Thermal plants emission guidelines

Reading time: 8-10 minutes.

Coal-based power plants emit a large range of externalities, which impact the local and regional air qualities, which further have a significant impact on human health. Air pollution occurs when there is a release of harmful particles in large concentrations. Burning coal to produce electricity releases PM10, SO2 (Sulphur Dioxide) NOx (Oxides of Nitrogen) and Hg (Mercury). If the emission trends of thermal power plants remain unchanged, projections estimate that these pollutants are capable of causing an estimated 1.3 million deaths in India per year by 2050

With the primary aim of minimising the effects these four pollutants on air pollution, the Central Government set certain guidelines that were notified by the Ministry of Environment, Forest & Climate Change (MoEFCC) in December, 2015 for coal-based Thermal Power Plants in the country.

The guidelines aim at reducing the emission of PM10, Sulphur Dioxide and Oxides of Nitrogen, thereby, aiming to improve the Ambient Air Quality and also aim at coordinated attempts for conservation of water and make the resources of energy sustainable.

Why was it introduced?

Various studies have suggested that the coal-based power sector has been one of the most critical sectors of the Indian economy. As a result of various studies, including one by the Centre for Science and Environment (CSE), the coal-based power sector was found to be one of the most resource wasteful and polluting sectors in the world. It was also found that our pollution norms were significantly weaker than other major economies, including China, where particulate matter (PM) was five times lesser than that of India.

The study also suggested that almost two-thirds of the plants in India either failed to comply or were unwilling to comply with even the most lenient regulations. As of 2014-15, the power plants used around three-fourths of the coal used in the entire country. India’s coal is of poor quality with almost 40 per cent ash. This means that the use of such coal leads to greater air pollution and is a significant contributor to total pollutants such as PM, NOX and So2 in the country.

Various studies also reported that domestic power plants were inefficient in using fresh water. Their average fresh water consumptions were twice that of the consumption of plants in countries like United States and China. It was estimated, therefore, that is the pattern remain unchanged, the pollution was expected to worsen on multiple levels.

In a Panel Discussion organised by the Centre for Policy Research, it was significantly pointed out that the emissions from Coal Based Power Plants in India contribute to significant air pollution including sulphates, nitrates, mercury and secondary particulate matter, largely formed by SOX emissions. Coal, fly ash and secondary particles from thermal plants and industries in Delhi contribute up to 35 percent of PM2.5 in during Winters and up to 41 percent during Summers.

Since Delhi is in the Indo-Gangetic Belt, the effect of these emissions spreads to areas across Northern Capital Region (NCR), within a radius of 300 kilometres by the north-westerly winds. Research shows that ever since there has been an increase in the particulate matter around Delhi, it has been linked with the presence and growth of coal-based power plants in the region. In addition to this, more than half of the present operational plants are in five states- Maharashtra, Uttar Pradesh, Chhattisgarh, Madhya Pradesh and Gujarat.

Therefore, the central government introduced the revised guidelines in 2015 and these were notified by the Ministry of Environment, Forestry and Climate Change in December 2015. The new standards emphasise on reducing the emissions of these four pollutants but also on bringing an ambient air quality in and around the thermal power plants. The guidelines make reference to the use of technology which should be employed for the control of proposed limit of Sulphur Dioxide and Nitrogen Dioxide and would also help in controlling mercury emissions as a co-benefit. Since these guidelines have at their core, the aim of reducing the use of water in thermal power plants, this will also lead to water conservation as thermal power plant is a water-intensive industry. This is aimed at further reducing the usage of energy for the drawl of water.

Salient features of the guidelines

The Guidelines have several significant features:

  • Categorisation of thermal power plants into three categories

According to these guidelines, Thermal power plants are categorised into 3 categories, namely: Those Plants that are installed before 31st December, 2003, those Plants that are installed between 2004 and 31st December, 2016, and those Plants that are installed after 31st December, 2016, i.e. in and after 2017.

