For a car, which is better LPG or CNG?

I have a car, should I fit a CNG or a LPG kit? This is a usual question many people ask. In this post I am not giving any direct answer to this question. But instead I would tell you the Plus and the Minus points of each of these and you find it out what’s suitable for you.

So let’s start with CNG (Compressed Natural Gas). I had 1996 Esteem and I had fitted a CNG Kit into that. I had fitted CNG into my car because my daily running is of 60 Km and CNG is cheap cost around Rs 24 per Kg (in Mumbai).  So it’s a lot of saving.

When you run a car on CNG, the car would give you around +3 Km/kg mileage. For example if your car gives you 10km/ltr on petrol, on CNG it would give you around 13 to 14 Km/Kg.

So far, so good, now let me list down the negatives. First, the initial investment is very high at around Rs 36 to 40K. If your daily running is not high, then this seems to be no good justification for such a large investment which is a depreciating asset. Secondly if your daily running is high, then the standard CNG cylinders available are of sizes 10, 12 and 14 Kg of which 2 Kg is reserve. So you would have to frequently have to visit the gas station….and by the way the gas station can only fill your cylinder full if they have enough pressure. Also these cylinders are huge and heavy in size, eating all you boot space, especially in small cars. And in case if you are planning to move out of metro cities, then there are only limited numbers of CNG stations outside major Metro cities. Also you would find that there is a pickup drop and this is really evident when the Air condition is running.

Let’s move to LPG (Liquefied Petroleum Gas). The initial investment is low, at around Rs 19 to 23K. You can have a custom made cylinder for LPG which can be fitted in the spare tyre space of your small car and still hold around 20 Kg of gas……because the gas is liquefied. As LPG is more combustible, the Pickup is improved. You would find more LPG stations as compared to CNG. For all you guys who love to break The Law, incase of emergencies, you can connect a domestic LPG cylinder to your car.

The negative points include that when you run a car on LPG, the car would give you around -2 Km/kg mileage. For example if your car gives you 10km/ltr on petrol, on LPG it would give you around 8 to 8.5 Km/Kg. Since LPG being around Rs 39 per Kg (in Mumbai) this turns out to be almost same as running cost on diesel.

There are also myths that running a car on CNG decreases its life. I don’t know how true this is, but as the experts say that if you take care of your engine and check the oil level at regular intervals then there are no harmful effects on the engine. I suggest if you opt for an engine oil specially made for engines running on CNG, I used SAE 20W50.

If your car is under company warranty, then make sure with your car manufacturer that fitting any external kit to your car voids the warranty. These days you get factory fitted LPG kits with quite a few cars, so if you are buying a new car, look for this option if it fits your criteria of car.

Well these were my inputs, do reply to this post and share your thoughts, questions, etc. and happy motoring…!

Related Post:
Things to be considered before fitting CNG or LPG in a car