CNG Vehicle Characteristics

• Here is a short video about CNG vehicles.  http://www.youtube.com/watch?v=nAa450Itk3s 
  
• Link to a short article about CNG taxis in Chicago.   http://chicagobreakingbusiness.com/2011/01/chicago-adding-natural-gas-taxis.html 
  
• A CNG powered engine is about 19% efficient.  That means that of the total amount of energy that is released when you burn natural gas in the engine, about 19% of that is used to make the car move.  The rest of the energy is lost as waste heat from the process of combustion.