Delhi ranks worst in terms of overall toxic emissions, heat-trapping emission and energy consumption, a study by think tank, Centre for Science and Environment (CSE) noted on Friday.
The study titled 'The Urban Commute' made an assessment of the 14 most populous cities of India based on release of particulate matter (PM), nitrogen oxides (NOx), heat-trapping carbon dioxide (CO2), and energy consumption from travelling practices.
These cities include Delhi, Mumbai, Kolkata, Chennai, Bengaluru and Hyderabad (categorised as megacities); and Ahmedabad, Pune, Jaipur, Lucknow, Kochi, Bhopal, Vijayawada and Chandigarh (referred to as metropolitan cities in the study).
"The analysis reveals that in Delhi, the sheer effect of population, volume of travel and highest vehicle stock has eclipsed the benefits of having CNG," said Anumita Roychowdhury, executive directorresearch and advocacy, CSE.
This is despite the fact that most of Delhi's parameters are better than other megacities -- such as rate of trip generation per person, average trip length and public transport share due to Metro.
"Per day, Delhi generates 20-30 mn more trips than Kolkata, Chennai, Hyderabad, Bangalore," it adds.