USA, New York

Time magazine has featured Delhi environmentalists Sunita Narain and Bhure Lal, acknowledging their efforts in reducing air pollution in Delhi, largely through the mass conversion of public transport to compressed natural gas (CNG).

Delhi's unique conversion program arose from a lawsuit filed by Narain, Director of the Centre for Science and Environment, in the mid 1990s, affirming the right of citizens to breathe clean air. The Supreme Court found in favour of Narain and imposed mandates forcing public transport operators to convert to compressed natural gas, even going so far as to appoint a committee, which included Narain and Bhure Lal, a government administrator, to enforce the ruling.

Despite significant hurdles, the program was a success, resulting in 10,000 CNG taxis, 12,000 CNG buses and 80,000 CNG rickshaws on Delhi’s roads.

The conversion model has since applied in several other cities throughout India, which now has almost 250,000 natural gas vehicles on its roads.