How natural gas is used as vehicle fuel

Natural gas is needed not only for cooking, heating and power generation. It is also possible to fill cars with it. Natural gas as a vehicle fuel is much cheaper and environmentally cleaner than petroleum products.

Philippe Lebon was one of the first to propose using gaseous fuel. In 1801 he received a patent for an invention to pressurize gas and air by separate compressors and subsequently mix them in a special chamber. In 1860 a French inventor Etienne Lenoir developed the first operational internal combustion gas engine. He invented igniting the gas-air mixture in the engine with an electric spark.

The prototype of a modern NGV car – a self-propelled vehicle with an internal combustion engine – was powered by illumination gas (produced by distillation of certain coal grades). In 1894 natural gas was used as a fuel for railway transport in Dessau, Germany. However, NGVs were not widely used in the 19th century.

In late 1940s and early 1950s the USSR produced NGVs and developed a network of CNG filling stations. But the low level of gas supply and a relatively small scope of gas production in those times hindered the NGVs expansion.

What kind of gas is used for filling cars

Today’s vehicles are filled with different kinds of liquefied gas: methane (natural gas), propane, butane and their mixtures (so-called hydrocarbon gases). In addition, methane may be also used in its compressed state. This article particularly concerns natural gas use as a vehicle fuel.
In order to produce compressed natural gas (CNG), methane is pressurized in a methane compressor. Its volume is decreased by 200–250 times.
Liquefied natural gas (LNG) is produced by chilling gas to minus 161.5 °C. The gas volume is decreased by 600 times.

Why natural gas is considered environmentally friendly fuel

Emissions of a car powered by the ‘blue fuel’ are five times less harmful than those of a car equipped with a gasoline engine. This is a solid advantage of natural gas, because cars are the main air pollutant, especially in big cities. The conversion of cars and buses to natural gas can make the air cleaner and improve the environmental situation in cities.

 

Cost saving by filling car with methane

As of today, methane costs around RUB 12 per one cubic meter (equivalent to one liter of gasoline) in Russia. This is three times cheaper and provides less consumption than gasoline. Using NGV fuel in public transport, which covers long distances every day, is much more advantageous. For instance, if you convert 100 buses from conventional fuel to methane, you can save RUB 34 million per year because of the price difference.
Moreover, methane doesn’t contain impurities and, therefore, doesn’t produce sediments in the fuel system while burning. A gas powered engine operates longer and more efficiently.

Safe gas

Natural gas is the safest of all fuels available today. In the event of an accident methane doesn’t accumulate in depressions and doesn’t produce a flammable mixture of vapors and air. Since gas is lighter than air, it evaporates immediately, so its leakage is not hazardous.

Cylinders containing methane have very thick and robust walls. During manufacturing they are repeatedly checked to ensure pressure-resistance of the containers.

Natural gas – to engines

Nowadays, almost all major car makers produce methane-powered cars. The world leaders of the car industry – Volvo, Audi, Chevrolet, Daimler-Benz, Iveco, MAN, Opel, Peugeot, Citroen, Scania, Fiat, Volkswagen, Ford, Honda, Toyota – they all offer today series cars with engines running on CNG. These vehicles are in no way inferior to conventional gasoline counterparts and are very popular among car owners. There are more than 17 million methane-powered cars worldwide today and their number continues to grow.