Natural Gas Vehicles
2007 Environment Friendly City Gas
City Gas in Japan 2007
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Environmentally Friendly City Gas
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Safety Measures
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Industrial and Commercial Use
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Gas Cogeneration System
Natural Gas Vehicles
R&D for City Gas Use
International Relations
Environmental Preservation and Recycling
Relationship with the Local Community
 

Natural gas vehicles (NGVs) have impressive environmental credentials. They emit no SOx (sulfur oxides), soot or other particulate matter, and compared to gasoline and diesel powered vehicles, their emissions of NOx (nitrogen oxides) and CO2 (carbon dioxide) are relatively low. NGVs come in a variety of types, from minicars to (more commonly) trucks and buses ﾐ a feature that sets them apart from other low emission vehicles.

The number of NGVs on the roads passed 10,000 in November of 2001, 30,000 in December of 2006 and a campaign is now underway to make these vehicles a common sight on Japanﾕs roads.
　
･ Comparison of exhaust gases
 
･ Comparison of CO2 emissions while traveling
Comparison of CO2 emissions while traveling
 
･ Number of CNGVs and rapid refilling stations
Number of CNGVs and rapid refilling stations
　
Symbol for NGVs 　 Example of CNGV construction(compressed natural gas vehicle)
Apart from the fuel system, there is little difference in the construction of an NGV and a conventional gasoline or diesel-powered vehicle. The natural gas fuel is compressed to a high pressure (20MPaﾅ204kgf/m2) and pumped into the vehicleﾕs gas tank, from which it is supplied to the engine through a fuel pipe after first passing through a pressure regulator.
Symbol for NGVs
　
Package type quick charge station 　 First expressway Eco Station at the Kamigo Service Area on the Tomei Expressway 　 Natural gas vehicle CNG filling station (Eco Station)
Package type quick charge station 　 First expressway Eco Station at the Kamigo Service Area
on the Tomei Expressway		 　 Natural gas vehicle CNG filling station (Eco Station)
Truck 　 Garbage truck 　 Large bus 　 Bifuel vehicle (Sub fuel)
Truck 　 Garbage truck 　 Large bus 　 Bifuel vehicle
　
Gas insights
･ Types of natural gas vehicles
Natural gas vehicles may be classified as follows in terms of the type of fuel storage.
1. Compressed natural gas vehicles (CNGVs)
This type stores natural gas in a gaseous state at high pressure (20 MPa) in a gas cylinder. There are more than 35,000 CNGVs on the road in Japan.
2. Liquefied natural gas vehicles (LNGVs)
This type stores natural gas in a liquid state at a temperature of -162 degrees centigrade, in an ultra low-temperature container. Practical models are currently under development.
3. Adsorbed natural gas vehicles (ANGVs)
This type has the natural gas adsorbed by adsorption materials within the gas container and stores it at a pressure of a few MPas. It is now in the research stage.
Types of natural gas vehicles