An emissions trading scheme developed in Gujarat is moving from an industrial experiment to an international policy model, with Brazil’s Rio de Janeiro examining whether it can adapt the approach for particulate pollution. For Delhi-NCR, where winter air pollution repeatedly produces restrictions, enforcement disputes and pressure on economic activity, the Gujarat experience raises a larger question: can industrial compliance be designed around incentives and measurable limits instead of inspections and shutdowns alone?
The model began nearly 15 years ago, when economists, engineers and regulators started exploring whether factories could be persuaded to cut pollution without treating every breach as a reason for closure. The approach was eventually piloted in Surat in 2019 by researchers affiliated with the Energy Policy Institute at the University of Chicago and J-PAL, working with the Gujarat Pollution Control Board.
Its central idea is to place a cap on pollution from an industrial cluster and divide that cap into permits. A factory that cuts emissions beyond its target can sell its surplus permits to another plant that finds pollution reduction more difficult or expensive. This creates a market for compliance while keeping total pollution within the overall limit set by regulators.
The arrangement differs from the conventional system described in the report, in which regulators largely depend on periodic inspections, emission limits, penalties and shutdown notices. Under an emissions trading scheme, factories continue to face an overall environmental constraint, but they receive greater flexibility in deciding how to meet it. The intended result is that pollution reduction occurs where it can be achieved most efficiently.
The Surat pilot provided an unusual basis for comparison. It covered 162 of Gujarat’s 317 large coal-burning industrial plants, while the remaining plants continued under conventional regulation. This allowed researchers to compare plants participating in the scheme with those outside it rather than relying only on before-and-after changes within the same group.
The participating plants cut particulate emissions by 20% to 30% and reduced pollution-control costs by 11%, according to the findings reported by Times of India. Compliance reached 99%, compared with roughly two-thirds under conventional regulation. Researchers estimated that the benefits exceeded the costs by at least 25 times.
The reported emissions data gives the results a more concrete scale. A typical plant under conventional regulation emitted about 1,300 kg of particulate matter each month. Similar industries operating under the emissions trading scheme reduced emissions to approximately 900 kg to 1,000 kg a month. The reduction continued across all 10 compliance periods during the nearly two-year study, which ran from April 2019 to 2021.
That consistency is significant for urban pollution control because it suggests that the outcome was not limited to a single compliance cycle or an initial response to a new rule. The reported findings indicate that participating factories maintained lower emissions while also spending less on pollution control. The scheme’s flexibility allowed individual firms to choose how to meet their obligations rather than requiring identical responses from plants with different technologies, costs and operating conditions.
The institutional design was also important. The Gujarat Pollution Control Board remained responsible for the regulatory framework, while researchers helped design and evaluate the pilot. The market mechanism did not remove government oversight; it changed the way compliance was organised within a pollution cap. That distinction matters because a trading system depends on regulators setting the cap, measuring emissions, issuing permits and ensuring that reported reductions are credible.
Michael Greenstone, co-chair of the Emissions Market Accelerator and one of the four researchers involved in the experiment, described the model as having been made, tested and demonstrated in India. Dr Kaushik Deb, EMA’s executive director, said the initial challenge was convincing industrial units that cleaner air did not have to come at the expense of growth. According to Deb, the scheme was designed so that there were no losers, and only one industrial closure occurred under the system in seven years.
The reported expansion suggests that the programme is no longer confined to one industrial cluster. It now covers a population of nearly 300 million across the country and is expanding to sulphur dioxide and wastewater pollution. The source material does not provide a detailed list of the locations covered or explain the precise design of these newer applications, but the expansion indicates an attempt to apply the same incentive-based logic to pollutants beyond particulate matter.
The international interest has added another layer to the experiment. Rio de Janeiro has signed a letter of intent to examine adapting the approach to its pollution challenges. If implemented, Rio would become South America’s first emissions trading system for industrial particulate pollution. The model’s journey from Surat to Rio reflects a policy pathway in which a locally tested instrument gains credibility through measured results before being considered elsewhere.
The scheme’s international visibility increased after Gujarat became an Earthshot Prize finalist in 2025. The prize, founded by Prince William, identifies and helps scale environmental solutions. Dr Bala Srinivasan, EMA’s co-chair, said the recognition opened conversations beyond India, including with Rio, while also generating interest among Indian states as the prize prepares to come to Mumbai later this year.
For Delhi-NCR, however, the Gujarat model cannot simply be transplanted. The source report itself notes that the national capital region’s pollution problem is more complex than Surat’s industrial cluster. Delhi-NCR’s air quality is influenced by multiple sectors and sources, while the Surat trial focused on large coal-burning industrial plants. The evidence therefore supports the model as a policy option for industrial emissions, not as a complete solution to the region’s wider air pollution crisis.
This distinction is central to understanding what an emissions trading scheme can and cannot do. A market for permits can organise reductions among participating industrial units, but it does not automatically address pollution from every sector or establish how different sources should be measured against one another. Its effectiveness depends on a clearly defined pollution cap, reliable monitoring, enforceable compliance and a regulator capable of maintaining the integrity of the system.
The Surat results nevertheless challenge a familiar assumption in urban environmental governance: that stronger pollution control must necessarily mean greater economic disruption. The reported trial found lower emissions alongside lower pollution-control costs. It also recorded higher compliance among participating plants than under conventional regulation. These findings suggest that the design of regulation can influence whether businesses experience cleaner production as a penalty, a fixed obligation or a competitive opportunity.
That insight is relevant to Delhi-NCR because repeated restrictions often bring the conflict between environmental protection and economic activity into public view. The Gujarat experience does not resolve that conflict, but it offers evidence that the two objectives do not always have to be treated as opposites. If firms can reduce emissions more efficiently and benefit from surplus permits, pollution reduction may become part of how they compete rather than only a condition imposed after violations.
The larger urban question is whether India’s pollution-control institutions can move from episodic enforcement to continuous, measurable management. The reported trial provides evidence for one model: a regulator defines the environmental boundary, factories receive flexibility within it, and researchers compare outcomes against conventional regulation. Its success depends on the administrative detail behind the market, not on the market label itself.
What the evidence confirms is limited but important. In the Surat pilot, participating plants reduced particulate emissions by 20% to 30%, cut pollution-control costs by 11% and achieved 99% compliance. The model has since expanded across a population of nearly 300 million and attracted interest from Rio de Janeiro. What remains uncertain from the supplied material is how the system would perform across Delhi-NCR’s wider mix of pollution sources and institutions. The next developments to watch are its expansion to sulphur dioxide and wastewater pollution, further adoption by Indian states, and whether Rio moves from examining the model to implementing it.
