories. Unused land accounts for a sizable share of the total area, and cropland covers an even larger portion, making both sectors critical in planning for renewable energy development.

Unused Land and Cropland: Mapping the Opportunity

Tamil Nadu’s total geographical area comprises 130,325 km². Unused land covers about 33,274 km² (approx. 25.7%), while cropland spans 45,921 km² (around 35.5%). Combined, they make up over 60% of the state’s geographic area.

• Unused and fallow lands offer rapid opportunities for ground-mounted solar projects due to ease of aggregation and lower land-use conflict.
• Cropland can be leveraged using Agri-PV systems, allowing for dual use—agriculture and solar energy production.

Both categories exceed the required area to meet the state’s 20 GW solar capacity goal. Technical analysis suggests up to 150 GW solar potential for unused land and 149 GW from cropland, offering surplus capacity well beyond policy targets.

Suitability Assessment: Criteria and Approach

The suitability analysis for solar projects incorporates multiple criteria:

• For unused land: Minimum size of 5 acres, average solar irradiance above 4.5 kWh/m²/day, proximity (within 5 km) to transmission infrastructure, and exclusion from legally protected, environmentally sensitive zones.
• For cropland: Minimum size of 3 acres, similar irradiance and infrastructure standards, and focus on plots that support Agri-PV systems for simultaneous farming and energy production.

Terrain constraints, including slope (must not exceed 8%), are evaluated to ensure economic project viability. Land suitability screening excludes forest buffer zones, wetlands, critical habitats, and areas at risk of floods and soil erosion.

High Potential Districts and Land Distribution

District-level analysis highlights several regions with exceptional potential:

• High-potential districts include Tirupur, Karur, Coimbatore, Erode, Namakkal, and Tiruchirappalli. Each hosts multiple plots of suitable size and proximity to infrastructure.
• For ground-mounted solar: Top districts reported large contiguous unused plots with over 1 GW capacity each.
• For Agri-PV: Prime cropland areas in central and western districts provide scalable dual-use solutions.

These findings are critical for prioritizing action zones and streamlining investment, policy, and infrastructure planning across Tamil Nadu.

Environmental Safeguards and Sustainable Planning

Sustainability is integrated by excluding protected land, critical wildlife areas, and flood-prone zones from potential solar deployment. The ecological assessment rates every parcel for flood risk, soil erosion, and intersection with endangered species’ habitats, ensuring development does not conflict with environmental resilience or conservation goals.

Most plots classified as high technical and development potential score low on environmental sensitivity, confirming the suitability of Tamil Nadu’s land resources for sustainable solar expansion.

Recommendations for Implementation and Policy Support

The pathway forward involves:

• Establish solar zones and clusters based on verified land data
• Promote Agri-PV with standards and incentives for farmers
• Improve grid connectivity and distributed generation
• Designate sensitive zones for conservation
• Align zoning guidelines with local needs and ecological priorities

Integrating solar power with water management, afforestation, and climate adaptation measures will further enhance land utility and overall resilience.

Conclusion: Empowering Tamil Nadu’s Energy Transition

Solar energy potential in Tamil Nadu is vast, with unused and cropland resources providing the foundation for surpassing state energy targets. Through geospatial mapping, strategic planning, and attention to ecological safeguards, Tamil Nadu is positioned to lead India in combining renewable energy growth with sustainable development.