Use of treated sewage instead of fresh water in coal power plants not feasible: report
New Delhi: Use of treated sewage instead of fresh water in coal power plants, as mandated by the central government, is not feasible as about 87% of coal-fired power plants of nearly 200 gigawatt (GW) capacity have no access to treated sewage water, said a new report released by Greenpeace India on Tuesday.
The report also said those power plants that are able to use treated sewage could see a 300-600% increase in water costs, apart from hundreds of crores in capital investments for treatment facilities. Ultimately, the costs will be included in the tariff, increasing the burden on distribution companies and consumers, it said.
Coal power plants require large volumes of water. For instance, a 1,000 megawatt (MW) coal power plant requires about 84 million litres of water each day, assuming that it’s operated at full capacity.
In 2016, water shortages for coal power generation had become acute and due to that, several plants were reportedly shut down for many months. To address such issues, the Indian government, in its revised electricity tariff policy in January 2016, had mandated use of treated sewage water instead of fresh water in coal power plants within 50 kilometers of a sewage treatment facility.
But Greenpeace India, in its report ‘Pipe Dreams,’ highlights that less than 8% of India’s coal power plants can completely switch from fresh water to treated sewage water and only 5% can partially meet their water requirements from treated sewage.
“About 87% or 200 GW of coal power plants would not be able to utilise treated sewage. Over 50 GW of the coal plants currently under construction would not be able to utilise any sewage for cooling,” the analysis added.
The study noted that less than 11% of the total sewage treatment capacity can be utilised by coal power plants.
One of the main difficulties in using treated sewage is that sewage treatment facilities are mostly in metros, far away from power plants.
“For example, Chhattisgarh, Odisha and Madhya Pradesh together account for 77 GW of coal power but can supply treated sewage water sufficient for just 1.5 GW of coal power,” the study said.
The study also said that treated sewage is important for downstream water flows.
“To claim that the use of sewage would solve coal power’s water problem would be like claiming a drop of water will save a man dying of thirst. A more effective solution to the water conflict would be to phase out old, inefficient power plants which tend to consume the most water and emit the most pollutants, while also halting permits for new coal power plants,” said Jai Krishna, who is a Greenpeace researcher and author of the report.