What are the benefits of BS-VI as compared to BS-IV?
In India, the Government has set emission standards that regulate the air pollutant directly related to the engine combustion. Since the year 2000, the Bharat stage (BS) values apply for vehicles on Indian roads and the values are set by the Central pollution control board based on European standards.
Currently, we have the BS-IV grade fuel in most states. It is important to note that, by 2020 India is directly moving from BS IV to BS VI (SKIPPING BS-V STANDARD), this has to be borne in mind to avoid confusion.
In simple terms, BS VI fuel is better and pollutants (CO-Carbon monoxide, HC-hydrocarbons, Nox- nitrogen oxides0 from diesel BS VI grade is much more environmentally friendly. Hence the Ministry of surface transport has decided on BS VI. Currently, Euro 6 norms are the best of European standards, BS VI is much closer to these Euro 6 than BS IV.
If there are benefits of supplying BS-VI in petrol pumps, then should it not be supplied to other states as well?
It would be done by 2020, it would be a gradual shift given the millions of vehicles in India.
There are major logistical issues with the change from BS IV to BS VI, the fuel injectors, upgrading the refineries (needs around 50,000 crores), increase in the cost of fuel and vehicles etc. These logistical difficulties and the pressure from SC to implement the change earlier and Delhi being the worst polluted metro would be the likely reasons