TN's sorry solar power scene: Potential one trillion watt hours, installed less than 1%
Of the total DER potential, 60,479 MW is from rooftop solar (RTS) installations alone. But as of April 2025, Tamil Nadu has installed just 1,003 MW of RTS capacity, achieving only 1.66 per cent of its rooftop potential and falling well short of earlier policy targets.
Solar Power System
CHENNAI: Tamil Nadu has the potential to generate up to 1.29 lakh megawatts (MW) of electricity through distributed solar energy systems, enough to meet almost all of its future electricity demand, according to a new report by Auroville Consulting.
If fully harnessed, these solar distributed energy resources (DER) can produce 203 terawatt-hours (TWh) or one trillion watt hours of electricity annually, the study estimated. This would be sufficient to meet 100 per cent of Tamil Nadu’s projected power demand for 2030-31, and 82 per cent of the requirement for 2034-35. However, only 0.78 per cent of this potential has been tapped so far.
Of the total DER potential, 60,479 MW is from rooftop solar (RTS) installations alone. But as of April 2025, Tamil Nadu has installed just 1,003 MW of RTS capacity, achieving only 1.66 per cent of its rooftop potential and falling well short of earlier policy targets.
Electricity demand in the State is projected to rise from 129.73 TWh in 2024-25 to 249.58 TWh in 2034-35, driven by population growth and rising consumption. The report suggests that distributed solar systems could help bridge this demand sustainably while also cutting carbon emissions and reducing reliance on coal and other fossil fuels.
Even if the entire planned solar capacity addition of 18,400 MW by 2034-35 is routed through DER systems, it would only cover 14% of the total solar DER potential. Most of the other distributed applications like floating solar, canal-top, and rail-integrated photovoltaics remain entirely unutilised.
The study, authored by renewable energy expert Rahul Patel and reviewed by Frano D'Silva, Martin Scherfler, and Santhosh Velu, has called for urgent and strategic policy interventions to unlock the State's distributed solar potential. It recommends that the government move beyond rooftop installations and actively promote other DER technologies such as floating solar, canal-top photovoltaics, rail and road-integrated systems, and building-integrated photovoltaics.
Currently, none of these have seen any deployment in Tamil Nadu despite a combined estimated potential of over 68,000 MW.
The authors also urged targeted district-level strategies, streamlined approvals, and incentives for residential, commercial, and institutional consumers to adopt solar technologies. Districts like Tirupur, Kancheepuram, and Tiruvallur have among the highest DER potential in the State but lack focused deployment plans, it added.
