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The Big Choke
How does motorized transport contribute to pollution? What makes it worse? Is it simply a question of choosing the right fuel? How can we make City air breathable again? What effective short-term measures can show results in weeks and months instead of years? These are some of the questions that need to be an I hope are addressed below, with the belief that an informed citizenry is the most effective agent of change for the better. Motorized transport is essentially based on the internal combustion engine: the engine burns a mixture of air and fuel to produce energy that powers the vehicle, be it a small scooter or a 10-tonne truck. What pollutants are released during this combustion, and in what quantities, is affected by more than a dozen factors the kind of fuel, whether petrol, diesel, LPG or CNG, is just one of them. It is important to understand this because the mass media, in their compulsion to present a good storyı, have simplified the transport/pollution issue to such an extent that many now perceive it only as a choice between CNG, LPG, petrol or diesel used in the plague of PMVs. To take an extreme example, consider the zero emissionsı cars that run on electricity, one of the cleanest fuels available. The cars are powered by batteries: there is no fuel to be burnt. So what prevents such vehicles from being the first choice in the battle against pollution? For one, battery-operated vehicles have a limited range and carrying capacity: the solar-powered vans usually can carry no more than 8 passengers. Clearly, such vehicles, at least at present, are not an option for mass transit, no matter how clean they are, though they do have a well-defined niche and ought to be a part of the solution. The practical feasibility of an option and its cost are important determinants of its suitability for adoption. Compressed natural gas is known to be a clean fuel, far cleaner than dieselbut which diesel? It is unfair to compare CNG with the so-called dirtyı diesel, which contains as much as 0.5% sulphur. A fairer comparison will be with ULSD, or ultra-low-sulphur diesel, which, at 0.005% sulphur, is a hundred times cleaner. Many European countries, particularly those in Northern and Western Europe, are already committed to ULSD. City diesel, as ULSD is known in Europe, as introduced in Finland and Sweden in 1993; since then, it has captured nearly 100% of the Scandinavian diesel market. By 2001/02, the UK market is also expected to follow suit. ULSD is not currently produced or available in New Zealand, do we have the technical capability to produce it? Don't know. The best that is on offer here seems to be low sulphur (0.05%) available only in Christchurch (which has worse air-pollution even than Auckland). This situation is third-rate, perhpas reflecting the opinion global corportations and our own government has of city dwellers. Though CNG is particularly suited to small commercial vehicles such as taxis, seldom used for long-haul travel or to carry heavy payloads, for such heavy-duty vehicles as buses, the choice between CNG and clean diesel is far from clear, with each lobby citing experimental data to support its claims. Therefore, it is essential to test any new technology to find out how suitable it is to local conditions. The technical feasibility of improved heavy-duty vehicles and fuel technology and the associated costs will have to be definitively established before making a final recommendation either in favour or against any particular technologyfuel combination. Nowhere in the world has any agency responsible for meeting travel needs on a large scale opted to convert its entire fleet to run on CNG. An overloaded bus negotiating typical city traffic can fall far short of its performance in a laboratory. Congestion, overloading, poor maintenance, adulterated fuel, poor roads realities that cannot be wished away all take their toll; solutions that appear simple and effective on paper turn out to be complicated and ineffective in practice. Trials commissioned by the London Transport Board provide a concrete example. The tests mimicked a typical bus journey on city roads: a mix of fast and slow stretches, low average speeds, frequent stops at traffic intersections and to pick up and discharge passengers, extended idling times, and so on. Buses running on CNG and fitted with an oxidizing catalystwere compared with those running on ULSD and fitted with a continuously-regenerating particulate trap in terms of the amount of different pollutants they emitted for every kilometre of travel. Clean diesel emitted less of every pollutant except nitrogen oxides. Trials conducted by New York City Transit showed similar results. In particular, carbonyl emissions were practically eliminated (reductions of more than 99%). Carbonyls include aldehydes such as formaldehyde and acetaldehyde, which are categorized by USEPA (United States Environment Protection Agency) as hazardous air pollutantsı. Also, emissions of PAH (polynuclear aromatic hydrocarbons) were reduced by as much as 80%. How expensive will it be to operate a fleet of buses running on a single fuel? Capital costs include the costs of new buses or retrofitting old ones, and the cost of infrastructure (filling stations, pipelines, etc.) can be substantial. Even after they are operational, CNG buses will continue to run up higher fuel bills which could strangely enough be extra for CNG. (The fuels costs are economic costs, that is, excluding taxes and duties.) Who will pay these additional costs? Obviously, the consumer. How long will it take to put 1000 CNG-operated buses on Auckland's or Christchurch's roads even if we have the money? We must realize that the number (1000) is as important as the fuel (CNG) because we cannot hope to achieve the intended result, namely cleaner air, if the figure drops far below that number. And as we wait, an extreme example of the human cost (not to mention all other life) is that more than 2% people in the prime of their life (15 to 45 years) will continue to die prematurely in Delhi every year of breathing or heart-related disorders brought on because of polluted air. The city of Perth in Australia commissioned an expert group comprising members from gas authorities, transport and environment departments, and an environmental economist for advice on the best fuel for Perthıs buses in the long termı. The group concluded that on all three grounds environmental, operational, and economic low-sulphur diesel was the fuel of choice. Cycling and walking, the so-called non-motorized transportı, are the cleanest modes of transport, yet account for an insignificatnt proportion of all journeys to work in Auckland, and even in Christchurch this is the case. Its clean to walk and cycle, yet little is done to help people who do by way of introducing separate dedicated bicycle lanes. Such lanes not only increase the carrying capacity of roads by providing a separate stream for the slow-moving non-motorized traffic but also make journeys safer for pedestrians and cyclists. IN New Zealand cities, the walker and cyclist is viewed as a nuisance by drivers and authorities, instead of a saviour. The issue, therefore, is not so much air pollution as poor public transport: a bus spewing smoke and soot appears to be a major culprit but if all of those 40-odd passengers in the bus were to travel in cars or ride motorcycles, will the extent of pollution be any less? Polluted air is a symptom, a symptom of the absence of a coherent, integrated policy for transport. Attempts to control air pollution without improving the way transport is managed in cities is like dipping a thermometer in a bucket of ice to escape summer heat. Choosing the right combination of automobile technology and fuel, of course, is a very important part of any strategy to reduce the ill effects of air pollution, but it is not the only solution. Are we focusing on any of the others? What, then, should we do? The logic is straightforward: to reduce pollution, (1) reduce the number of kilometres travelled and (2) reduce the amount of pollution per kilometre of travel. The first, which focuses on efficient management of traffic, represents the strategic approach and the second, which focuses on vehicles and fuels, represents the technical approach. The strategic approach, for most part, offers quick solutions the results of which will be apparent within months whereas the technical approach covers solutions the benefits of which will be apparent only over years. In terms of costs also, the strategic approach is generally cheaper than the technical approachit is also the least controversial. The strategic approach: reducing the number of kilometres travelled Reducing the number of kilometres travelled consists of (1) reducing the number of vehicles on the road and (2) reducing the number of kilometres travelled by each vehicle. To reduce the number of vehicles on the road, it is essential to look into why people travel and what influences their mode of travel: walking, cycling, taking a public bus, a car, riding a motorcycle or whatever. Cost, comfort, reliability, time spent in travelling, the distance to be travelled, the purpose of travelall have a bearing on the choice. PMVs account for the largest share in the total number of registered vehicles in New Zealand. If their owners are to be persuaded to leave them at home and use public transport instead, the alternative has to be distinctly superior: reliable, comfortable, fast, cheap, and accessible. At the same time, travel in personal vehicles needs to reflect its true costs in terms of space and infrastructure, which can be recovered through stiff parking fees, higher charges for the use of roads, restricted entry at peak times, and so on. According priority to buses at intersections and grade separationı, that is assigning different lanes to slow- and fast-moving vehicles and to motorized and non-motorized vehicles (bicycles for instance), are just two of the examples to promote more efficient and equitable use of road space. Of the many innovative features introduced in Curitiba, in Brazil, is raised platforms for boarding or alighting from buses, which makes the process not only quicker but also easier. Buses make up less than 1% of the total number of motorized vehicles in New Zealand but meet five times that percentage of the total travel needs. Priority to buses at traffic intersections can cut down travel time by as much as 25%. Dedicated bus lanes are estimated to increase the carrying capacity of buses by more than 50%. Long-term strategic measures to reduce the number of kilometres travelled by each vehicle include better land-use planning, decentralization, and encouraging people to admit their children to nearby schools. The technical approach: reducing the amount of pollution per kilometre of travel Reducing the amount of pollution per kilometre of travel consists of such measures as (1) using cleaner fuels, (2) burning fuels more efficiently, (3) trapping the pollutants before they escape into the atmosphere, (4) keeping engines well-tuned by regular and effective inspection and maintenance, and (5) ensuring smoother driving, avoiding the gridlock that characterises Auckland's roads and motorways ten times a week. The cleaner fuels include CNG, LPG and ULSD seems obvious, but is rarely discussed, especially the move to ULSD whereas burning them more efficiently is covered by such standards as the easily obtained Euro norms, which specify upper limits to the quantity of pollutant emitted per kilometre or, in the case of heavy-duty vehicles, per kilowatt-hour. For a bus to conform to Euro 2 norms, for instance, it cannot emit more than 0.15 grams of particulate matter per kilowatt-hour (0.11 gram per brake horsepower-hour). Trapping the pollutants or converting them into non-polluting substances is the approach used in catalytic converters, mostly used in petrol-powered vehicles, and after-treatmentı devices used in conjunction with ULSD, a particularly effective combination. Keeping engines well-tuned through proper I&M (inspection and maintenance) itself can cut down pollution given the fact that for several years to come, a significant percentage of the vehicles on Auckland roads will be of pre-1995 vintage when the norms for European produced vehicle's emissions were far less stringent and worse, to this day Japanese manufactured PMVs have their pollution reduction equipment illegalised in New Zealand, where it is stripped out. Smoother driving allows engines to run for longer periods at cruising speeds, which ensures more efficient combustion and thus reduces pollution - gridlock is not just an inconvenience, its a major killer of city-life. Table 2 Improving public transport: here and now Technical measures: Continue to convert old diesel buses to CNG but provide for adequate field-testing. Augment the fleet of buses as a matter of priority and permit Euro I or later ULSD buses equipped with particulate traps to ply so that the fleet is augmented quickly enough. It may be necessary to import ULSD for New Zealand city buses until such time as our refineries can start producing it indigenously. In any case, neither the technical superiority nor logistical or economic feasibility of CNG/LPG is proven beyond doubt so far. Set emission norms for service providers and insist on compliance instead of the choice of fuel. Implement the short-term strategic measures within the next 6 months. Strategic measures. Increase the speed of introduction of bus-only lanes. At traffic signals, give priority to buses. Identify large parking lots for two-wheelers and cars and introduce park-and-ride schemes with a single ticket inclusive of both parking charges and bus tickets. Restrict new taxis only to those that run on CNG and meet the Euro 2 norms. Identify busy corridors and provide a shuttle service along the corridors using shared taxis and minibuses. Offer financial incentives to the private sector to buy buses that use cleaner fuels and improved technologies. Set up a regulatory body to draw up and allocate routes, fix bus fares, and monitor the overall transport service to safeguard the interests of the travelling public. Provide government incentives to employers to make it financially attractive for employees to move house close to the place of work, and do the same for school zoning regulations to make living near school essential to attendence at it. Conclusion Motorized transport, particularly the use of PMVs continues to pollute. Clean fuels can be a part of the solution only if there are enough buses on the road to prevent more people from opting for personal transport. What is more pragmatic is to augment the bus fleet and allow it to run on any clean fuel, be it CNG or ULSD, and focus on devising and implementing strategies that can show results quickly. Buses, no matter how clean, cannot do the job alone and cannot do it soon enough while hundreds of thousands choose to travel by cars, motorcycles, scooters, etc. It is up to the government and the entire citizenry of Auckland and other major cities in New Zealand to join hands to make public transport a model of efficient, equitable, and attractive city transport that integrates strategic and technical measures covering the choice of fuel and vehicle technologies conforming to progressively stringent emission norms along with effective traffic management. Given the will, or more to the point, the money from local and central government, transport in cities could be radically improved - this is a health issue, not one that is to be left in the hands of commerce which has demonstrated patent dis-regard for health and well-being..
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