Go-green plan mooted for thirsty thermal power units

Power ministry says use of treated sewage water for thermal plants

The country has seen an increase in the number of coal-based thermal power plants — one of the most environmentally damaging forms of power generation. In addition to the fly ash problem, these power plants also require large amounts of water, a scarce commodity in India.

The Central government has estimated that thermal power plants generate about 950 billion units annually, which requires about 2800 million cubic metres (around 7700 MLD) of water.

To generate one unit power, three litres of water are required. The power ministry has estimated that the requirement of water is likely to grow to 12000 MLD by the year 2026-27.

Recently, the Telangana State government has allotted 6.5 TMC of water from the Krishna River every year for the 4000 MW Yadadri thermal power station proposed to be set up at Damaracherla in Nalgonda district. At the same time, for the 4000 MW power plant of the National Thermal Power Corporation (NTPC) at Ramagundam, the government has allotted 60 cusecs of water.

The Union power ministry has advised all states to promote use of treated sewage water for thermal plants.

But many more sewage treatment plants will have to be built if the water requirement is to come from this source. The Central Pollution Control Board data shows that of the 62,000 MLD of sewage generated in the country, just 23,277 MLD is being treated at present. With the high rate of urbanisation, and schemes launched by the Centre, the sewage treatment capacity will have to grow further.

Wherever power plants are situated within a radius of 50 km from a sewage treatment plant (STP), use of recycled water should be made mandatory, the power ministry says.It has suggested that Power plants could work with any investment for STP municipalities for using treated water is included in the sewage water based on either tariff policy and this Public Private Partnership (PPP) cost shall be factored model or Engineering into fixed costs so as Procurement Construction (EPC) not to disturb the merit model with full investment made order of the thermal by the utility or the municipality plant. alone, or both.