Air pollution in Delhi has reached such appalling levels that even the Supreme Court has had to step in and suggest ways to make the air cleaner. Earlier this month, it banned the registration of diesel SUVs and high-end vehicles with engine capacity of over 2000cc in the city till March 2016 to curb emissions. That the move is well-intentioned is undeniable, even if there’s still no clarity on what contributes the most to Delhi’s noxious air. But the big question is: will it work?
Among all the cars sold in India in the last financial year, 37% had diesel engines, a share that has been rising steadily. Moreover, around 90% of the sport utility vehicles and high-end cars sold in the country run on cheaper diesel than on the more expensive petrol. While buyers choose economy, experts say their choice is hurting the environment.
Diesel vehicles are estimated to emit more pollutants than their petrol variants. Analyses of the smoke sent out by diesel vehicles show that it contains worrying levels of ultra-fine particulate matter which can travel deep into the respiratory system, causing ailments such as emphysema and cancer.
The Centre of Science and Environment in Delhi, for instance, says that diesel cars emit three times more nitrogen oxide and 7.5 times more particulate matter than the petrol versions. These pollutants are more dangerous to health than carbon dioxide, which diesel cars arguably emit less.
Costs and benefits
The preference for diesel cars, experts assert, is setting off a process of “dieselisation”, leading to grave health hazards. “More driving results in more fuel use; more toxic pollution per km; more warming per litre of carbon-rich diesel burnt; and, more warming due to its heat-absorbing black carbon emissions,” says CSE in a report on diesel pricing.
In its order this month, the Supreme Court put public good above everything else.
“It is noteworthy that diesel vehicles of 2000 cc and above and SUVs are generally used by more affluent sections of our society and because of the higher engine capacity, they are more prone to cause higher levels of pollution,” a bench headed by Chief Justice TS Thakur said. “A ban on registration of such vehicles will not, therefore, affect the common man or the average citizen in the city of Delhi.”
The order also cracked down on diesel-run trucks and commercial vehicles. “No goods vehicle which is not bound for Delhi will be allowed to enter” the capital from the entry points on the two national highways, it said. Any truck that does pass through Delhi will have to pay double the “green tax”.
The decision was in keeping with the green push of the Delhi government, of the National Green Tribunal, and of the Delhi High Court, which had barred app-based taxi services such as Ola and Uber from running diesel cars in the capital.
Diesel vs Petrol
These moves are welcomed by environmentalists. But they add that there is a need to address a deeper problem: India’s relaxed emission standards.
“As per the standards, a diesel car is legally allowed to be at least six times as polluting as a petrol vehicle in India,” said Vivek Chattopadhyay, a researcher working on air quality and pollution at CSE. “Petrol vehicles, hence, are cleaner than diesel ones, which is odd since the playing field is legally not level and there’s nothing that the government is doing about it.”
Chattopadhyay explains that the latest generations of diesel engines emit less poisonous smoke than, say, those manufactured a decade ago. However, Indians hardly benefit from these advances since lax Indian emission standards allows manufacturers to continue producing polluting vehicles.
India’s emissions norms generally lag behind European standards for diesel and petrol vehicles. At present, about 14 cities in India follow Euro IV standards, which are nine years behind the more stringent norms currently in place in Europe. The contrast is even starker in the rest of the country, which by following Euro III norms is 14 years behind Europe.
“Euro III diesel cars emit 7.5 times more toxic particulate matter (PM) than comparable petrol cars,” CSE says in its report based on data made available by Pune’s Automotive Research Association of India. “This means that one diesel car is equal to adding 7.5 petrol cars to the car fleet in terms of PM emissions and three petrol cars in terms of NOx emissions.”
“This clearly reflects the flawed and lax emissions standards that allow diesel cars to emit more NOx and PM compared to petrol cars,” says CSE. “Total air toxics from a diesel car that are very harmful and carcinogenic are seven times higher than petrol cars.”
Experts say that carmakers have been allowed to get away with manufacturing highly polluting cars because of India’s slow adoption of European standards. As a solution, many of them suggest skipping Euro IV in some cities and implementing Euro V or Euro VI standards directly to curb pollution.
A 2011 study by the Indian Institute of Technology-Delhi, for instance, says the only way to limit PM 2.5 levels in Delhi’s air despite the five-fold rise in its vehicular population is to implement Euro V standards at the earliest. However, the government’s target date for the adoption of this standard is 2020. And Euro VI standards are expected to be implemented in India only in 2024.
