NGV

A natural gas vehicle (NGV) is an alternative fuel vehicle that uses compressed natural gas (CNG) or liquefied natural gas (LNG) as a cleaner alternative to other fossil fuels. Natural gas vehicles should not be confused with vehicles powered by propane (LPG), which is a fuel with a fundamentally different composition. Worldwide, there were 22.7 million NGVs by 2015, led by China (4.44 million), Iran (4.00 million), Pakistan (3.70 million), Argentina (2.48 million), India (1.80 million), and Brazil (1.78 million). The Asia-Pacific region leads the world with 6.8 million vehicles, followed by Latin America with 4.2 million. In Latin America, almost 90% of NGVs have bi-fuel engines, allowing these vehicles to run on either gasoline or CNG. In Pakistan, almost every vehicle converted to (or manufactured for) alternative fuel use typically retains the capability of running on gasoline.

As of 2009, the U.S. had a fleet of 114,270 CNG vehicles, mostly buses; 147,030 vehicles running on liquefied petroleum gas (LPG); and 3,176 vehicles LNG. Other countries where natural gas-powered buses are popular include India, Australia, Argentina, Germany, and Greece. In OECD countries, there are around 500,000 CNG vehicles. Pakistan's market share of NGVs was 61.1% in 2010, follow by Armenia with 32%, and Bolivia with 20%. The number of NGV refueling stations has also increased, to 18,202 worldwide as of 2010, up 10.2% from the previous year.

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