[wheelguy]

At present, diesel buses give a mileage of 3km per litre of diesel while it will be 4km per kg of CNG.

Nagpur: The move to convert 230 odd diesel standard buses into CNG will increase longevity of these buses by seven years.

Presently the NMC has a fleet of about 437 buses including 237 standard, 150 midi, 45 mini and five electric buses. Of these, the lifespan of 237 standard buses procured in 2010 under Jawaharlal National Urban Renewal Mission from central government, are all set to expire next year. As per motor vehicle rules, any buses that have crossed 10 years life or run for about eight lakh kms are entitled to be scrapped. However, to overcome this, the NMC is replacing the diesel engine with CNG kit in all the standard buses. “The job was undertaken early this year and so far has succeeded in converting 12 diesel buses into CNG. Of them, 10 have already started plying on city roads,” said a senior official from NMC’s transport department.

Conversion of diesel-run buses into CNG will make way for eco-friendly vehicles over a span of one year to reduce the pollution in the Orange City. The NMC has entrusted Rawmatt Industries Private Limited to convert its standard diesel bus into CNG by installing a CNG kit costing Rs3.25 lakh. The firm will recover the amount from the operators by charging Rs5 extra for every kilogram of gas.

Though life of the buses will increase by seven years, the NMC should ensure proper maintenance of the red buses. At present, all the three red bus operators are giving least priority over maintenance and it can be gauged with the fact that buses are plying with broken windowpanes, damaged seats etc.

Source: ET Auto

[sgiitk]

Please tell the Delhi / NCR chaps. They have the money but by all accounts are sleeping on it. We the NCR residents will be most grateful. i have been coming here for the past decade, but never seen this.

[Anwesh]

They should have taken advise from other municipal transport undertakings before getting into this. IMO this is a foolish move . CNG has been a problematic and loss making proposition in the medium and long term.
The issues are :-

1) About 40% power loss in the converted engine. Buses struggle to climb flyovers.

2)6 cylinder engine buses have to return to the depot by the afternoon for refilling. A diesel bus can run for the entire day once it leaves the depot in early morning on a full tank. The loss of time and dead milage on a CNG bus due to this problem leads to losses.

3)To overcome this issue, BEST and NMMT asked AL to fit extra gas tanks behind the rear axle on buses supplied under JNNURM I. A majority of these buses suffered chassis and body cracks in the area behind the rear axle.

4) A very through and systematic maintenance schedule is required for these buses to maintain reliblety and safety standards, increasing overall cost of operations.

Due to these issues, as an interim measure, both BEST and NMMT shifted back to buying Diesel powered buses and are now moving towards electric.

Regards,

[Grr7]

Diesel to CNG conversion was used around 10+ yrs ago when all diesel buses were banned from the roads of Delhi.

There were new (less than an year) old diesel buses of the transporters with big EMIs pending every month, disbanded from Delhi roads.

At that time, there were CNG conversion kits (basically changing the head of the engine) and other modifications that converted conventional diesel buses into CNG running buses.

Though not as reliable and powerful as the company fitted CNG buses, the converted buses were very much operational in Delhi and with fair amount of success.