Subscribe
On July 29, Mahagenco Koradi issued expression of interest inviting manufacturers to bid for installation of flue-gas desulphurisation in its upcoming 660 MW supercritical power station. By August 10, the manufacturers will submit their expression of interest statements. It is to be noted that the thermal power station started running the unit without installation of FGD despite being asked by the Ministry of Environment, Forests and Climate change (MoEF&CC) through its environmental clearance letter. Much to the dismay of environmentalists and media, Maharashtra State Pollution Control Board, which is responsible for monitoring the implementation of MoEF&CC conditions, had given go ahead to the company to begin its commercial operations disregarding the ministry’s orders.
Norms flouted
The plant has been pleading to the ministry to consider relaxations of the very first clearance conditions it had issued to the power station. Through the state energy ministry, the plant had approached Maharashtra chief minister Devendra Fadnavis urging him to get the requirement of installing FGD waived off. Much to people’s shock, the CM agreed and wrote a letter to the then environment minister Prakash Javadekar in this regard on July 8, 2015, according to media reports.
With political support, the plant has been operating with no FGD units in place.
When the pollution control board was asked, V M Motghare, Joint Director—Air Pollution Control, Maharashtra Pollution Control Board said, “We have denied consent to operate for two units in the plant. Four old units have been retired.” However, he avoided much information about the controversy on FGD citing busy schedule.
FGD systems
Koradi power station is located 15-20 km from Nagpur and has two units of 210 MW each, four units of 105 MW each installed before 1990 and one 660 MW unit, which was commissioned in December 2015. Two units of 660 MW each are under development. With the cities in Maharashtra growing by volume and recording considerable levels of sulphur dioxide emissions (about 10 micrograms/cubic meters), it is only precautionary that this power station, which is a potential contributor of over 20-60 (on 1-3 units operation) micrograms/cubic meter in excess into ambient air, was asked to install FGD systems. These are one of the most expensive pollution retrofits in power stations. The 660 MW plant will have to invest about Rs 330 crore, 8-10 per cent of the construction cost of the plant.
Now with the new emissions norms coming into picture and no response from MoEF&CC on relaxing the FGD system, the MAHAGENCO board of directors has finally consented to install FGD system. “The process is in pipeline, we have not come out with any concrete decisions,” said Apale, public relations officer, MAHAGENCO. Question about the FGD controversy raised hackles with Jeddaoo, Chief Engineer, Koradi Power Station.
India second largest emitter of SO2 in the world
The case of MAHAGENCO Koradi reflects the negligent attitude of government officials towards public health who can only look through environmental investments via a cost-benefit microscope discarding threats of cancer and acid rain. It is imperative to note that images released by NASA’s Aura satellite show doubling of sulphur dioxide concentrations over India in 2012 when compared to 2005. Emission inventory estimates published by Zifeng Lu, scientist at Argonne National Laboratory and the US Environmental Protection Agency confirm India as the second largest emitter of SO2 in the world, a significant share of which is produced by coal-based power plants. Though Indian coal is low in sulphur content, its calorific value is also low. Therefore, the power plants use relatively large quantity of coal per unit of electricity generated. As a result, total SO2 emissions by Indian plants are high.
Power plants where FGD is installed
With installation of FGD, MAHAGENCO Koradi will be the second inland freshwater-based FGD installation in India after NTPC Vindhyachal. Only six out of 186 GW coal power plants in India—Tata Power-Trombay (750 MW); Dahanu Thermal Power Station (500 MW); Udupi Thermal Power Station (1200 MW); JSW Ratnagiri (1200 MW); NTPC Vindhyachal stage-V (500 MW) and Adani Power Mundra Ph-III (1980 MW)—have installed FGDs. Two of these installations, Udupi and Dahanu, were by Ducon and the rest were by Alstom. Except NTPC Vindhyachal stage-V, the rest of the plants have seawater-based FGD systems.
With FGD and control of oxides of nitrogen system in place, Mahagenco Koradi would be a state-of-the-art plant to aid training of officials. Koradi was the first power plant in India where ESP-Bag filter hybrid combination was experimented, the old units of the plant were replaced with new supercritical unit and now treated waste water is being used in the plant for ash handling.
With inputs from Koshy Mathew, Research Intern, CSE @ koshydelhi@gmail.com