你从哪里信手拈来的？这个年代不懂不是个问题，态度才是个问题

“A regular gasoline-powered car averages 32 miles per gallon while a CNG-powered car averages 43 miles per gallon,” Darian says, referring to compressed natural gas.Dec 18, 2012

The Pros And Cons Of Natural-Gas Vehicle

Combustion of one cubic meter yields 38 MJ (10.6 kWh). Natural gas has the highest energy/carbon ratio of any fossil fuel, and thus produces less carbon dioxide per unit of energy.