Caught in a jam

  • 30/01/2002

Caught in a jam TWO-WHEELERS are Asia"s biggest challenge with most countries in the region being deluged with pollution from the huge number of them. Even where countries have tried, and tried hard to clean up their act, the pollution nightmare is not ending. Countries like India and Taiwan have armed themselves with the strictest emission standards anywhere in the world. Yet, neither is able to slay the dragon. The two countries have improved emission standards of two-wheelers to claim, and rightly so, that they have the tightest standards in the world. But pollution continues unabated. Which then is the way ahead?

In India, emission norms were first imposed in 1991. Since then public pressure has ensured that the auto industry improves its performance and the emission norms get harsher. The India 2000 emission norms are in fact quite stringent. Emission levels have been reduced by as much as 85 per cent over the past decade (see graph: Tough deal). Yet, the two and three-wheeled menace pollutes with just as much freedom. Compare the norms in place today and one realises: a new two-wheeler and a car today emit nearly the same lethal dose of pollutants. A three-wheeler is twice as bad. And in 2005, when even stricter norms are in place, the situation promises to be as dismal. A new two-wheeler will still emit more than a car would be allowed to in Europe and the three-wheeler will remain a killer (see table: Status quo).

Taiwan and other nations, with their emission norms in place, face the same dilemma. Asian countries, which do not have emission norms in place, on the other hand, are in deeper trouble. They do not have a single line of defence against the marauding army of dragons. Ironically, all countries know that the only way to beat these gargoyles is to aim for their heart - the engines that drive them. The problem is the two-stroke engines, which are inherently polluting and have little life ahead.

Death in two strokes
The main offender, the two-stroke engine, powers most of the vehicles on road. Their alternative, a more advanced two-wheeler technology of the four-stroke engines needs time to completely replace these vehicles. Both two-stroke and four-stroke engines function similarly: take in fuel, mix it with air, compress the mixture, burn it to get mechanical energy and belch out the exhaust. The difference is, in the two-stroke engine each such cycle is repeated faster than in a four-stroke. As a result the two-stroke engine gives more power. The scooters and motorcycles fitted with these engines are also cheaper. They are exactly what mothers do not like their kids to speed around on. But the real problem lies in their emissions. The simple design of this carburettor technology allows nearly one fourth of the fresh fuel charge to go out unburnt along with the exhaust causing very high hydrocarbon emissions. Over time, the two-stroke technology has improved but what"s been done to improve the engine is nothing more than mere tinkering, and tinkering does not help. The two-stroke technology has been pushed so far that it has been driven to a dead end. The pollution continues unabated. In fact, with people continuing to ply the old vehicles and the new ones being added (though in lesser numbers) each day there seems to be no easy way out of the impasse. Quick solutions
Some Asian governments have tried to chain the polluting dragons using different ploys. But in continuing with the same set of engines, their options remain limited. The most radical of these options and perhaps the most stringent one is to impose an outright ban on two-stroke engines and favour four-stroke technology. Nepal has done exactly that. "Indian exporters now sell four-stroke scooters which are also affordable," says Bhushan Tuladhar, executive director, Clean Energy Nepal. Taiwan too promises to stop production by 2004. "Taiwan Environment Protection Agency and two-wheeler manufacturers have an understanding to stop the production of two-stroke two-wheelers by January 2004." Informs, Jet P H Shu, deputy general director, Industry Technology Research Institute, Taiwan.

The other way out of the mess is to not impose a complete ban but put up stricter emission norms that push the technology out. In India even though consumer preferences are changing the market towards four-stroke, a huge fleet of two-stroke two-wheelers remains. Strict emission norms have also helped. In 2001, four-stroke comprised 65 per cent of the annual sales, even the rest 35 per cent of two- stroke engines on the road makes for a large number in absolute terms.

