Air pollution is a public health emergency. Besides suspended air particles, sulphur dioxide (SO2) is a major pollutant contributing to deaths from air pollution worldwide. Power plants burning coal and oil along with refineries are responsible for two-thirds of anthropogenic SO2 emissions. With about 90% of power generated in India coming from coal-based plants (comprising about 55% of the country’s installed capacity) and dependence on coal power expected to continue at least for a few more decades, SO2 emission from these power plants is really a matter of great concern. Keeping this in view, the Union Ministry of Environment, Forest and Climate Change (MoEFCC) came out with new environmental norms in December 2015 for reducing emissions from the coal-fired power plants. The measures, among other pollutants/emissions, also include standards for SO2 emission.
The new norms require that SO2 emission from the coal-fired units installed before 31st December 2016 and having less than 500MW capacity is restricted to 600 mg/Nm3. However, for units having 500MW or higher capacity and installed before 31st December 2016, SO2 emission needs to be restricted to 200 mg/Nm3. Further, units installed after 1st January 2017, irrespective of their size, will need to restrict SO2 emission to 100 mg/Nm3. Originally these norms were required to be complied by all coal-fired units by 31st December 2017. Subsequently, the deadline was extended for implementation in a phased manner by December 2022, except for units located in the NCR region which were required to be made compliant by December 2019.
A comparison of SO2 emission norms adopted by some other major emitters and developed/developing countries in the world would leave very little room for any doubt about the urgent need for similar stipulations and enforcement in India as well.
Compliance with the new norms required 448 operating coal-fired units in the country to install Flue Gas Desulfurization (FGD) system. Of these units, 149 fall under Central Sector, 166 under State Sector and the remaining 133 under Private Sector. Considering the deadline for compliance and time required for installing and making the FGD system for each of these units operational, the equipment must have been at least under an advanced stage of supply or erection by now. However, a study of the current state of affairs in this regard shows a grim picture.
As per the recent CEA status report, the work for installing the FGD system has so far been awarded only for 155 units; and 114 out of these 155 units are in the central sector (amounting to 70% of the awarded capacity). The state units and the private sector have not taken up the work at the required pace and in such a scenario the stipulated deadlines for compliance is unlikely to be met. The return on the investment required to comply with emission standards should be attractive to incentivize power plant owners to implement these norms and all additional operating costs should be reimbursed, opine experts in this field.
With about 6MT/year emission of SO2 from coal-fired power plants, Indian power plants are already the biggest SO2 emitters in the world; the other major emitters like China and the USA having already reduced their SO2 emission either by switching to clean source of energy or by adopting stringent emission standards and strict enforcement of the same.
Sulphur dioxide is a major public health hazard not only due to direct exposure to it but also due to exposure to the particulate matter (PM2.5) that is formed when SO2 reacts with other air pollutants. Therefore, limiting its emission is of utmost importance for the wellbeing of the citizens of India. With the socio-economic development and increase in GDP, India’s energy needs are bound to increase over the coming years; and notwithstanding a strong push for solar energy, coal will continue to be the main source of energy.
Compliance of the environmental norms stipulated by the MoEFCC by selective players to reduce sulphur dioxide emission while a majority remains non-compliant, is going to be immensely counterproductive, without yielding the intended results. Again, any effort to control SO2 emission only selectively at identified hotspots also may not be a good strategy as it will still leave the substantial source of SO2 emission unattended. It may lead to the setting up of new installations at places that are not hotspots currently and may lead to the emergence of new hotspots in future. While the ideal situation would be to immediately stop non-compliant power plants, irrespective of location or base emission levels, after deadlines are over, running these plants should be resorted to only under severe power shortage situations with heavy penalties and it should be used only as the last option. The penalties so recovered should be used to provide incentives to compliant power plants so that their increased cost of power production on account of compliance can be offset.