As part of the BS6 Phase II emission standards, RDE (Real Driving Emission) tests were mandated to reduce the gap between emission tests in the laboratory and the real-world driving emissions of a vehicle. They are undertaken in multiple driving scenarios, ranging from highway, city and rural terrain. During the test, a device named Portable Emission Measurement System (PEMS) is used for accurate (RDE) real world driving emission measurement. This is specifically to monitor and control the emission of carbon monoxide (CO), carbon dioxide (CO2) and oxides of nitrogen.
Emission Regulations Globally
The first emission standards were introduced in 1963 in the US. It was then later adopted by Canada, Japan, Australia and European Union. Currently, several global markets use the US, Japanese and European standards as their base, with EURO standards being the most widely adopted.
In 2023, a new iteration of EURO 6 standards was introduced (EURO 6E) and adopted. Originally, EURO 6 was introduced in 2014 after a European automaker was caught in an emission scandal (Diesel gate).
Real Driving Emission norms were originally a package of EURO 6 in 2017 to deploy a more robust mechanism for the after-treatment of Nitrogen Oxide (NO). It also played a crucial role in making OEMs mass adopt gasoline particulate filters (GFP) in their vehicles. That’s because road transportation is among the biggest contributors to emissions in Europe (20%). China was the first nation to adopt these standards as it is the largest contributor of greenhouse gases globally.
India too is neck-to-neck with global standards for emissions with BS6 Phase II which has exactly similar compliance figures as Euro 6. As of March 2024, the emission standards and compliance for EURO 7 have been forged and are awaiting approval.
Where does India stand?
In India, the transportation sector accounts for 12% of total emissions which is relatively lower than that in Europe (20%). Despite that, on April 1, 2023, BS6 Phase II norms were introduced. This mandated OEMs to integrate multiple emission monitoring and controlling devices. These included selective catalytic converter (SCR) or exhaust gas recirculation technique, OBD, and Diesel particulate filters in diesel vehicles.
The new compliance is not just limited to hardware changes. The more significant change has been the rise in the ethanol content in our fuel in recent times. Earlier, E10 was introduced under a pilot test which was later replaced by E20 in BS6 Phase II.
Also, the higher ethanol content has a different air-fuel ratio, octane value and density. Engines with BS4 compliance will have a hard time using this fuel - neither do they have sensors to monitor combustion and emission which we now have in BS6 vehicles, nor have they had a fuel injection (closed-loop FI) system that was calibrated to burn this fuel.
The Government is targeting a nationwide rollout of E20 by 2025.
As of now, Euro 7 emission compliance is in the approval stage and once it is approved, we may see a new iteration of Bharat emission standards (potentially BS7) being introduced in a similar time frame. Mirroring these standards, even real world emission monitoring (RDE) is not just to curb harmful emissions but also to meet the criteria of a potential export market for vehicles manufactured in India for the “Make in India” initiative.
This will help cut crude oil import and pollution and help with the widespread adoption of alternatives like ethanol blended petrol, flex fuel and hybrid systems. One thing is for sure – the next emission standards will be more stringent but strive for a perfect balance of industrial viability and environmental concerns.
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