“All commercial transport buses in Karachi have been converted to CNG through a procedure more complicated than heart bypass surgery.Since you have a diesel engine to start with, you need to convert it to petrol in order to make it CNG-compatible,” says Bahdur Khan, a transporter.

All our buses, to begin with, had diesel engines. The conversion procedure or alteration involves taking out the injector to attach a distributor in its place. The heaters are taken out from each piston chamber and spark plugs inserted in their place. Finally, a carburetor is inserted at the air intake point alongside which a CNG kit can be installed.

“This costs around Rs40,000 to 50,000 but once converted you can’t go back to running the vehicle on diesel as the work involves drilling new holes in the engine block. And so — like the veins and arteries in the human body, which cannot be put back in their original places after a heart bypass — the engine can no longer be converted back to diesel. You’ll need a new diesel engine costing you over Rs125,000 if you want that. But if CNG stations are closed down what other option do we have?” he wondered aloud.

Most CNG-converted vehicles of today, therefore, cannot readily convert to something else that is cheaper and more easily available now. You need a new engine or kit to do that. According to Saqib Razzak, who runs a CNG conversion centre near Kala Pul, Karachi, the cost of a new CNG kit has now crossed Rs50,000. “But looking at the regular CNG load shedding, many are now taking to the idea of Liquefied Petroleum Gas (LPG),” he says.

“The cylinders of vehicles already running on LPG are taken out and refilled, but now there is a new system being introduced for the new LPG kits available in the market. An LPG kit for the latest fuel injector system cars costs Rs25,000 while one for cars with carburetors is for Rs20,000. The new system is just like filling CNG and is better as it is not just gas but liquid. LPG filling stations, too, are coming up. There are two, one on Sharea Faisal and one near the airport, in Karachi. And more will be set up as the demand increases.

About Liquefied Natural Gas (LNG), which everyone has been hearing about these days, the conversion expert says that it is still a distant concept. “Why talk about something that is still all talk. Conversion, costs and the rest associated with LNG will become real once the system gets properly introduced here,” he concludes. —Shazia Hasan