At a time when 80 people are dying of poisonous air every day and hundreds are falling sick, waiting a decade for cleaner emission standards may be a bit too late.
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Among all the cars sold in India in the last financial year, 37% had diesel engines, a share that has been rising steadily. Moreover, around 90% of the sport utility vehicles and high-end cars sold in the country run on cheaper diesel than on the more expensive petrol. While buyers choose economy, experts say their choice is hurting the environment.
Credit: Center of Science and Environment
Diesel vehicles are estimated to emit more pollutants than their petrol variants. Analyses of the smoke sent out by diesel vehicles show that it contains worrying levels of ultra-fine particulate matter which can travel deep into the respiratory system, causing ailments such as emphysema and cancer.
The Centre of Science and Environment in Delhi, for instance, says that diesel cars emit three times more nitrogen oxide and 7.5 times more particulate matter than the petrol versions. These pollutants are more dangerous to health than carbon dioxide, which diesel cars arguably emit less.
Costs and benefits
The preference for diesel cars, experts assert, is setting off a process of “dieselisation”, leading to grave health hazards. “More driving results in more fuel use; more toxic pollution per km; more warming per litre of carbon-rich diesel burnt; and, more warming due to its heat-absorbing black carbon emissions,” says CSE in a report on diesel pricing.
In its order this month, the Supreme Court put public good above everything else.
“It is noteworthy that diesel vehicles of 2000 cc and above and SUVs are generally used by more affluent sections of our society and because of the higher engine capacity, they are more prone to cause higher levels of pollution,” a bench headed by Chief Justice TS Thakur said. “A ban on registration of such vehicles will not, therefore, affect the common man or the average citizen in the city of Delhi.”
The order also cracked down on diesel-run trucks and commercial vehicles. “No goods vehicle which is not bound for Delhi will be allowed to enter” the capital from the entry points on the two national highways, it said. Any truck that does pass through Delhi will have to pay double the “green tax”.
The decision was in keeping with the green push of the Delhi government, of the National Green Tribunal, and of the Delhi High Court, which had barred app-based taxi services such as Ola and Uber from running diesel cars in the capital.
Diesel vs Petrol
These moves are welcomed by environmentalists. But they add that there is a need to address a deeper problem: India’s relaxed emission standards.
“As per the standards, a diesel car is legally allowed to be at least six times as polluting as a petrol vehicle in India,” said Vivek Chattopadhyay, a researcher working on air quality and pollution at CSE. “Petrol vehicles, hence, are cleaner than diesel ones, which is odd since the playing field is legally not level and there’s nothing that the government is doing about it.”
Credit: Center of Science and Environment
Chattopadhyay explains that the latest generations of diesel engines emit less poisonous smoke than, say, those manufactured a decade ago. However, Indians hardly benefit from these advances since lax Indian emission standards allows manufacturers to continue producing polluting vehicles.
India’s emissions norms generally lag behind European standards for diesel and petrol vehicles. At present, about 14 cities in India follow Euro IV standards, which are nine years behind the more stringent norms currently in place in Europe. The contrast is even starker in the rest of the country, which by following Euro III norms is 14 years behind Europe.
“Euro III diesel cars emit 7.5 times more toxic particulate matter (PM) than comparable petrol cars,” CSE says in its report based on data made available by Pune’s Automotive Research Association of India. “This means that one diesel car is equal to adding 7.5 petrol cars to the car fleet in terms of PM emissions and three petrol cars in terms of NOx emissions.”
Credit: Center of Science and Environment
“This clearly reflects the flawed and lax emissions standards that allow diesel cars to emit more NOx and PM compared to petrol cars,” says CSE. “Total air toxics from a diesel car that are very harmful and carcinogenic are seven times higher than petrol cars.”
Experts say that carmakers have been allowed to get away with manufacturing highly polluting cars because of India’s slow adoption of European standards. As a solution, many of them suggest skipping Euro IV in some cities and implementing Euro V or Euro VI standards directly to curb pollution.
A 2011 study by the Indian Institute of Technology-Delhi, for instance, says the only way to limit PM 2.5 levels in Delhi’s air despite the five-fold rise in its vehicular population is to implement Euro V standards at the earliest. However, the government’s target date for the adoption of this standard is 2020. And Euro VI standards are expected to be implemented in India only in 2024.
At a time when 80 people are dying of poisonous air every day and hundreds are falling sick, waiting a decade for cleaner emission standards may be a bit too late.