This section outlines the many technical options and fuels available which have the potential to reduce the environmental impacts of new buses.

• Cleaner conventional buses meeting more stringent emissions standards.
• The advanced diesel bus uses advanced engine systems and aftertreatment emission reduction devices, usually in conjunction with lower sulfur fuel.
• The compressed natural gas (CNG) bus uses a spark-ignition engine to burn natural gas, which contains mostly methane obtained from fossil resources.
• The liquefied petroleum gas (LPG) bus uses mostly propane gas for combustion.
• The ethanol bus runs on alcohol which can be produced from a variety of renewable biological resources.
• The battery electric bus is powered by electrochemical batteries which are charged using electricity from stationary power plants.
• The hybrid electric bus uses a combination of electric batteries and a combustion engine for its propulsion.
• The fuel cell bus employs a novel technology totally different from the internal combustion engine, which converts chemical energy directly into electric energy used to power the vehicle.
  

You can access the sub-topics in this section by clicking on the above links or by clicking on the navigation links to the left hand side of the page.