:''NGV also stands for
National Gallery of Victoria''
A 'Natural gas vehicle' or 'NGV' is a
vehicle that uses
compressed natural gas (CNG) or, less commonly,
liquified natural gas (LNG)) as a clean alternative to other
automobile fuels. Worldwide, there are roughly 5 million NGVs
as of 2006, with the largest number of NGVs in
Argentina,
Brazil,
India,
Pakistan and
Italy. They are also popular in
Germany.
NGV's have the advantage of being potentially refuelled at home from existing natural gas lines with home refuelling stations that tap into such lines. Honda has pioneered such a system known as "Phill".
[1],
[2]
While existing gasoline-powered vehicles may be converted to CNG, an increasing number of vehicles worldwide are being manufactured to run on CNG. For example, in
Klang Valley,
Malaysia taxi companies converted their cars to NGV, greatly reducing the cost of operation.
GM do Brasil introduced the MultiPower engine in August 2004 which was capable of using NGV, alcohol and petrol as fuel, since its electronic fuel injection could adapt automatically to any acceptable fuel configuration. This motor was used in the
Chevrolet Astra and was aimed at the taxi market.
Although a localized problem, NGV refill stations can be scarce in some places, so cab drivers need to wait in long queues to refill.
Chemical composition and energy content
Chemical composition
The primary component of
natural gas is
methane (
CH4), the shortest and lightest
hydrocarbon molecule. It may also contain heavier gaseous hydrocarbons such as
ethane (
C2H6),
propane (
C3H8) and
butane (
C4H10), as well as other gases, in varying amounts.
Hydrogen sulfide (
H2S) is a common contaminant, which must be removed prior to most uses.
Energy content
Combustion of one
cubic meter yields 38 MJ (10.6 kWh). Natural gas has the highest energy/carbon ratio of any fossil fuel, and thus produces less carbon dioxide per unit of energy.
Storage and transport
Transport
The major difficulty in the use of natural gas is
transportation. Natural gas
pipelines are economical, but are impractical across oceans. Liquefied natural gas (
LNG)
tankers are also used, but have higher operating costs.
Storage
CNG is typically stored in steel or composite containers at high pressure (3000 to 4000 lbf/in², or 205 to 275 bar). These containers are not typically temperature controlled, but are allowed to stay at local ambient temperature.
LNG (Liquefied Natural Gas) storage pressures are typically at or just above the local atmospheric pressure (0 to 30 lbf/in², or 0 to 2.1 bar). LNG is stored at temperatures as low as -260°F (-162°C). At these temperature and pressure conditions, natural gas is in a liquid state. Storage temperatures may vary due to varying composition and storage pressure. LNG is far more dense than even the highly compressed state of CNG. As a consequence of the low temperatures, vacuum insulated storage tanks are used to hold LNG. These tanks are often referred to as dewars to credit the early cryogenic scientist
Sir James Dewar.
See also
★
List of natural gas vehicles
External links
★
CNG-NGV Community Forum
★
CNG Forum
★
About Natural Gas Vehicles
★
Alternative Fuels Data Center: Natural Gas Vehicles
★
International Natural Gas Vehicle Statistics
★
Vehicle Emissions Reduction: CNG
★
Liquid Natural Gas Fueling Stations Mapped on Platial.
★
Compressed Natural Gas Fueling Stations Mapped on Platial.
★
Rotarex Automotive
Europe
★
European Natural Gas Vehicle Assiciation
North America
★
What is Compressed Natural Gas?
★
US Department of Energy Consumers' Guide
★
Boost for natural gas cars: Home fueling
South Asia
★
Pakistan passes million-vehicle mark
★ Pakistan: Daily Times stories about cheap ($2000 - $3000) CNG cars:
[3],
[4]
★ India:
How New Delhi used CNG to ease pollution