Compressed Natural Gas

Unlike the U.S., most passenger vehicles in Europe run on diesel fuel, not gasoline, and from a public health perspective, diesel emissions can severely exacerbate particle pollution during weather inversions like the one Paris is now experiencing.
Mar 19, 2014   The Atlantic Cities
Just as the power industry turned toward lower priced natural gas and away from dirtier coal, there are signs that trucks and trains are looking to lower priced liquefied natural gas (LNG) to replace diesel-powered vehicles, but there are challenges.
Apr 29, 2013   The New York Times - Energy & Environment
Delhi’s unpleasant pollution predicament, and its ensuing health consequences, are causing environmentalists, doctors and local officials to grow increasingly alarmed.
Jan 1, 2013   The New York Times
The city still known for its smog will not have its buses to blame - the last of its diesel-fueled ones retired Jan. 12 in a celebration. All but 7 of the 2,221 buses will be compressed-natural-gas powered; electric and gas-electric the remainder.
Jan 13, 2011   Los Angeles Times: Environment