India’s drive towards achieving its updated Nationally Determined Contributions (NDCs), particularly the ambitious target of net-zero emissions by 2070, hinges significantly on expanding solar power capacity. In 2014, the Ministry of New and Renewable Energy (MNRE) estimated India’s solar potential at 748 GW, assuming the use of just 3% of the country’s wastelands. However, given the evolving energy demand and new technological applications, The Energy and Resources Institute (TERI) reassessed this estimate through a comprehensive macro-level study.

TERI’s reassessment identifies eight major categories contributing to the revised solar potential estimate of approximately 10,830 GW. The categories include ground-mounted PV on barren lands, floating solar PV, rooftop solar in rural and urban areas, Agri-PV (including tea and coffee plantations), rail and road integrated PV, Building Integrated Photovoltaics (BIPV), and urban PV. This new potential, based on a combination of literature review, GIS mapping, and realistic assumptions, provides a more robust and forward-looking view of India’s solar landscape.

Ground-mounted solar PV on barren and unculturable land alone accounts for an estimated 4,909 GW. This estimate is based on high-resolution GIS mapping, slope analysis, and exclusion of ecologically sensitive zones, with a conservative assumption that only 50% of the available land would be used to preserve local ecosystems and livelihoods. Major contributors to this potential include Rajasthan (1,234 GW), Madhya Pradesh (731 GW), and Maharashtra (607 GW).

Floating Solar PV (FSPV) offers an additional 100 GW potential, calculated using a 2.5% surface coverage norm applied to selected categories of man-made inland and coastal water bodies. This method was validated through feasibility studies at sites like Bhakra and Pong dams. The highest contributions come from inland reservoirs, tanks, and aquaculture zones.

Rural and urban rooftop PV together contribute another 960 GW, with rural areas accounting for 600 GW and urban areas for 360 GW. This estimate considers per capita roof area, household size, and shading factors. Only pucca and semi-pucca structures are included in the calculation to ensure feasible installations.

Agri-PV presents a massive opportunity, particularly for horticulture, tea, and coffee plantations. With appropriate assumptions and crop suitability indices, this category contributes 4,177 GW. However, the study highlights the need for further pilot projects and R&D to refine the realizable potential and adapt solar layouts to diverse agro-climatic conditions.

The remaining solar potential of 684 GW comes from rail and road-integrated PV (154 GW), BIPV (309 GW), and urban PV (221 GW), with figures largely derived from earlier studies conducted by GIZ. These applications, though less explored in India, offer significant promise in space-constrained environments and for infrastructural synergy.

The study concludes that this revised macro-level assessment significantly expands the solar opportunity for India, aligning with its energy transition goals. It recommends prioritizing micro-level assessments using GIS, satellite imaging, and on-ground validation to refine these estimates into deployable targets. Further, the integration of these diverse PV applications will enhance land-use efficiency, boost rural economies, and make substantial progress toward the country’s net-zero goal.