CNG FAQ

What is CNG?
CNG stands for Compressed Natural Gas. It is a gaseous fuel and is a mixture of hydrocarbons, mainly methane in the range of 95%. Due to its low density, it is compressed to a pressure of 200 bar to enhance the vehicle on-board storage capacity.

Can a car, which is fitted with CNG kit, run on petrol after its CNG gets over?
Yes, after conversion to CNG the vehicle can run on petrol whenever desired simply by flicking a switch on the dashboard.

What is the cost of converting a vehicle to a CNG-friendly one?
The cost of converting a vehicle to CNG depends on the type of your vehicle and CNG kit. Presently, the cost of conversion ranges between Rs. 25,000 to Rs. 50,000 (approximately).

Is CNG Safe?
Yes, it is safe. The properties of CNG make it a safe fuel. It is lighter than air, and hence in case of leakage it disperses into the atmosphere rapidly. Its high auto-ignition temperature of 540 degrees centigrade as against petrol’s 360 degrees centigrade makes it even more safe fuel. CNG also has a narrow in flammability range of 5% to 15%, making it much safer than other fuels.

Which type of vehicles can be converted into CNG?
All spark-ignited engines can be converted to CNG, for which a specially designed conversion kit is required for the conversion process. The kit consists of a cylinder to be fixed in the boot of the car and other equipment’s to allow gas flow into the engine.

What is the capacity of a cylinder, and mileage from one fill? How does one get to know the quantity of CNG left in the cylinder?
A cylinder with a 50-litre water-carrying capacity is capable of carrying approximately 9 kg of CNG. This is equivalent to 12.5 litres of petrol and will allow a run of about 150-160 kms. for a medium sized 1300 CC car. An electronic fuel gauge fitted on the dashboard which is part of the conversion kit indicates the quantity of CNG left in the cylinder.

What is the pressure of CNG in a cylinder? Is refueling of a cylinder safe, given the pressure?
CNG cylinders are designed and built in such a way so as to withstand high pressure. The maximum pressure in a CNG cylinder is up to 200 bar. CNG cylinders are safe as they are manufactured as per specific requirements and tested before use, in accordance with international specifications and standards, and are duly approved by the Chief Controller of Explosives (CCoE). Moreover, they are provided with a pressure relief device (PRD) that consists of a fusible plug and a burst disc that ruptures in case of extremely high pressure and temperature.

Will my fuel expenses reduce after conversion to CNG?
Yes, the fuel bill on the basis of average running of vehicle reduces substantially when compared to other conventional fuels. Price of CNG is lesser than other fuels and also it enhances the mileage of your vehicle, making it the most economical fuel.

Will I lose my boot space if I convert my car to CNG?
On an average, vehicle owners lose about one third of their boot space when a car is converted to CNG. The boot space also depends upon the size of vehicle and cylinder make. However, people who wish to convert to CNG can still install carriers on their vehicles to compensate for the lost boot space

Does CNG have any harmful effect on the engine?
Owing to CNG's distinct features, it does not contaminate or dilute crankcase oil, giving a new lease of life to the engine. The absence of any lead content in CNG helps avoid lead fouling of plugs, thereby enhancing plug life. As CNG enters the engine in the form of a gas (and not as a spray or mist like other fuels), no carbon is generated during the combustion of CNG reducing the chances of wear and tear.

I have a Diesel engine - can it be converted, too?
Presently, the conversion cost for diesel vehicle is higher than the conversion of petrol vehicles and under the current technology it cannot run on duel fuel mode.

Can I refuel my car on CNG in cities other than Kanpur?
CNG driven cars may be refuelled outside Kanpur as CNG is presently available in many cities of India.