DT Explains: What is a waste incinerator plant, why are Kodungaiyur residents opposing it?

CHENNAI: In Chennai, where segregation at source has not been successful, managing solid waste has become a burning issue. The Greater Chennai Corporation, which appears to be at its wits’ end, wants to adopt a ‘if we can’t solve the burning issue, let’s burn the issue’ approach. But at what cost?

With the civic body planning to construct a waste-to-energy (WTE) incinerator plant in Kodungaiyur, various civil society organisations, environmentalists, and residents are up in arms. What are their concerns? The basic operation of an incinerator is quite simple: The WTE plant burns non-recyclable garbage, including wet waste, in a combustion chamber.

The heat produced during the burning process converts water into steam, which turns the blades of the turbine generators to produce electricity. However, the end result of the process is not as simple, rather it’s toxic and quite complex.

Burning the waste creates byproducts like pollution-causing gases and ash, which would ultimately go into landfills. Burning also releases sulphur oxides (SOx), nitrogen oxides (NOx), and a particularly harmful ‘persistent organic pollutant’ called dioxins that are known to cause cancer, liver conditions, developmental problems in breastfed infants, and more. It also lets out another pollutant called furan that poses a range of risks to reproductive health and causes neurotoxicity.

Also in the noxious mix are pollutants like hydrochloric acid, heavy metals, and PM 2.5 and PM 10. This scenario goes on to show that the emissions from WTE plants per unit far exceed those from conventional coal-based power plants.

To add some perspective, Delhi, one of the most polluted cities in the world, burns 7,250 tonnes of unsegregated waste every day, releasing gaseous pollutants equivalent to emissions from 30 lakh cars. Even though the volume of trash being burnt in Chennai is nowhere near the national capital’s figures, we are getting there— one tonne at a time.

At present, the state capital has five waste-to-energy incineration plants with a burning capacity of 11.50 tonnes per day. Two plants are under construction, and yet another one has been proposed in Kodungaiyur. To argue that incinerators are useful because they turn ‘worthless’ garbage into cheap electricity is flawed. Electricity and heat generated by burning garbage are neither green nor cost-effective.

Experts say the cost of power generation from waste-to-energy plants, estimated at Rs 7 per unit, makes them an expensive energy source. To further understand the effects of having a waste incineration plant, say, right in your neighbourhood, visit the residents who live around the incineration plant in north Chennai’s Manali, whose houses and vehicles are covered by the toxic ash that escapes from the plant every day.