This one side of the grass, the other is is very different.
The 55 KG cylinder gets up to 9 KGs of Gas. If he is getting 2.2/Kilometer, this means he gets 225 Kilometers in one full cylinder ((Rs. 55/2.2) x 9), which is absurd. No can can do that. I doubt even Mehran getting 225 Kilometers in one cylinder.
[JZ] - Mehran has 40 KG cyclinder as factory fitted and easily does 140 KMs without A/C and within City.. Even Cheverlot Joy does 110 Plus in City easily...
Normal 1300cc cars get up to 160 Kilometers on highways in one cyliner. But lets assume Honda City will do 170.
[JZ] - I've heard that City does more but lets stick to 170 so according to your calculation its 3 Rs/KM...
[CODE]So Rs. 55/KG x 9 = 495 (or lets say 500 to round the figure).
500 Rupees of gas can get one up to 170 kilometers, therefore
500/170 = 2.99 or Rs 3/KM.
Lets call this X.
X = 3.
Next, saying that Petrol is 4.17/KM is also his own car's economy. Not Honda City in general. His car is doing 4.17 Kilometer. 4.17 Kilometer means about 17 Kilometer/L (people are getting 19 in local). My car last time did 22.8 Kilometers per liter. But lets say my car has some magical powers, lets assume most people will get 21 KPL on this car if you drive at 100 km/h.
So 69.5/21 kpl = Rs. 3.30/KM.
Lets call this Y.
Y = 3.30[/CODE]
[JZ] - Lets assume you are calculating it right for long routes (even it is incorrect as CNG does little more and Petrol does little less)
My Question here... How about driving it within City and with A/C... You can hardly get 12 to 13 KM/L with A/C and within City and if you've a habbit like me (i.e. Sitting in car with A/C on while going with family on shopping) then you'll hardly get 11 KM/L on Honda City IDSI even with best fuel economy driving style.... (so its like 6 Rs/KM)
And to be very honest on CNG its atleast half as compare to Petrol i.e 3 Rs KM and within City with A/C on...
Note: I am talking about Lahore city... CNG here is like 48 Rs...and driving style within city is different as compare to ISB...
This is basic arithmetic. Even a child from the second grade can make these calculations. No car makes 225 Kilometers in one cylinder?
Now, you're saving 0.3 Rupees per kilometer.
After 133,333.33 (one lack thirty three thousand) Kilometers, you'll have paid the price of a CNG kit that costs 40,000 rupees.
If I am to calculate this for my own car, it would go something like this:
69.2 divided by 22.5 = 3.075.
Per kilometer is 3.075.
So per kilometer saving is 0.075 -- assuming the car does 170 on highways on CNG, I doubt that. MOST 1.3L cars (Liana, XLi, 1.6L Civic etc) do 160 max on CNG but lets go for 170. And lets suppose the price of the kit is 35000 (although there are CNG kits that cost even up to 60,000 very nice ones, but anyway..)
[CODE]35,000 divided by 0.075 = 466,666.66 Kilometers (at which the price of a 35,000 Kit is achived).[/CODE]
I drive 25 - 30 thousand kilometers a year. In my case, the price of the kit will be achived after many years.
Another VERY IMPORTANT point to notice is that if you drive carefully, Petrol costs less than CNG in local. People get up to 19KPL inside city (probably without AC) This is cheaper than CNG.
One more thing equally important is that even when you're running on CNG, you're also burning petrol everyday. Sometimes CNG finishes, the EFI cars always start on petrol etc. So we're not adding that at all.
People, make some calculations and research of your own too. Its not as difficult as it looks.
P.S: I have edited this post for the newer prices of Petrol.