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The bottleneck

Print edition : Feb 16, 2002 T+T-

THE problems associated with running a compressed natural gas-driven bus fleet are plenty in Delhi, as was revealed at a recent seminar organised by the Delhi Transport Corporation (DTC). Fuel availability is only one of them. The lack of supportive infrastructure is the biggest bottleneck for a switch-over to CNG. Clearly, the huge cost of creating this infrastructure is a factor that inhibits the quick introduction of CNG. For handling the entire public transport system of Delhi, it is estimated that about 100 mother and online stations would be required. The court has directed the setting up of 80 CNG outlets (Indraprastha Gas Limited (IGL) has not implemented the order so far), of these only about 10 are mother and online stations.

In order to achieve a daily target of 225 km, the fuel tank of a bus has to be filled on a daily basis and, because there are not enough filling stations, this has entailed an enormous dead kilometreage (estimated to be 13,000 km a day), which in turn has affected the daily target. In contrast, meeting the emission norms based on petrol or diesel does not entail the creation of new dispensing infrastructure. In order to achieve the required specifications, only process technology needs to be upgraded.

The initial allocation of CNG for the Delhi transport system was 0.15 MCMD (million cubic metres a day). The demand, however, is 0.50 MCMD and it is projected to go up to 1.8 MCMD if the court's orders are complied with. The Ministry of Petroleum and Natural Gas has made it clear that the demand cannot be met and that the import of liquefied natural gas (LNG) can begin only after about three years. Also, domestic production is stated to be declining. The Ministry has also rejected IGL's claim made before the apex court that there was enough gas, saying that IGL, being a private company, was not competent to make such claims. Already private vehicles - with retrofit dual-fuel engines - are being denied CNG supply.

The capital cost for a new CNG-run bus is considerably higher than a new diesel bus: while a Bharat Stage-II (BS-II) diesel bus costs about Rs.10 lakhs, a CNG bus costs Rs.16 lakhs. So in attempting to convert its fleet (it has so far procured 2,120 CNG buses) the DTC has incurred an enormous expenditure. Moreover, the cost of repairs and maintenance of CNG buses is Rs.1.8 a km as against 60 paise for a diesel bus. All this money could have been more purposefully utilised in procuring more BS-II diesel buses and upgrading the existing fleet to BS-II in order to meet the court's laudable directive to expand the fleet to 10,000. This improvement would itself have reduced the overall vehicular pollution as bus transport is the least polluting per passenger transported.

As regards the performance of the vehicles, a number of problems have cropped up. These include gas leakage, low clutch life, the monsoon problem, the distributor coil pack problem, insufficient pick-up at high loads, starting trouble, engine/cylinder head failures, repeated failure of the catalytic converter and high oil consumption Failure of the catalytic converter would also imply higher levels of carbon monoxide (CO) and hydrocarbon (HC) pollutants from a CNG vehicle.

Although the twice-extended court deadline for conversion expired on January 31, and diesel vehicles continue to ply on Delhi's roads, the Delhi government intends to file an affidavit, placing the Mashelkar Report's recommendation of multi-technology option in its defence. Some people have argued that this would amount to contempt of court. It must, however, be pointed out that Mashelkar Report provides only a framework and guidelines for a national policy.

It in no way precludes individual States or cities from taking specific measures. For instance, the Supreme Court can still direct that its order be implemented and there will be no contradiction with the report.

Indeed, an important question that arises in the wake of the report is what the fate of CNG vehicles already on the road will be. Because, if however, diesel buses are allowed to ply, it could result in an unfair advantage to their operators because of higher profit margins as compared to CNG. The only way out seems to be a government subsidy in the operation of CNG buses so that they remain competitive. This is unlikely to happen given in the current economic situation of the Delhi government.