Chennai to boost bio-CNG capacity as composting centres near closure

The Greater Chennai Corporation (GCC) is set to expand its network of Bio-CNG plants as part of a shift towards sustainable waste management, following widespread concerns over the functioning of Micro Composting Centres (MCCs) and Material Recovery Facilities (MRFs).

In a status report submitted to the National Green Tribunal’s southern bench, GCC confirmed that several MCCs and MRFs located in burial grounds and residential areas will be shut down due to objections from residents over foul odour and inappropriate siting. As of January 1, 2025, the city was operating 190 MCCs and 137 MRFs across 15 zones, but nearly one-third of them were situated inside burial grounds, triggering strong opposition.

To address the issue, GCC has decided to phase out poorly performing facilities and redirect organic waste to its Bio-CNG plants. Currently, Chennai has two operational plants—at Chetpet (150 tonnes per day capacity) and Madhavaram (160 TPD)—that process wet waste into compressed biogas, a cleaner alternative to fossil fuels. Five additional Bio-CNG facilities are under construction, with the Sholinganallur and Madhavaram (Part II) units expected to start operations within three months.

This transition is expected to not just tackle the problem of odour and unutilized compost piling up at MCCs but also strengthen the city’s push for renewable energy. Bio-CNG produced from wet waste can be used for cooking, transportation, and power generation, offering both environmental and economic benefits.

Last year, the city corporation held that it will build five new bio-CNG plants that will have a capacity of 100 tonnes and will produce 4,000 kg of biogas daily.

The Corporation has also outlined plans for large integrated waste management hubs at Kodungaiyur and Perungudi. These facilities will combine Bio-CNG plants with composting units, automated MRFs, and waste-to-energy systems. Construction has already begun at Kodungaiyur, while Perungudi will soon house a 100-tonne windrow composting plant as part of the city’s long-term strategy.