Natural gas vehiclesAvailable vehiclesPassenger Cars Natural gas can be used in all classes of vehicles - motorcycles, cars, vans, trucks, buses, lift trucks, locomotives, even ships and ferries. NGVs are available from many manufacturers including e.g. Opel, Fiat, Mercedes, Ford, Volkswagen, Citroen and Iveco. |
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Rank | Country | Natural Gas Vehicles | Refuelling Stations |
1 | Argentina | 1.650.000 | 1.400 |
2 | Pakistan | 1.550.000 | 1.606 |
3 | Brazil | 1.425.513 | 1.442 |
4 | Italy | 432.900 | 558 |
5 | India | 334.820 | 321 |
6 | Iran | 263.662 | 179 |
7 | Colombia | 203.292 | 310 |
8 | USA | 146.876 | 1.340 |
9 | China | 127.120 | 355 |
10 | Ukraine | 100.000 | 147 |
11 | Armenia | 81.394 | 128 |
12 | Bangladesh | 80.000 | 118 |
13 | Russia | 75.000 | 213 |
14 | Egypt | 69.376 | 99 |
15 | Bolivia | 64.828 | 87 |
16 | Germany | 55.272 | 700 |
17 | Venezuela | 44.146 | 149 |
18 | Thailand | 33.982 | 44 |
19 | Japan | 31.462 | 311 |
20 | Bulgaria | 25.225 | 9 |
Natural gas vehicles have a spark-ignition internal combustion engines (apart from dual-fuel models – see below) and are broadly similar to petrol vehicles but with different fuel storage and delivery mechanisms.
Since natural gas does not liquefy under compression, it must either be stored onboard vehicles as very high pressure compressed natural gas (CNG), usually at 200bar.
CNG fuel tanks have to be strong to withstand in excess of 200bar pressure, so they are usually made out of thick, heavy steel. NGV fuel tanks are therefore either large or heavy, which means natural gas is best suited for larger vehicles such as trucks, buses or vans. Nevertheless, favourable taxation policies have led to CNG cars being reasonably popular in some countries.
There are two fuel options for natural gas vehicles: Dedicated NGVs run only on natural gas, bi-fuel NGVs can switch between natural gas and petrol. There are advantages and disadvantages in all two options:
Dedicated (mono-fuel) NGVs can be optimised to run on NG by using higher compression ratios, which generally leads to higher engine efficiencies. This is possible because NG has a higher octane number than either petrol or diesel, which means the compression ratios can be increased without inducing knocking.
Many light-duty NGVs (cars and vans) have bi-fuel engines to eliminate the danger of running out of fuel and unable to find a NG refuelling station. This is more likely to be a problem with light-duty vehicles since they have more varied less predictable patters of use than trucks or buses and because cars in particular are not able to accommodate large fuel tanks. However, bi-fuel NGVs cannot be optimised to operate on natural gas and therefore do not show full potential for reducing tailpipe emissions.
(Source: International Association for Natural Gas Vehicles)