  • The new guidelines make addition to the existing guidelines

While the previsions and/or existing guidelines before 2015 governed on the PM emissions, the new guidelines aim at reduction of emissions for all major pollutants – PM, SO2, NOx and mercury emissions (Hg).

  • Specific regulations for plants installed in and after 2017

Under these regulations, plants installed in and after 2017 are required to meet Particulate Matter emission standards of 30 mg/Nm3, i.e. an 80 per cent reduction over the norms that existed prior to the 2015 norms. These new plants installed in and after 2017 are also required to install pollution-control equipment such as Flue Gas Desulphurization and low NOx burners to meet the standards, while the older plants (i.e. ones established priori to 2017) are required  to meet considerably looser standards, based on their age, due to both economic considerations and technical challenges involved.

  • Regulations in terms of water usage

The guidelines aim to remarkably reduce the withdrawal of freshwater by thermal power plants. This is intended to decrease the cumulative freshwater withdrawal by 80 per cent from around 22 BCM in 2011-12 to around 4.5 BCM in 2016-17. The norms will require all freshwater-based once-through-cooling (OTC) system plants to install water-efficient cooling towers that consume up to four cubic metre per watt hour (m3/MWh). Furthermore, existing cooling tower-based plants are required to restrict water consumption to 3.5 m3/MWh and plants that set up after January 2017 are required to achieve 2.5 m3/MWh as per the guidelines of 2015.

  • Regulations in respect of fly ash

Since the utilisation of fly ash from power plants has been far below the 100 per cent target that was supposed to be achieved by 2014, the government introduced draft amendments in March 2015 to push fly ash use. The proposed notification mandated the construction activities, i.e. buildings, roads and flyovers, reclamation and embankments, within 500 km of power plants to use only fly ash. The power plants were also required to provide fly ash for free to construction agencies and to transport it at their own cost up to 100 km for private users and up to 500 km for government projects.

  • Compulsory upgradation of supercritical technology

In addition to the features mentioned above, as per the action plan on which these guidelines are based, the Ministry of Power announced its plans to mandate supercritical technology for Ultra Mega Power Projects (UMPPS) as well power projects during the 13th Five Year Plan period, however, almost 40 GW of the 87 GW capacity projects under construction are subcritical. Subsequently, the power ministry also announced plans to shut down around 36 GW of old capacity that is inefficient.

Critical analysis

  • Power deficiency and idle power plants

Electricity is central to India’s developmental efforts. However, it is a fact that almost one-fourth of our population lives without access to electricity. Our per capita consumption of electricity is also considerably low, at almost a third of the world average with millions getting power a few hours a day. Surprisingly, the plant load factor (PLF) for power plants has steadily declined over the last two years and was only 63.60 per cent in September 2015. PLF is the ratio between the actual energy generated by the plant to the maximum possible energy that can be generated with the plant working at its rated power capacity for a given duration.

The reason behind the low Plant Load Factor (PLF) could to be the increase in total capacity as compared to the growth in demand. Coal shortages and grid problems are also responsible. But a more fundamental problem is the dysfunctional nature of distribution companies (DISCOMS)—inefficiently run with huge losses, they don’t have the money to buy power and supply it to people. Meanwhile, huge generating capacity lies idle.

This further aggravates the issue of pollution. DISCOMS prefer buying from the older, more polluting power plants because their electricity is cheaper than that generated by the new plants. This happens because the old plants are fully depreciated and, as a result, their input cost is lower. However, in the process, these old industries which supply cheaper electricity continue to produce more which leads to deterioration of the air quality even further, despite there being regulations in place.

