Bharat Stage VI emission standards: Mission NOT impossible

Back in September 2016, there was much excitement when the Government of India announced a leapfrog to Bharat Stage (BS) VI emission standards. At the same time, it was clear that it would take much hard work to realize the goal and meet the ambitious April 1, 2020 deadline. India is the first to leapfrog from Euro IV-equivalent emission standards directly to Euro VI-equivalent standards, and there were many doubts and questions: Could refineries produce enough ultralow-sulfur fuel, which is necessary for BS VI vehicles, to supply the entire country? Could Indian automakers make their vehicles BS VI compliant by April 1, 2020? Would consumers be willing to pay for the more expensive BS VI vehicles? 

Some considered the leapfrog in fewer than four years to be mission impossible. However, India turned the challenge into an opportunity and completed its mission of producing BS VI-compliant fuel and vehicles on time, Coronavirus notwithstanding. As the country was in lockdown on April 1, 2020, when the BS VI standards went into effect, some might have missed the significance of this major leap forward. What helped bring about this victory?

For one, the necessary ultralow-sulfur fuel is available. One of the crucial features of BS VI fuel is its limit of 10 parts per million (ppm) sulfur content. This is recommended for the operation of modern aftertreatment technologies such as diesel particulate filters, gasoline particulate filters, and selective catalytic reduction systems that are required to meet BS VI emission limits. The National Capital Territory (NCT) started to receive 10 ppm sulfur fuel as early as April 2018. Additionally, several cities in the National Capital Region (NCR) started to switch to 10 ppm fuel at the beginning of 2019, and by October, the entire NCR was supplied with BS VI fuel. According to the chairman of Indian Oil Corp, the firm that supplies roughly half of India’s fuel, almost all refineries in the country started producing the ultralow-sulfur fuel by the end of 2019, to ensure the fuel needed for BS VI was on the market as scheduled. Indeed, ICCT’s recent sampling work found that several cities outside of the NCR had also started to receive 10 ppm sulfur fuels by the end of 2019. 

The Indian auto industry has proved its ingenuity, as well. Tata and Mahindra & Mahindra rolled out BS VI-certified models three to four months before April 1, and Maruti Suzuki launched its first BS VI-compliant gasoline vehicle in April 2019, a whole year prior to the deadline. By January 2020, the company had sold more than 500,000 BS VI vehicles. Not only that, but the domestic brands completed BS VI research and development work mostly in-house

Manufacturers of two- and three-wheelers made similar progress. Ahead of April 2020, Bajaj Auto launched 14 BS VI-compliant three-wheelers and Honda launched three scooters and two motorcycles that are BS VI compliant. The auto industry also ramped down production of BS IV vehicles before the deadline, knowing those vehicles would be mere scrap by April 2020. (However, due to the Coronavirus, the sale of BS IV vehicles will be allowed for 10 days after the current lockdown is lifted.)

As a result of BS VI standards, India’s vehicle manufacturers are moving away from small diesel cars, which have become less attractive to consumers. This is because BS VI diesel vehicles are costlier, require more maintenance, and the government removed its subsidy on diesel fuel. The impacts of these changes on the value proposition for diesels is particularly evident for those with smaller engines, because gasoline vehicles are an attractive and cost-effective alternative. Although sales of small diesel cars are expected to drop, as announced by Toyota, Tata, and Maruti Suzuki, the diesel share of large cars might still increase because larger cars like multi-purpose and sport utility vehicles remain popular and the diesel engine dominates this segment.

The successful start of BS VI is cause for celebration for sure, but it is not the end of the road. Because about half of India’s vehicular emissions today come from vehicles more than 10 years old, the near-term benefits of BS VI standards can be increased dramatically by scrapping older vehicles, especially commercial vehicles. Moreover, the rapid expansion of the vehicle market that’s expected in the coming decades means that BS VI standards can slow down the rate of emissions increase, but cannot stop the trend in the long term. The expected growth in particulate matter (PM) emissions to 2035 is illustrated in the figure below, and this means additional reduction measures are required. These could include, but are not limited to, accelerating the retirement of BS III and IV vehicles after 2025 and looking for emission reductions beyond BS VI.

Figure 1: PM emissions by vehicle age. The years represent the calendar year that vehicles were sold.
Figure 1: PM emissions by vehicle age. The years represent the calendar year that vehicles were sold.

ICCT previously found that a scrappage program combined with BS VI standards could achieve short-term emissions reductions from retiring vehicles and ensure that the long-term emissions reduction potential of the standards is also achieved. Accelerating finalization of the long-awaited scrappage program would help India take full advantage of the efforts that went into achieving BS VI standards and promote the maximum benefits for air quality and public health.

Closing some of the gaps between BS VI and the final Euro 6/VI standards could generate additional reductions. BS VI doesn’t yet fully adopt the Worldwide harmonized Light-duty vehicles Test Procedure (WLTP). Also absent are the Worldwide harmonized Light-duty vehicles Test Cycle (WLTC), on-board fuel consumption meters, and full harmonization of the real-driving emissions (RDE) proposal with Euro 6d, Euro VI D, and Euro VI E provisions (the latter are increased share of urban driving, cold start, and particulate number testing during in-service conformity, respectively). Adoption of these requirements is important for ensuring that the in-use emissions performance of BS VI diesel vehicles in India matches type approval. 

For fleet emissions monitoring, the identification of individual high-emitting vehicles, and the screening for groups of high-emitting vehicles, remote sensing is potentially the best option. The tool is widely used in a number of countries around the world. In particular, China and the United States are demonstrating how remote sensing can contribute to the identification of and enforcement against high-emitting vehicles. Further, the recent real-world emission measurement in London again proved the effectiveness of the tool in identifying high-emitting vehicles. 

There are also efforts underway to develop policies that go beyond Euro 6/VI. These include U.S. Tier 3, Euro 7/VII, and the California heavy-duty vehicle low NOx standards. Here there is an opportunity for India to participate and even lead. Considering the expected future growth in its vehicle market, India needs to continue to build on BS VI and the progress made in reducing tailpipe emissions.

All in all, what seemed like mission impossible fewer than five years ago has been accomplished. The job of reducing air pollution from the transport sector is not done, though, and today there’s doubt about the potential for vehicle electrification that resembles the prior doubts about BS VI. But now that we’ve seen what a determined push can achieve, it would be a mistake for India to aim low on electric vehicles. Instead, India’s mission, should it choose to accept it, is to build upon the momentum of BS VI and aim higher!

Emissions control