Chennai’s Cooling Comfort Comes at a Steep Climate Cost

Chennai’s rising heat and humidity have made it India’s top city for air-conditioner (AC) use, but the comfort comes with a heavy climate burden. A new iFOREST survey finds Chennai households use ACs for an average 4.4 hours daily, the highest among seven major cities. Nearly 87% of households own at least one unit, with penetration expected to rise alongside incomes and worsening urban heat.

Hidden Climate Risks from Poor Servicing

Behind the relief lies a troubling trend: over 50% of households report annual refrigerant “top-ups,” compared with a national average of 41%. Ideally, an AC needs refilling only once in five years. Frequent top-ups indicate leak-prone servicing practices where technicians refill gas instead of fixing leaks, causing continuous greenhouse gas (GHG) emissions.

Most Chennai units use HFC-32 refrigerant, which has 675 times the warming potential of CO₂. On average, households spend ₹2,300 per service — the highest in India — while 64% remain unaware of low-emission refrigerant alternatives.

Scale of the Problem

City-wide, refrigerant leakage caused an estimated 52 million tonnes of CO₂-equivalent emissions in 2024, a figure projected to hit 84 million tonnes by 2035 if current trends continue. A 2025 IIT Delhi study confirms that improper servicing not only raises emissions but also inflates electricity bills for consumers.

What Needs to Change

Experts call for strict enforcement of repair protocols, rapid training of AC technicians, and consumer awareness campaigns. Yet only 16% of Chennai residents surveyed showed willingness to adopt climate-friendlier refrigerants — the lowest among surveyed cities.

While ACs remain essential for heat protection, without better standards and aggressive refrigerant management, Chennai risks spiraling into a “cooling paradox” — where comfort today drives climate crises tomorrow.

Solutions: technician upskilling, affordable low-GWP refrigerants, and informed consumer choices.