Green Schools of Tamil Nadu Cut Power Use in Half: Study

Rooftop solar systems installed under Tamil Nadu’s Green School Scheme have reduced grid electricity use by an average of 46 percent per school, according to a recent impact study released on Monday. The findings highlight how renewable energy and passive cooling measures are helping schools lower costs while creating safer learning environments.

The programme is implemented by the Department of Environment and Climate Change under the Tamil Nadu Climate Change Mission. It is designed to convert school campuses into “living laboratories” that promote climate awareness and sustainable behaviour.

Scale and Implementation

The scheme is currently being implemented in 297 schools across several phases. Support comes from the UNEP Cool Coalition through the Swiss Agency for Development and Cooperation–funded BeCool Project.

The impact study, prepared by the Indian Institute for Human Settlements, reviewed 97 schools covered under Phase 1 and Phase 2 of the programme.

Integrated Sustainability Measures

Green Schools combine multiple sustainability practices. These include rooftop solar panels, rainwater harvesting, drip irrigation, waste segregation, composting, and the development of kitchen, medicinal, and fruit gardens.

While climate education remains the primary goal, the study found that the programme is also producing measurable gains in energy efficiency and resource management.

Reduction in Electricity Consumption

An analysis of electricity bills from 49 schools showed a sharp decline in grid power use after solar systems were installed. Average monthly consumption fell from 607.7 kilowatt hours to 328 kilowatt hours per school.

Annual grid savings were estimated at 3,572 kilowatt hours, equal to around INR 26,000 per school each year. In addition, solar generation contributed nearly 1,350 kilowatt hours annually, valued at about INR 4,700.

At a Government Higher Secondary School in TN Palayam, Erode, bimonthly consumption dropped from 325 units to around 60 units after installation. This represented a reduction of 50 to 60 percent.

Cooling Initiatives and Heat Reduction

Alongside solar installations, the State has launched a Cool Roof programme in selected schools. Pilot projects in Chennai recorded classroom temperature reductions of 3 to 4 degrees and ceiling surface temperature drops of 4 to 5 degrees.

These measures aim to reduce heat stress and improve indoor comfort during periods of extreme heat.

Energy Demand

The report noted that some schools still rely heavily on grid electricity. High loads from borewell pumps and outdated electrical equipment continue to limit savings.

The study recommended that efficiency upgrades should accompany solar adoption to achieve deeper reductions in power use.

Chief Minister MK Stalin said the programme seeks to build heat-resistant learning spaces while promoting climate justice. Balakrishna Pisupati, Country Head of UNEP India, said the initiative helps students learn better by keeping classrooms safe and comfortable. He added that extreme heat affects children more severely and that simple, scalable solutions can make a meaningful difference.

Districts across Tamil Nadu face different levels of heatwave risk. About 13 percent of districts are moderately to highly vulnerable due to urbanisation and the Urban Heat Island Effect.