Mahanagar Gas



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.

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 inflammability 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.

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).

What are the dimensions and weight of a CNG cylinder ?

CNG cylinders are manufactured from a special steel alloy and are seamless in construction. Their compact size allows them to easily fit into a small car. An empty CNG cylinder with a 50 litre-water-carrying capacity weighs 48 kg (approximately), and has a length of 835 mm and a diameter of 316 mm. The 50 litre capacity cylinder is the one most regularly used in CNG kits but cylinders with 45 litre, 55 litre, 60 litre and 65 litre capacity are used as well.

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 refuelling 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 Mumbai?

CNG driven cars may be refuelled outside Mumbai as CNG is presently available in 41 different cities of India. CNG corridors are available on Mumbai-Pune, Mumbai-Surat-Bharuch-Ankleshwara-Ahmedabad route.

Is CNG environmentally friendlier than any other fuel?

Yes, it is. As CNG mainly consists of methane which is the simplest hydrocarbon, it is a much cleaner and efficient fuel. The use of CNG significantly reduces harmful exhaust gas emissions like carbon monoxide, nitrogen dioxide and sulphur dioxide which causes harmful diseases like cancer, asthma etc. CNG also helps in reducing the effects of global warming.

Are cylinders used for filling CNG safe?

Cylinders used for storing gas are designed with very high safety factor in accordance with global standards. These cylinders are tested and certified for usage by statutory authorities and each cylinder is defined with an expiry date of usage after which they are to be tested again for safe use. These cylinders have been designed to take impact of collision in case of accidents. However, as per Gas Cylinder Rules, 1981, the cylinder should undergo hydro-stretch testing every 3 years to check pressure tolerance.

Which type of diesel powered Commercial Vehicles can be converted into CNG?

Almost all popular LCVs and HCV model’s CNG kit with payload range from 1 ton to 16 ton is available for BS-II models and BS-III kits are expected by November 2013. These vehicle  models include: Tata 407, 709, 909, 1109, 1613, Mahindra Pick up, Load King, DI 3200, Eicher 10.5, Swaraj Mazda Supreme, Sartaj, Tata 1512 Bus, 909 Bus, AL 1516 Bus, TI 3500 mini Bus etc. CNG Kit for Tata Ace is also under process with i-CAT.

What is the cost of converting a diesel vehicle to CNG?

The cost of converting a vehicle to CNG depends on the type of your vehicle and CNG kit and number of cylinders you want. Presently, the cost of conversion ranges between Rs. 1, 25,000 to Rs. 3, 50,000 (approximately). Tata 407, 709, Mahindra DI 3200- 1.5 Lac, Tata 909, 1109 and AL 1613 other HCVs – 3 Lac, Mini Buses-Buses (Tata & Ashok Leyland)- 2 Lac to  3.5 Lac.

Are Factory fitted CNG variants of commercial vehicles available?

Yes. All major vehicle manufacturers like TATA, Mahindra, Eicher, SML etc have CNG variants of their popular models like- Tata Ace, Magic, Xenon, 407, 709, 909, 1109, 1512 Bus, 1616 Bus, 909 Bus CNG Hy bus Mahindra Pick up, Maximo, Loadking, DI 3200, Eicher 10.5, Skyline Bus, SML- TI 3500 Bus, Supreme, Sartaj, Force Motors Trump20, Traveler minibus Ashok Leyland Dost, Bus 1613 etc.

Does CNG kit require servicing ?

CNG kit is safe and simple. It gives years of trouble free operation. It doesn’t require frequent servicing. Just as for all other fuels, it is advised to have routine services. An authorized person should be consulted for service. As per Gas Cylinder Rules, 1981, the cylinder should undergo hydro-stretch testing every 3 years to check pressure tolerance.

Can CNG kit co-exist with diesel engine in a Commercial vehicle ?

No. Dual fuel option in case of a diesel vehicle is not available as CNG requires Spark Ignition (SI) engine whereas Diesel engine has compressed ignition. However multiple CNG cylinders installed in CNG powered commercial vehicles gives ample time to refill CNG before it is completely drained off.

Impact of CNG kit on the payload of a vehicle.

Factory fitted CNG vehicles have the same payload that of a diesel vehicle, however in case of retro fitment payload of the vehicle is reduced to the tune of cylinders weight only.

What is the operational life of diesel and CNG variant of Commercial Vehicle in Mumbai?

Factory fitted CNG vehicle can ply in Mumbai for 16 years from date of registration. Transporter Commissioner’s office has also clearly stated that any commercial vehicle plying in Mumbai city on Diesel has a life of 8 years; however, if converted to CNG the same vehicle can ply for 16 years from original date of registration. For example if a diesel vehicle is converted to CNG after 1 year will have life of 15 years on CNG and if converted in 2nd year the live of vehicle on CNG will be 14 years and so on. Therefore, early conversion of diesel vehicle in to CNG will result not only in extension of vehicle life but also more savings on fuel cost. 

Are CNG powered commercial vehicles economical as compared to diesel variants.

Though the initial CNG vehicles cost is more than diesel but in long run CNG powered vehicles helps in saving overall operational cost. CNG powered commercial vehicles are 34% economical as compared to diesel vehicles in terms of avg. operational cost. LCVs with average running of 50 km per day can easily recover the Kit cost in 2.5 years.

Is there any finance option also available for retrofitting CNG kits of Commercial Vehicles?

Yes. Some leading automobile refinancing companies like Cholamandlam and Shriram Finance have this facility of financing CNG kits for Commercial Vehicles. For free CNG commercial vehicle demo or any further queries write to:

Who can do retro fitment of CNG kit in commercial Vehicles?

There are 6 ARAI and RTO authorized workshops in Mumbai for retro fitment of CNG kits in commercial Vehicles. M/s Shrimankar Auto Gas, (Sewree), M/s Green Globe Fuel Solution, (Mulund), M/s Chunnilal, (Bhandup), M/s Mars Ignition, (Mira road), M’s Lotus, (Powai), and Mr. Dhingra Turbhe (Navi-Mumbai). For further details visit: