The CNG Mess Delhi Today, All India Tomorrow?

THE capital city of Delhi, among the most polluted cities in the world, has been set by the Supreme Court upon a chaotic and painful course of having to ensure that all public transport buses in the city run only on compressed natural gas (CNG), either by buying new dedicated CNG-fuelled buses or by converting the older diesel-fuelled buses to run on CNG. To citizens of Delhi, it appeared that the transition was to take place almost overnight with effect from April 1, with a grace period later granted till September 30. In fact the Supreme Court’s orders that all Delhi’s buses would run only on CNG, along with other measures aimed at curbing vehicular pollution, were issued three years ago in 1998 following a public interest petition.


Since then, except for some measures mainly directed at taxis and auto-rickshaws and ordering a small number of new CNG buses and conversions of some older ones, the Delhi government did little to address the wide gamut of issues needed to ensure compliance with the court’s orders. On their part, operators of private buses, which account for the majority of buses in Delhi, did nothing either, with the result that only a few hundred buses were on Delhi’s roads on April 1 when the court’s orders went into effect, leading to complete chaos. Other important actors, such as the union ministries of petroleum & natural gas, environment and surface transport, were almost invisible and were content to let the Delhi government carry the burden and take the blame. Unfortunately, the Supreme Court too, which should have known of or anticipated the complexity of the problem and the numerous inter-departmental issues involved, did not do so and watched while things got out of hand.

It must be said that not too many others, like the media, environmentalists or NGOs, took much interest till the crisis boiled over. Since then there have been a plethora of statements by various authorities, and numerous articles and commentaries, furiously debating the pros and cons of CNG, especially as compared to other environment-friendly fuels, with a chorus of voices being raised against the singling out of CNG as the only option. As this article goes to press, the Supreme Court, acting upon the request of the solicitor general of India, has requested the Bhure Lal committee, set up earlier by it to assist on this issue, to also look at other “clean fuels” especially ultra-low sulphur diesel (ULSD) in favour of which powerful lobbies have launched a concerted campaign, with no less than the chief minister of Delhi and the union minister of petroleum and natural gas throwing their weight behind it.

This article looks at the merits of these and other potential fuels, and also examines the various related issues which should have been, but have not been, properly addressed. Important questions have also risen regarding the role of relevant ministries and regulatory authorities at the central and state levels, as well as the now familiar issue of the role of the judiciary in an activist mode, especially in relation to the roles of the legislature and the executive. The article also examines these and other wider implications of the Supreme Court’s orders and the manner in which they were issued and are being carried out.

It must be stressed that this is not an issue confined to Delhi. Citizens elsewhere in the country are doubtless going to confront the same issue in the very near future, going by the experience of previous Supreme Court decisions on related issues such as banning of public transport vehicles older than 15 years, mandatory use of lead-free petrol, enforcement of Euro-II vehicular emission norms and so on. In all these cases, the Supreme Court had first passed orders for Delhi and, in anticipation of similar orders being passed elsewhere either suo moto or in pursuit of sequential public interest litigation, other metropolitan cities quickly followed suit. Clearly, the Supreme Court’s orders for Delhi would have an all-India impact, both directly and indirectly.


Natural gas, like coal and oil, is a fossil fuel formed from plant and animal matter that has decayed over centuries. While natural gas has been known to humanity for many thousand years due to spontaneous fires generated by it, it first found public utility in London towards the end of the 19th century when it was used to light street lamps.

Compressed natural gas (CNG) is the most common fuel used in vehicles while liquified natural gas (LNG), which is stored under such low temperatures that the gas liquifies, is often preferred as an alternative to diesel especially in heavy long-distance trucks because of its high energy content and the comparatively less space required to carry the liquid. Today, natural gas powers over one million vehicles around the world. It is also used in engines of boats and trains, as well as for domestic heating, such as in over half the homes in the USA. Clearly, natural gas has emerged as a reliable and increasingly popular non-petroleum or “alternative fuel.”

One of the major reasons for this is the recognition of its environmental and other benefits. Natural gas is composed mostly of methane. Though methane is itself a harmful greenhouse gas (i e, one that adds to carbon dioxide in the atmosphere leading to the greenhouse effect or global warming), it is a relatively clean-burning fuel producing, on combustion, less carbon dioxide and harmful ozone-forming hydrocarbons than petroleum-based fuels. Dedicated natural gas engines emit about 90 per cent less carbon monoxide, 85 per cent less ozone-forming hydrocarbons and virtually no particulates, as compared to petrol or diesel-fuelled vehicles.

