As of September 2026, Tamil Nadu had an installed rooftop solar capacity of 1.64 Gigawatt (GW), the seventh-highest among Indian states, compared to 8.53 GW in Gujarat and 5.98 GW in Maharashtra, the two leading states by installed capacity. However, on a per capita basis, Tamil Nadu ranks 14th, with an average installed capacity of just 21 Watts(W) per person, compared with 114 W per person in Gujarat and 63 W per person in Kerala. Tamil Nadu has an estimated technical rooftop solar potential of 60.47 GW. A newly launched state-level capital subsidy, alongside the central government’s PM-Surya Ghar scheme, offers an opportunity to accelerate adoption. While subsidy and financial aid can support adoption across various segments, policy must be clear and easy to follow.
Policy and implementation mismatch
Three policy issues deserve attention. First, building regulations and subsidy eligibility need better alignment. Tamil Nadu’s Combined Development and Building Rules, 2019 (TNCDBR), require rooftop solar installations for specified categories of buildings, with compliance linked to obtaining the relevant completion certification and electricity connection. However, under the PM-Surya Ghar scheme, subsidy support for common facilities in apartment buildings requires an eligible Resident Welfare Association (RWA) to apply. This creates a mismatch in the implementation sequence. Developers may need to install rooftop solar to secure electricity connections, while residents may need to establish an RWA to apply for the subsidy. But an RWA will be formed only after completion of the building and when residents move in.
Punished with network charges
Second, network charges and tariff arrangements for rooftop solar require review. Network charges apply to all rooftop solar energy generation, weakening incentives for self-generation. The aim should be to encourage efficient local generation and not to punish it. The network charges on solar would equate to a tax levied on the farmer for every kilogram of food produced, whether self-consumed or distributed.
Third, consumers without suitable roofs need alternatives. Apartment residents, tenants and households without the right to use their roofs cannot always install individual systems. Community solar and virtual net metering could allow eligible consumers to own a share of a solar installation elsewhere and receive the corresponding benefits through an appropriate billing arrangement. Addressing these barriers would widen participation and make rooftop solar accessible across different housing models.
The central grid will remain essential to Tamil Nadu’s electricity system. But a more geographically distributed and intelligently managed portfolio of solar and storage can complement it. This will not only improve resilience but also create new opportunities for households and businesses. The opportunity is to move beyond treating rooftop solar solely as a climate intervention but recognise it as an investment in Tamil Nadu’s economic competitiveness, energy security and resilience.
The author is the Co-founder and Executive Director, Auroville Consulting.
