IT seems that a new study from Harvard University in usa has vindicated the position of the pro-diesel lobby that compressed natural gas (cng) is also very polluting. The report started appearing in newspapers, conveniently on the very day that the Supreme Court was to hear the case on moving diesel buses to cng. Copies of this report that "conclusively" proved that cng emitted nanoparticles (particles less than 0.1 micron) as against the information that diesel emitted fine and ultra-fine particles (particles of 2.5-1 micron) mysteriously landed on the desks of Delhi government officials. By July, with the government failing to implement the court order, this campaign had assumed gigantic proportions. Even the Lieutenant Governor of Delhi went public saying that cng was not desirable.
So what is this study all about? A close look at this six-page study done by the Harvard Centre for Risk Analysis in January 2000 shows that firstly it is only a preliminary survey that quotes rather vaguely from non-referenced studies. It says, "some studies suggest that cng emits more ultra-fine particles than diesel". Secondly, it is obviously biased in the selective information it quotes. Thirdly, it lack credibility because it is funded by Navistar, one of the world's leading truck and (diesel) engine manufacturers.
The following week, Parvez Hashmi, the transport minister and the man responsible for implementing the Supreme Court's order cited a December 1999 us study prepared by the General Accounting Office (gao). The report, he said, makes it clear that the us has a "very small proportion (5 per cent) of the transit bus fleet running on alternative fuels like cng " and that cng has inherent problems. The implication was that it was not possible for Delhi to move to cng .
But once again take a look at the selective use of the information in this "misinformation campaign". The gao report itself says that natural gas buses have a promising future. Hashmi also does not care to note that the us Department of Energy (doe) says that the discussion material in this report is "loosely based on informal conversations and interviews with a small industry group". The department says that the gao report gives the wrong impression that cng has technical problems as much of the report dwells on poor fleet experiences in the late 1980s and early 1990s. Since then market conditions have changed substantially. For instance, says this department of the us government, nearly 20 per cent of all new bus orders are now for alternative fuel, primarily natural gas.
What Hashmi forgets to say is that because of the growing success of cng , the us government is now encouraging Interstate Clean Transportation Corridors - highways where cng will be available throughout the route. He also does not care to cite that the new regulations in California mandate that operators with more than 15 buses must only replace their old vehicles or buy new vehicles that run on alternative fuels. usa already has 87,500 natural gas vehicles and over 1,000 cng outlets.
This is not to say that creating myths about cng is a monopoly of Indian industry. The international diesel lobby is fighting the move to switch to alternative fuels too. However, in India, where both information and scientific ability are limited it is easier to spread half-truths and try to subvert court orders. In April 2000, fed up with this trend, the us Department of Environment issued a press release, Natural Gas Buses: Separating Myth from Fact . This reflects on each point that is being used to confuse Delhi's decision-makers.
For instance, one argument used to discount the cng option is the high cost of converting a diesel engine to cng . However, what is not said is that while a cng bus has a high initial cost, it has lower operation and maintenance costs. Also, what is not said conveniently, is that when estimating the cost of the diesel option one has to take into consideration what it will cost to reduce the emissions of a diesel bus to the level of a cng bus. There are numerous studies to show that there is a very high cancer risk involved in the use of diesel because of tiny particulates and Delhi has a bad problem of particulates. The alternative proposed by Indian bus manufacturers is that Delhi should adopt Euro ii buses instead of cng . But Euro ii and even Euro iii (adopted in 2000 in Europe), buses would still emit ten times more particulates than cng . The only viable option currently that competes with cng is to go for Euro iv buses, fitted with catalyst-based diesel particulate filters, using ultra-low sulphur diesel, where the sulphur content is less than 15 parts per million (ppm). Compare this to Delhi where after much chest beating the government has succeeded in getting "low" sulphur diesel which has a sulphur content of 500 ppm. Think of all the costs involved then?
That all this is happening at a time when our country is thinking, according to newspaper reports, of sending a mission to the moon to demonstrate its scientific prowess is incredible. We will only go down in history as being scientifically so incompetent that we could not even make a cng engine work.
- --- Anil Agarwal
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