For a nation that invented the zero and is so proud of its prowess in information technology, we seem to be completely clueless about the difference that one zero or two zeroes can make to a number. Take the confusion, deliberately created, on the alternative to CNG - the wonderfully "clean" diesel. Proponents talk publicly that ultra-low sulphur diesel (ULSD) as an easier and cleaner alternative. The Tata Energy Research Institute (TERI), major automobile manufacturers and oil industry have all been on the roll, advocating ULSD and arguing that the experts who recommended CNG clearly did not know their science or public policy.

But when these same agencies were asked to make presentations to the Environment Protection Control Authority (EPCA), which had been asked by the Supreme Court to define what is clean fuel, there was a different story. Each one of the organisations, including TERI and the Ministry of Petroleum and Natural Gas, argued that low sulphur diesel (LSD) should be used in Delhi and defined as a 'clean fuel'.

So what is different between LSD (recommended privately) and ULSD (advocated publicly)? The difference quite simply is between existing diesel in Delhi and the best diesel in the world, which has next to no sulphur content and reformulated to reduce other toxic components of the fuel like PAH. The difference is between 0.05 per cent and 0.001 per cent sulphur, or to make it even clearer, between 500 parts per million (ppm) of sulphur and 10 ppm of sulphur. But the confusion which has confounded our media who invariably get the two mixed up, has served the purpose of polluters by presenting an option (which does not exist), making people feel that there is an easy alternative which was not considered and providing a cop out - do nothing to implement the court order on CNG because there is so much confusion about what is better.

It is also important to understand why 10 ppm is a possible clean alternative. The low sulphur content at that level allows manufacturers to install a continuously regenerating trap to control emissions of the tiny and deadly particulates. The technology, uses very (ultra) low sulphur diesel with a particulate trap and a catalyst. If the sulphur level is higher, the efficiency of the particulate trap is very low. Monopoly sellers Engelhard and Johnson Matthey make tall claims for their traps, but the truth is that there is little evidence that traps work with more than 50 ppm sulphur. These same LSD/ULSD experts talk about CNG being an experimental technology!

But ULSD with trap technology is comparable with CNG emissions and could be considered an option for diesel vehicles. This is why EPCA recommended to the Supreme Court that ULSD could be defined as clean fuel but not alone, as a package with particulate traps, advanced vehicle technology and, most importantly, a verifiable system of preventing adulteration because without this the clean diesel could be even more dirty than what we have today and the trap would go for a six.

So why is it that these organisations that speak for ULSD are not endorsing EPCA's recommendations to the court? It is simply because they are not looking for solutions to the air pollution problem, they are looking for problems in the CNG solution. Firstly, they know that ULSD plus trap technology is not a viable option at this moment. TELCO, for instance, said clearly to EPCA in its written submission that it would take it a minimum of two years to introduce the trap technology in the country. The petroleum babus say they cannot produce ULSD nor are they prepared to import it. But clearly the problems are not insurmountable and if the agencies advocating the ULSD solution are serious, it can be done for the many cities that do not have CNG as an option and are choking with pollution.

The CNG opponents only want current diesel (500 ppm sulphur) with current vehicular technology (including buses with pre-Euro emission norms) to be declared clean fuel. What is indeed amazing is the role of the government, namely, the Ministry of Environment and Forests, in this dirty business. It has once again gone against its own committee, EPCA, to file an affidavit in court, arguing that the polluters' business as usual should be allowed. Not a shred of scientific evidence has been produced by this ministry to support its claim. T R Baalu, the minister is more worried about the diesel lobby than cleaning up the air. The government has suddenly shown an extraordinary level of energy and coordination just to make sure that CNG does not succeed. Why this energy now? After all CNG is also a commercial product, marketed by the same petroleum ministry.

We do know the following: CNG is hated by bus drivers because it cannot be siphoned off like diesel. CNG is hated by fuel pump owners because it cannot be adulterated. CNG is hated by officials and politicians because there are no spot purchases to be made. Imported diesel is a lucrative business because of the kickbacks on each litre purchased. On top of all this, there are the interests of oil companies and diesel auto makers who stand to lose business. Caught between this web of interests is the poor auto driver who stands in line for hours to get the gas that the vested interests don't want to provide. Real Ram Rajya, I must say.

-- Anil Agarwal