Environment scientists have, for the first time, apportioned the fuels, both diesel and petrol, across different categories of vehicles operating on Indian roads1.
Additionally, they have taken into account other minor fuel types like light diesel oil and fuel oil along with lubricants to generate a comprehensive and complete inventory of greenhouse gas emissions. This could be an important tool for policy makers to calculate precise national estimates of greenhouse gas emissions from the road transport sector.
The researchers at the Central Road Research Institute in New Delhi have tried to reduce uncertainties in the emission estimates of the road transport sector in India by apportioning the fuel types including lubricants and other minor fuel types in their study.
The sector is estimated to have emitted 27 million tonnes (Mt) of carbon dioxide-equivalent emissions in 1980 that increased to 59 Mt in 1990 and to 106 Mt in 2000, marking a 400 per cent increase over 1980-2000 periods. However, the total national carbon dioxide equivalent emissions have increased from 988 Mt in 1990 to 1485 Mt in 2000 with a compounded annual growth rate of 4.2 per cent. The road transport sector has contributed less than eight per cent to the total national carbon dioxide equivalent emissions during 1990-2000 periods. They found similar trends for other ozone precursor gases.
The researchers found that total petrol consumption had increased from nearly 1.5 Mt in 1980 to almost 6.5 Mt in 2000. Diesel consumption, on the other hand had gone up from nearly 7.2 Mt in 1980 to 26.8 Mt in 2000.
"It is not surprising since the number of motor vehicles have seen a 155 per cent rise in the decade since 1990. This study, therefore, suggests that documenting emissions by fuel and vehicle category-wise could go a long way in generating more accurate data on country-specific emissions with reduced uncertainties," says lead researcher Anil Singh.