India’s reservoirs can host 102 GW of floating solar, says first national assessment

Floating solar photovoltaic (FSPV) technology offers significant environmental advantages by utilizing existing water bodies, thereby reducing the pressure on land resources, which is critical for a densely populated country like India. Ground-mounted solar requires large tracts of land, often leading to conflicts with agriculture, forestry, or local communities. FSPV systems are considered land-neutral, avoiding these conflicts. Furthermore, placing panels on water bodies like reservoirs can reduce water evaporation, conserving water resources, which is a significant co-benefit in water-stressed regions. The cooling effect of water on the solar panels also improves their operational efficiency compared to ground-mounted systems, which suffer efficiency losses at higher temperatures. However, the environmental impact on aquatic ecosystems, such as reduced sunlight penetration affecting primary productivity (algae growth) and potential leaching of materials, needs careful assessment and long-term monitoring, as highlighted by the Ministry of New and Renewable Energy.

While the potential of 102 GW is vast, the economic viability of floating solar projects presents a mixed picture. The National Institute of Solar Energy report indicates a significant upfront cost premium; FSPV plants typically cost about 25% more than ground-mounted systems due to the need for specialized floats, robust anchoring systems to withstand water currents and wind, and specialized waterproofing for electrical components. However, this higher capital expenditure (CAPEX) must be weighed against the avoided costs of land acquisition, which in India is notoriously expensive, time-consuming, and fraught with legal complexities. Additionally, the improved efficiency of panels over water can lead to higher electricity generation, potentially improving the Levelized Cost of Energy (LCOE) over the project's lifetime. The government's push, evident in discussions by the Finance Ministry to promote this sector, indicates a strategic shift towards incentivizing these 'land-neutral' technologies to meet ambitious renewable energy targets.

The geographical distribution of India's floating solar potential is heavily skewed towards states with large reservoir capacities. The National Institute of Solar Energy assessment used rigorous geospatial filtering, identifying 1,946 sq. km. of feasible area, primarily in states like Maharashtra, Madhya Pradesh, Karnataka, Odisha, and Telangana. This distribution aligns with major river basins and large-scale dam projects built for irrigation and hydropower. For instance, the Omkareshwar floating solar park on the Narmada river in Madhya Pradesh is a flagship project. This geographical concentration implies that state-level policies and grid integration capabilities in these specific states will be crucial for realizing the national potential. The stringent criteria for site selection—requiring water depth between 3-30m, presence of water for 11 months, and proximity to infrastructure—ensure that only optimal sites are considered, minimizing operational risks but also highlighting the geographical constraints of the technology.