Delhi NCR Coal Plants Deepen Regional Air Quality Risk
Delhi-NCR’s air pollution challenge is increasingly being shaped beyond the region’s administrative boundaries. A new assessment of coal-fired power plants within a 300-kilometre radius found that most estimated sulphur dioxide (SO₂) emissions came from facilities no longer required to install flue gas desulphurisation (FGD) systems. The findings raise questions about whether pollution-control rules are keeping pace with the regional nature of air pollution and rising electricity demand.
The analysis examined 25 of 37 coal-fired generating units in the wider Delhi-NCR region for which public emissions data was available. These plants were estimated to release around 154 kilotonnes of SO₂ in 2025. Nearly 90% of the emissions came from units without FGD systems, while Category C plants, which are exempt from mandatory FGD installation under the revised framework, accounted for 81% of the estimated total. The concern is not limited to the immediate vicinity of a power station. SO₂ can contribute to the formation of secondary fine particulate matter, including PM2.5, after chemical reactions in the atmosphere. That makes the location-based approach to pollution regulation increasingly significant for a region where air quality is influenced by emissions travelling across state borders. The policy shift followed repeated extensions to the original 2015 requirement that coal-fired plants install FGD technology.
A July 2025 framework exempted a large majority of coal power units from mandatory installation, while retaining stricter requirements for selected categories of plants. The change has since intensified debate over the balance between compliance costs, electricity affordability and public health. For cities, the issue is closely linked to energy planning. Heatwaves and growing cooling demand are increasing pressure on the power system, potentially raising coal generation during periods of peak consumption. Without stronger controls, the expansion of electricity supply could continue to carry significant air-quality costs for communities far from the plants themselves. The assessment also points to a measurable difference between plants with and without effective SO₂ controls.
Its comparison of units with similar generation levels found substantially lower estimated emissions from facilities operating with FGD systems. The broader implication is that cleaner electricity cannot depend only on where a plant is located; the pollution-control technology used at the source also matters. The next challenge is enforcement and transparency. Making real-time emissions data publicly accessible and reassessing exemptions could give regulators, researchers and affected communities a clearer picture of regional pollution. For Delhi-NCR, cleaner air will ultimately depend on treating the power network as a shared environmental system rather than a collection of isolated facilities.
