Natural Gas Vehicles – Running on Clean & Safe Technology


Two decades ago, taking a stroll on Kochi’s streets was a relaxing and pleasurable way to good health. But not any more. Exhaust pipes from the rising vehicular population belch out pollutants ranging from carbon monoxide, nitrogen oxide, sulphur di oxide, hydrocarbons and particulate matter. An evening stroll in the bustling metro can leave you feeling nauseated and sick. With increasing migration into urban spaces being the trend across the country, the scenario for the future takes on nightmarish proportions.

Under the circumstances, Kerala Gail Gas Limited’s proposal to set up CNG refuelling stations at major bus stops comes as a breath of fresh air. The resulting conversion of Kerala State Road Transport Corporation’s fleet of pollutant-spewing buses to CNG-fuelled natural gas vehicles brings with it enormous economic and environment benefits.
The Road to Better Safety: More natural gas vehicles on the road will also mean better safety. It must be understood that natural gas vehicles operate on the same principle as diesel or petrol vehicles. In both cases, the transportation fuel is mixed with air in a four stroke engine cylinder. It is then ignited by a spark plug which moves a piston up and down.

CNG 20 Million

The US Department of Energy has attested that natural gas vehicles are as safe as petrol or diesel vehicles. Data collected has demonstrated that natural gas vehicles are extremely stable in actual operation. A US survey of 8,331 natural gas utility, school, municipal and business fleet vehicles (NGVs) that had done a total of 178.3 million miles revealed that the natural gas fleet vehicle injury rate was 37 percent lower than the gasoline fleet vehicle rate. Secondly, there were no fatalities compared with 1.28 deaths per 100 million miles for gasoline fleet vehicles and the collision rate for natural gas fleet vehicles was 31 percent lower than the rate for gasoline fleet vehicles. Importantly, out of the 8,331 natural gas vehicles surveyed, only seven were involved in fire incidents – and there was only one which was caused by failure of the installed natural gas fuel system.
What Makes Natural Gas Vehicles So Safe?
Natural Advantages: Its physical characteristics make natural gas a safe transportation fuel for vehicles. Natural gas is lighter than air. Therefore, in case of a post-collision leak, the chances of the gas harmlessly dissipating into the atmosphere are high. Once the gas dissipates, the danger of a fire is considerably reduced. On the other hand, a leak in a petro-fuelled vehicle leaves a highly flammable oil-puddle on the ground. Being toxic, the fuel contaminates the ground and water.
Natural gas also has a very limited range of flammability (5-15 percent) and a very high ignition temperature. This reduces the chances of a fire as compared to petrol or diesel (which have a wider range of flammability and lower ignition temperatures).
Better Design and Technology: The pressurized tank in which the gas is stored has been designed to withstand collisions and high temperatures. In fact, across the world, the natural gas vehicles that are manufactured and sold have to undergo the same crash tests as other vehicles. Natural gas cylinders are made of fibreglass and are much thicker and stronger than gasoline or diesel tanks. Technology today makes it possible to design cylinders that will not rupture even when fuelled over six times a day on a daily basis. Under normal circumstance, no gas cylinder fitted in a natural gas vehicle will undergo this kind of intensive use which it is designed to withstand. The cylinders manufactured are strong and sturdy enough to undergo a bonfire test and will not rupture even when shot with a 30 calibre bullet.
In an energy starved world populated by more and more people battling environment fears, natural gas vehicles seem to be the natural way to progress to a greener, safer future.