CNG buses in Gujarat ‘tweaked’ to show they pollute more than diesel-run vehicles: Report
The report said that in one instance the stepper motor installed for efficient fuel use was removed and hence the bus was operating in the open-loop condition and causing more pollution
Ahmedabad: The Gujarat State Road Transport Corporation (GSRTC) “tweaked” retro-fitted CNG buses to show they cause more pollution to prevent the phasing out of the diesel-run buses, an Automotive Research Association of India (ARAI) report submitted to the state government has said. The report said GSRTC made several attempts to prevent the conversion of buses to CNG.
The report said that in one instance the stepper motor installed for efficient fuel use was removed and hence the bus was operating in the open-loop condition and causing more pollution. In another instance, the maintenance was done in a wrong and unsafe way with wiring tied up by cotton waste. The wiring was also disconnected for the fuel control valve in one of the CNG converted buses, thereby resulting in more fuel intake for emission.
A GSRTC official said there is little scope for switching their fleet from diesel to CNG because of the latest BS-VI emission norms for automobiles. He added GSRTC earlier converted buses to CNG but discontinued the process as BS-VI engines follow the strictest emission norms. “So, why should we convert them to CNG? Also, we have found that CNG pollutes more than diesel,” the official said, requesting anonymity. “BS-VI technology is very recent and GSRTC cannot scrap all the old buses and replace them with the new ones.”
The state energy department asked ARAI, an autonomous body affiliated with the Union heavy industries ministry, to carry out a comparative study of CNG and diesel buses for public transportation after a study by a Gandhinagar-based institute said CNG buses are not cleaner.
The GSRTC official tried to brush aside the issue saying the ARAI report, a copy of which HT has reviewed, is an old one. He added the corporation is exploring the option of running buses on LNG, a liquified form of natural gas. CNG is the compressed version.
ARAI report recommended GSRTC introduce/reintroduce CNG fuelled buses in an expeditious manner.
GSRTC, a state government undertaking, has a fleet of about 8,500 buses including those run on CNG. It planned to have 600 CNG buses. The CNG bus plan was scrapped citing high maintenance costs and frequent breakdowns.
The ARAI report questioned the credentials of the Gandhinagar-based institute to do the comparative study without certification experience. The study contains sweeping statements against CNG without firm evidence and contradicts years of published work worldwide on it being less polluting than diesel.
A second official said one way of tackling air pollution is to reduce the dependence on fossil fuels such as diesel and use cleaner fuels like CNG. “Electric buses will take time to ply on the Indian roads given the infrastructure it requires. Till then, CNG is the most preferred option.” He added converting buses to run on CNG in place of diesel reduces the cost of operation. The second official said it also tends to check the malpractice of diversion of diesel to the black market.