  • Lack of emphasis on the functioning of old plants

While the introduction of standards for new plants has been beneficial, the lack of updated guidelines for existing old power plants has led to unrestrained pollution by the old plants, which contribute to the bulk of the environmental impacts. Without stricter regulations with regards to old plants, there will be little incentive to invest in improved technologies because the industries would tend to rely on the activities of older plants because they are cheaper and do not require spending huge amounts of money on the installation of environment-friendly technologies. Therefore, it is suggested that the guidelines be introduced in terms of imposition of stricter regulations for existing plants as well as in order to have a comprehensive implementation of the policy.

  • Failure to impose ambitious timelines

It is worth noting that the power sector has in the past failed to impose its targets in the ambitious timelines. In the last several plan periods, coal-based power capacity expansion was well below the targets.

The new guidelines required installation of cooling towers at numerous plants; SO2 control would require installing flue-gas desulfurization(s) within two years of the issuance of the guidelines, i.e. by December, 2017. Regulators were required to establish clear milestones and ensure close supervision to ensure implementation of these rules. This, given the short deadlines and the huge expenditure on technologies and capital assets that these guidelines maintain has been a problem in the Indian Context and has not been implemented despite attempts by the government in this regard. The primary cause of such a failure is the impracticable deadlines that have been enforced upon the industries and power plants that come under the ambit of the said guidelines.

  • Non-compliance of these guidelines and its impacts

Based on a report by Greenpeace India, based on the data collected from the Central Pollution Control Board (CPCB) via Right to Information (RTI), it is worth noting that India would have reduced 48% of SO2, 48% of NOx and 40% of PM emission respectively if the coal power plants had complied by the Thermal Power Plant emission standards of 2015. Therefore, it is suggested that in order to enhance the accountability and complian the progress for retrofitting the power plants should be made available to the public. The suggested measure would help in maintaining the transparency of actions taken by various authorities with respect to the new timeframe scheduled for the power plants.


The environmental guidelines notified by MoEFCC in December, 2015 are intended to reduce emission of SO2, CO2, particulate matter and mercury from thermal power stations, since thermal power plants are major contributors of these pollutants. Despite deferment of timelines for compliance of the new norms from December, 2017 to (a) December 2022 for all thermal power stations and (b) December, 2019 for the power stations located in NCR, rate at which implementation of emission control systems in the power stations has taken place, is far from satisfactory.

However, since the central government issued the Thermal Power Plants Emission Guidelines in 2015, a number of positive developments have also taken place. These include the following:

First, Central Electricity Regulatory Commission (CERC) Tariff Regulations, 2019 has issued guidelines specifying the modalities for submission of additional capital expenditure on account of revised emission standards, factors to be considered by the Commission for approval of the same and the admitted expenditure on this account forming the basis of tariff determination.

Second, Central Electricity Regulatory Commission has also allowed the cost claimed by the petitioner in the event of the same having been discovered through competitive bidding.

Third, Central Electricity Regulatory Commission regulations also provide for consideration of additional capitalisation and additional operation and maintenance expenses on account of implementation of revised emission standards in existing or new generating stations in their tariff.

Lastly, Central Pollution Control Board has been strictly monitoring the air pollution status of 102 most polluted cities in India. In this regard, the National Green Tribunal (NGT) has given power to Central Pollution Control Board (CPCB) to impose penalties on industries not complying with the norms. CPCB has already issued notice, to all the thermal power stations in NCR.

It is therefore submitted that Plants that do implement the pollution-control technology need to be monitored to ensure that standards are being met. Although, the installation of pollution-control technologies is key in ensuring health benefits due to better air quality, there is a need for the Government to address the financial burden of pollution-control technologies (PCTs) on end-consumers.

The Government can provide subsidies and incentives to Thermal Power Plants so that they are encouraged to follow these guidelines and the objectives of these guidelines can be more successfully met. In addition to this, there is need for the government to introduce measures to make the role of different stakeholders more transparent and accountable measures in order to implement these guidelines.

Author: Priyanshu Grover from Symbiosis Law School, NOIDA, Uttar Pradesh.

Editor: Tamanna Gupta from RGNUL, Patiala.