Compressed natural gas

Honda / Honda

Governors of 13 states that produce natural gas are asking Detroit car companies to make them a passenger car that runs on the fuel.

Advances in a drilling technique called horizontal hydraulic fracturing, or fracking, are making natural gas more plentiful.

The drilling technique has plenty of environmental critics, but Colorado Governor John Hickenlooper says it's safe when done properly, and he says natural gas is a better fuel than gasoline.