Additionally, unlike liquid fuel vehicles, dedicated natural gas vehicles emit no evaporative emissions from the heated engine or emissions during fueling, which can account for close to 40 per cent of hydrocarbon emissions in petroleum-based vehicles. Natural gas is also among the safest fuels on the road today. While diesel is inherently safer than petrol, natural gas being lighter than air dissipates into the atmosphere if a leak occurs. Further, it is stored in overground tanks, eliminating problems of leakages in underground storage tanks.

Importantly, if administered prices or selective subsidies are not involved, natural gas is 30 to 50 per cent cheaper than petrol and considerably cheaper than diesel, the comparative cost depending on the sulphur content of the diesel in which the less the sulphur percentage the greater is the cost. It is for these reasons that natural gas vehicles form such a large part of programmes to promote environment-friendly vehicles in numerous countries the world over, in efforts to counter the growing menace of vehicular pollution.

The problem of course is that it is not fuels that should be compared by the performance of engines and vehicles using them.


And this is exactly where the debate over CNG starts heating up. Proponents ranging from bus operators to the Delhi government’s transport minister Parvez Hashmi, the union petroleum minister Ram Naik and a host of experts from the redoubtable Tata Energy Research Institute (TERI) have been aggressively arguing the case for ultra low-sulphur diesel (ULSD) as being equally if not more environment friendly. Results of this examination should be interesting since the Bhure Lal committee comprises, besides the secretaries of the ministries of petroleum and energy, the high-profile environmentalist Anil Agarwal, known to be an ardent champion of CNG and who heads the the well-known NGO, Centre for Science & Environment (CSE), which has denounced TERI’s claims regarding ULSD as being misinformed and deliberately misleading.

Proponents of ULSD argue that the case for CNG being a “clean fuel” has been exaggerated, and especially that comparisons with so-called “dirty diesel” (such as used in India normally with sulphur content more than 500 ppm or parts per million) are unfair, whereas CNG would compare unfavourably with ULSD. Added to this is the argument that comparisons between CNG and ULSD are mostly based on emissions from engines running on special test beds, that is under laboratory conditions, whereas a better comparison would be based on tests under simulated road conditions in what is known as a chassis dynamometer test in which the engine is mounted on a real chassis and is subjected to tests simulating actual road conditions including stops, starts, cruises, crawls such as during heavy traffic. (Incidentally, it is believed that no institution in India is equipped to conduct such tests!) During the course of this high-powered campaign, some TV channels in India have also shown figures and charts purportedly showing that CNG actually comes off worse than ULSD in terms of emissions under simulated or actual road conditions. It is also claimed that low-sulphur diesel is also more economical than CNG.

Ironically, most of these above claims are based on the famous Hillsborough Tests run by London Transport on a single double decker bus running on a CNG-fuelled engine whereas the data available in India till now is based on experience of over five years in Mumbai and Delhi, with 20 BEST buses in the former having covered more than two million km and over 200 DTC buses in Delhi having covered over nine million km. These data show that, even compared to “dirty diesel,” fuel cost per km is Rs 4.07 for CNG compared to Rs 4.86 for diesel in Delhi, and Rs 6.41 and Rs 6.46 respectively for Mumbai. These figures show clearly that CNG is at least as economical as “dirty diesel” and these costs would be even more favourable if more expensive ULSD were to be used.

As for emissions from CNG and diesel, it is surmised that the figures bandied about on TV have been drawn from a particular Australian study which itself has been superseded by a later study from the same country. In any case, data from the USA, which has the largest body of evidence of operating CNG buses, show a clear and marked reduction of emissions in CNG buses as compared to diesel. (See the figure below from the US Environmental Protection Agency.)

It is understandable that some interest groups would like to push for diesel (ULSD being preferable to higher-sulphur diesel as it would be accepted by green lobbies) as it would require small additional investment on part of vehicle manufacturers, transport operators and fuel dispensing stations. On the other hand, ULSD would call for huge investments on part of oil and fuel refining companies, in India mostly by the state, thus thrusting the burden of costs on others’ shoulders. CNG, however, would call for additional investments by all these groups with the state’s investments being mostly in filling stations. It does not take a genius to figure out which interests are at work in pushing for ULSD!

There is one crucial aspect regarding the use of CNG that needs to be pondered over. At present there are only 68 CNG stations in Delhi, of which 45 are auxillary stations, i e they do not have boosters. Even with the present load, there are huge lines of vehicles waiting to be filled outside every station. Moreover, the present total installed capacity is to the tune of 1.8 lakh kg. It is estimated that the present demand is of one lakh kg, for 2000 buses. Thus the total capacity can at best cater to 3600 buses. If total conversion to CNG takes place we will have upward of 12,000 buses on the road. It is a moot point whether the infrastructure to service the lot, both in terms of filling stations and the installed capacity, can be got ready in time.


