cng vehicle

Come to Pakistan and 95% of all vehicles are on CNG.

The conversion kit (all Italian) comes at USD $ 500. The Gas is at 200 Bar Pressure.

There are over thousands and thousands of workshops doing conversion.

Give your car, pay the money, come back after 6 hours, start your car ,switch over from petrol to gas with a push button switch & vice versa and drive off.

Saving Vs Petrol 60%.

The wheels invented already who bothers about the technique now.

I agree, but remember that, CNG OR lpg is used in conventional piston engines, using the compression force already avaliable, this means that you have to inject a tiny amount of CNG (LPG) per stroke. That being said, CNG (LPG) is still a more pollution free source of energy.

Without bothering about the technalities, once the car is converted into CNG, it first starts on petrol (bulb #1 on) and then immediately switches over to gas (bulb #2 on).

There are 3 more bulbs that indicates level of CNG in the Pressure Cylinder mounted inside the truck. After each 20-25 km one bulb keeps going off and finally a red bulb is on indicating that you may have 10 km to get it filled up again at a gas station.

In case you run out the car stalls and shut down.There is a chage over switch, you press that and (bulb#1) lights up indicating now you are in petrol so you drive to nearest pump and fill up gas. Press change over switch (bulb#2 and #3,#4,#5 ) lights up indicating you are on CNG and the the 4-bulb tank volume.

The only thing you have to care about is the Air Filter which must be kept clean else the car may catch fire. Only one incident was reported till date in millions of cars/buses/trucks/rickshaws/vans running.

I keep 2 new air filters in spare which I change every 2 months.

In Delhi the use of CNG is compulsory for all public transport, because the pollution levels were getting out of control using petrol and diesel !

Oil companies have used CNG to run engines for over 60 years.

Do a search and you will come up with more information than you could ever want.

By the way, expect a 50% loss in HP when converting to CNG and really poor milage, 40 - 60% less.

I think you might have got your facts a bit mixed up, what (I think) you are referring to is coal gas, as was used in the Second World war to run buses in London. This thread is discussing Compressed natural gas, and the efficiency is infact slightly better than that of a petrol engine, also the mileage. Why isn't it used extensively, there are still fears (mostly unfounded) that the tank will explode!

I would like to add a few points here as there are a lot of incorrect statements in this thread. The gentlemans comments on Pakistan are correct.

• Natural gas has a higher octane than petrol.
• NG can be more efficient than petrol. A vehicle we have just converted which has still not been properly tuned at this stage ran for 187Km on a 60 wcl cylinder filled to 200 bar. This equates to 12 cubic Meters of NG which is equivelent to ~15 Litres of ULP. Mileage was a mixture of City and freeway = 12.4km / L (equivelant).
• CNG and (LPG) are so completely different that they should not be used in the manner of CNG (LPG). The differences are too numerous for me to start listing here.
• Not all conversion kits are from Italy although the Italians have been using Natural gas consistently since the 1930's. Kits are available from Argentina, Brazil, India, China etc etc etc. I would say that at this stage the Italian kits are the best but that is just a matter of time until better ones come out in Eurpoe.
• CNG is not injected in "tiny amounts" using "compression force already available". The vehicle mentioned above with reference to mileage is a I6 multipoint sequential fuel injected vehicle running on 100% ULP or 100% CNG.
• CNG is only used as a % substitute in some diesel engine.
• The first internal combustion engine was run on natural gas. Petrol became the preferred fuel as it was easy to handle being a liquid.
• CNG is increasing rapidly. Currently 6.6 Million vehicles around the world. Sth America has been leading this game and Pakistan is about to overtake them in numbers.
• CNG vehicle numbers and refuelling stations are increasing at 33.6% per year for the last five years.
• NG is the cleanest commonly available fuel.
• Natural gas has not been more widely adopted as a result of a lackof refueling infrastructure in most countries. Not because it is falsely percieved as being more dangerous than Petrol and Diesel.
• While we mention safety, in fact CNG is far safer than petrol, diesel and LPG. It is contained in cylinders that are engineered to a much higher level than other fuel tanks and being lighter than air will rise up and away from an accident site rather than sinking down and pooling around a leak or an accident site (Where there are potential ignition sources) as is the case with other fuels. In the case of other heavy fuels, a fire will result in a massive conflagration that may be further fueled by a leak. This will occur right where the any accident victims may be trapped in the vehicles. NG also has a very narrow range of flammability (5 - 15 ppm) outside of which it is non-flammable. When you hear of a gas cylinder explosion, it will be an LPG cylinder not CNG. The first ever death from a CNG cylinder in the US occured last month.
• Oil and gas companies HAVE been running engines on NG for a long time. It is the cheapest fuel for them as for many years they would just flare it off at a flare tower. Also Coke gas (or Town gas) has been used to run vehicles during both world wars in many countries around the world.
• Europe is heading down the NG pathway in a very big way. Watch this space.

Probably the biggest drawback for CNG is the amount of fuel that can be held onboard a vehicle. Being a compressed gas (it needs to be refrigerated to -237oC to be liquified) it is far less dense than a liquid fuel and therefore a CNG cylinder of an equivelent volume of a large LPG tank will only hold the equivelent energy of around 15 - 20 Litres of petrol. (or 20 - 26 Litres of LPG). Therefore a user needs to refuel more often.

Home compressors are available and more are coming on the market which will mean that a CNG vehicle can refuel from the home gas supply over night.

So there you go.

By the way Sharan. What country are you in? You can more than likely have your vehicle converted somewhere locally.

Are there valves, comparable to diesel fuel injectors, which can handle gasses at 200 bar? I want a valve which is fast acting and controlable with a minimum pressure drop when open.

I ran across a reference to a diesel locomotive running on CNG (in the Napa Valley,wine country, to minimize pollution), but the CNG was injected at low pressure.

You "guys" should meet Phill. It is a CNG filling station for consumer use. The Phill would be about 5K as I recall.

http://www.myphill.com/

I have met Phill. It is Slow and has a short life span.

That was a very informative and comprehensive post from Johnoz. The reasons for opting for CNG are obvious. The pollution is much lower from CNG vehicles.