Thailand plans to toughen norms also. "Most manufacturers are changing over to four-stroke motorcycles because some two-stroke motorcycles can"t clear the emission norms. By 2003 when tougher standards are in place, we"ll have only four-stroke motorcycles," says Janejob Suksod, chief of the automotive air pollution sub-division of the Thailand Pollution Control Department. But some experts assert that a complete ban is the only way out. If Bangkok had phased out two-stroke engines five years ago the particulate pollution would have been halved, says Jitendra Shah, environment engineer at the World Bank. "It"s a case of missed opportunity," bemoans Shah.

Conversion blues
Indian auto industry dislikes the idea of a complete ban. It avers that only emissions standards be declared and the options left open to the automakers. It asserts that it can wriggle its way out by innovating the two-stroke engine. But can it? The only way the industry can meet the current emission norms is by fitting an after-treatment device, or a catalytic converter on these machines. But do these catalytic converters provide the answer to pollution. Many experts think not (see graph: Catalytic effect). Catalytic converters used on two-stroke engines have a special problem. High emissions and high temperature reduces the life of the catalytic converters. There is no answer to it. Converters remain a yet unknown entity and their ability to muzzle the dragons, at best, a hope. Typical problems of two-stroke engines make it difficult for converters to perform at the optimum for long. They begin to age and efficiency reduces with usage.

How do these converters perform on road? Considering the amount of adulteration of fuels, inappropriate use of lubricants, and poor maintenance - a reality in countries such as India - the question becomes vital. The commuter is left to drive in the dark, as little research exists to answer such queries? It gets murkier in fact. The catalytic converter"s efficiency varies with changes in the mixing of air and fuel during combustion, which usually occur in these engines. Data from Engelhard Asia Pacific Ltd, manufacturers of catalytic converters, show that with varying air-fuel mixture emissions varies drastically - carbon monoxide emissions can vary by more than 90 per cent. Indian manufacturers certify that their catalytic converters function up till 30,000 kms - roughly five years on an average in our cities. But compare this to Taiwan, which certifies its converters for only 15,000 kms.

Taiwan finds it easier to deal with the problem. Being a consumerist society, the scooters and other two-wheelers get discarded much quicker there than they do in India. Which means that the vehicle goes off the road before its performance deteriorates. But Taiwan government is also very proactive. It encourages users to scrap the old vehicles by giving monetary incentive. Otherwise, users have to pay for repairs to ensure the vehicles pass the tests conducted on-road." And better still, Taiwan holds manufacturers responsible for emissions from vehicles even after they have been sold and are on road.

In India, there were efforts to hold industry responsible for their emissions but government action has been weak. Strong public pressure pushed the industry to agree to voluntary emissions warranty but the government still dithers from giving it legal teeth (see box: Total recall).

There is also a problem with the vehicles on the roads. Very few countries have policies to junk polluting old scooters. Monitoring emissions from on-road vehicles is ineffectual. Governments have done little to improve the system. In most Asian countries emission checks are limited to carbon monoxide and in some cases hydrocarbons and smoke. Testing of the pollutants emitted in the exhaust is essential. Kathmandu"s experience proves this. When tested for only idling carbon monoxide most two-wheelers passed tests in Nepal"s capital but more failed when also tested for hydrocarbons.

The industry and the government have tried to undo the knotty situation but the noose around the public has only tightened with time. The tough emission norms have come up a cropper. Is it time for all concerned to realise that doubtful technology like catalytic converter may not be the real solution but only a postponement of a malady? Is it time to do a complete overhaul of the two and three-wheeler industry and say take a quantum leap, in thought and in technical know-how?

Status quo
Even under new norms, two and three-wheelers
will be more polluting than cars
Type of vehicle India 2000 emission norms
for carbon monoxide
(in grammes/km)
Proposed carbon
monoxide norms
(in grammes/km)
  1.00 (Euro IV)
  1.50 (Proposed by SIAM)
  2.25 (Proposed by SIAM)

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