While the balance of the evidence at present appears to be in favour of CNG, this does not mean that the Supreme Court or the Bhure Lal committee assisting it arrived at the correct decision in ordering that Delhi switch over completely to CNG. In fact this has been a grave error in that emissions should have been made the sole criterion and yardstick rather than the type of fuel used. For instance, CNG-fuelled vehicles may today give the best emission figures but some better fuel-engine technology may give even better results tomorrow. Should citizens of Delhi or elsewhere be denied the opportunity to avail of this better option because the court had earlier ruled in favour of one particular option? Indeed, such a decision compelling an entire city’s (or tomorrow an entire country’s) fleet to use only one technology would actively prevent innovation and emergence of newer and better technologies.

In the USA two federal laws — the 1990 Clean Air Act (CAA) and the Energy Policy Act of 1992 (EPACT) — require certain fleets to operate on alternatives to petroleum fuels. The CAA requires individual states to implement clean-fuel fleet programmes and the EPACT requires the department of energy to implement an alternative-fuel fleet programme. The law requires that 10 per cent of all state and 30 per cent of all fuel-provider new vehicle purchases should be alternative fuel vehicles. The requirements increase each year, and were in 1999 extended to municipal and private fleets. By 2006, 75 per cent of all municipal and private fuel providers and 70 per cent of all municipal and private new vehicle purchases must be alternative fuel vehicles. As per these laws, alternative fuels could be CNG/LNG, ethanol, propane, various bio-fuels or vehicles could be powered by fuel-cells, batteries, etc, so long as they all conformed to common emission standards prescribed by the federal EPA and by respective state governments.

At present, the state of California has the USA’s most stringent emission standards, being even stricter than the federal standards. These emission standards have been prescribed for low-emission vehicles (LEV), ultra-low emission vehicles (ULEV), super ultra-low emission vehicles (SULEV) or zero emission vehicles (ZEV), the aim being to bring all vehicles at least to ULEV levels by 2007-2010. The state offers subsidies for new purchases of such vehicles or conversions of older vehicles to these standards, provided that the operating fleet or manufacturing company attains prescribed average emission standards for the entire fleet, leaving to the individual fleet the relative proportion of LEV, ULEV, SULEV or ZEV that it acquires or manufactures.

Once again, as we see, the aim and the criterion used to monitor progress towards it is not the fuel used or the type of vehicle but the level of emission set as the standard to be achieved within a stipulated time frame. The other noteworthy feature of the US system is that the process has been legislated, with clear executive and monitoring roles for the environment and energy/fuel departments or ministries.


In India, however, in coming down on the side of a single fuel (CNG) rather than specifying desirable emissions standards to be achieved irrespective of the engine technology or type of fuel used, the Supreme Court’s order and the advice given it by the Bhure Lal committee has done a disservice not only to the cause of the environment but also to the balance between the different arms of the state in a democracy. Unfortunately, such errors and flaws are inherent dangers in a judicial process where the court is called upon, and agrees to, not only adjudicate but pass detailed orders on matters involving a few issues of law and calling for wide-ranging expertise far beyond that which can be called upon by the judiciary to assist it in any single case. Can the judiciary be expected to decide, and should it attempt to so decide, as to which fuel is the most environmental friendly, or whether large dams are inherently anti-people? And can the judiciary expect to monitor and ensure compliance with its orders, however well-intentioned, if so many complex issues are interwoven with the functions and roles of so many departments and agencies at centre and in the states?

Even more unfortunately, this situation has been largely brought about by the continuing and worsening failure of the legislature and the executive to frame and implement proper laws and suitable enforcement, regulatory and monitoring mechanisms, besides enabling infrastructure, to tackle issues which, in the absence of these, affect the public interest and attract the attention of the judiciary which then tries to itself somehow undertake these tasks. Perhaps even now it is not too late for the Supreme Court to call upon the union government, especially its concerned ministries of petroleum, energy, environment and surface transport, with the assistance and cooperation of the state governments, to draw up time-scaled emission standards, fuel standards and vehicle technology standards as well as suitable action plans as regards achieving and maintaining fuel quality, infrastructure for fuel distribution and acquisition of vehicle technology, all aimed at ensuring high air quality and quality of life for Indian citizens.