The government of India has announced the adoption of WLTP Cycle (Worldwide Harmonized Light-duty Vehicles Test Procedure) for Bharat Stage VI (BS-VI) emissions testing. The change will take effect on April 1, 2027.
This new testing procedure will be applicable to M1 and M2 category vehicles, including passenger cars, SUVs, multipurpose vehicles, commercial passenger buses, and vans with a gross vehicle weight of less than five tons.
The WLTP cycle is a more realistic way of testing vehicle emissions when compared to the older methods. The European Union had adopted it in 2018. The method ensures that measurements of emissions like carbon dioxide, nitrogen oxides and particulate matter from vehicles are in line with the findings which are done in the laboratory. Currently, the speed-distance-time method for testing fuel efficiency and emission norms in India is the Modified Indian Driving Cycle or MIDC in short.
With the new mandate in place, vehicles manufactured on or after April 1, 2027, must conform to the new WLTP testing cycle to measure emissions. The emission tests under WLTP will be done on chassis dynamometers as per the process in AIS-175 and will be amended from time to time.
In April 2020, India implemented the BS-VI norms for automobiles sold in the country. The shift to WLTP testing cycle will make emission testing closer to the actual on-road driving conditions while keeping the BS-VI emission limits in place.
