Short-term activity often promotes incremental improvement in fuel efficiency and vehicle emissions controls while long-term goals include migrating transportation from fossil-based energy to other alternatives such as renewable energy and use of other renewable resources. The entire life cycle of transport systems is subject to sustainability measurement and optimization.
Sustainable transport systems make a positive contribution to the environmental, social and economic sustainability of the communities they serve. Transport systems exist to provide social and economic connections, and people quickly take up the opportunities offered by increased mobility, with poor households benefiting greatly from low carbon transport options. The advantages of increased mobility need to be weighed against the environmental, social and economic costs that transport systems pose.
Transport systems have significant impacts on the environment, accounting for between 20% and 25% of world energy consumption and carbon dioxide emissions. The majority of the emissions, almost 97%, came from direct burning of fossil fuels. Greenhouse gas emissions from transport are increasing at a faster rate than any other energy using sector. Road transport is also a major contributor to local air pollution and smog.
The United Nations Environment Programme (UNEP) estimates that each year 2.4 million premature deaths from outdoor air pollution could be avoided. Particularly hazardous for health are emissions of black carbon, a component of particulate matter, which is a known cause of respiratory and carcinogenic diseases and a significant contributor to global climate change. The links between greenhouse gas emissions and particulate matter make low carbon transport an increasingly sustainable investment at local level—both by reducing emission levels and thus mitigating climate change; and by improving public health through better air quality.
The social costs of transport include road crashes, air pollution, physical inactivity, time taken away from the family while commuting and vulnerability to fuel price increases. Many of these negative impacts fall disproportionately on those social groups who are also least likely to own and drive cars. Traffic congestion imposes economic costs by wasting people's time and by slowing the delivery of goods and services.
Traditional transport planning aims to improve mobility, especially for vehicles, and may fail to adequately consider wider impacts. But the real purpose of transport is access – to work, education, goods and services, friends and family – and there are proven techniques to improve access while simultaneously reducing environmental and social impacts, and managing traffic congestion. Communities which are successfully improving the sustainability of their transport networks are doing so as part of a wider programme of creating more vibrant, livable, sustainable cities.
Definition
The term sustainable transport came into use as a logical follow-on from sustainable development, and is used to describe modes of transport, and systems of transport planning, which are consistent with wider concerns of sustainability. There are many definitions of the sustainable transport, and of the related terms sustainable transportation and sustainable mobility. One such definition, from the European Union Council of Ministers of Transport, defines a sustainable transportation system as one that:
Allows the basic access and development needs of individuals, companies and society to be met safely and in a manner consistent with human and ecosystem health, and promotes equity within and between successive generations.
Is affordable, operates fairly and efficiently, offers a choice of transport mode, and supports a competitive economy, as well as balanced regional development.
Limits emissions and waste within the planet’s ability to absorb them, uses renewable resources at or below their rates of generation, and uses non-renewable resources at or below the rates of development of renewable substitutes, while minimizing the impact on the use of land and the generation of noise.
Sustainability extends beyond just the operating efficiency and emissions. A life-cycle assessment involves production, use and post-use considerations. A cradle-to-cradle design is more important than a focus on a single factor such as energy efficiency.
Causes and mechanisms of action
Some scientists such as Winfried Wolf, Hermann Knoflacher, Heiner Monheim or Frederic Vester have analyzed the mechanisms for these developments and u. a. the following theses are drawn up:
One-sided Lobbying
Unilateral lobbying for the MIV in transport policy and planning has been instrumental in promoting MIV at the expense of other modes of transport from the outset.
Although there were already separate sidewalks in different cities in ancient times and for example in Berlin since the first half of the 19th century large sidewalks were created , it was common in many places until the 1920s and legitimate that all road users shared the entire road space. Not only did pedestrians walk the streets, they also stayed and used the road as a habitat. With the advent of car traffic, more and more separate areas were created for the different types of traffic, which sometimes caused violent protests in the pedestrians: "From where does the automaker have the right to dominate the street, as he praises himself, which by no means belongs to him, but to the entire population, to hinder them at every turn and to dictate to them a behavior that they only pursue on their own, private Due to demand? "
Although motorists were then a small minority of road users, pedestrians now had to walk on the side of the road and were only allowed to cross the road, and only in a reasonable hurry and only if they did not hinder a driver. Markus Schmidt calls this "built-in right of way" the key to the following massive increase in MIV.
In the 1930s, the first car-friendly urban redevelopments were implemented in Germany through road breaks and demolitions for parking lots as well as increased regulation of all traffic in favor of the cars. For example, it is assumed that travel times for pedestrians have doubled since the beginning of the introduction of more and more traffic lights in the 1960s.
The following example from Linz shows how, despite promises by politicians to take action against the increase in MIV, MIV is still favored in allocating resources: although transport policy had planned to reduce the MIV share to 43% by 2010 (As of 2001: 61%) and to increase the share of cycling from 6% to 14%, between 1995 and 2010 about 62% of total transport expenditure will be spent on promoting motor vehicle traffic, but less than 1% on cycling.
A study commissioned by the US Senate in 1974 proves a conspiracy against rail-bound traffic: over more than three decades, rail-based electric vehicles that had functioned well in countless large US cities were bought by a group of oil and automobile companies. decommissioned and replaced by bus companies. A devastating deterioration of the air and quality of life was u. a. the episode.
Law of Time Constancy
The faster the locomotion is possible, the longer the paths covered become: whether a route is covered, decides only the duration, not the distance. Speed increases therefore result in no time gain, but only a spatial expansion.
The growing expansion of the road network, but also the construction of high-speed railway lines are major causes for the thinning of the infrastructure and the associated increase in the distance traveled.
Supply Creates Demand
The expansion of the road system causes an increase in traffic.
The closing of motorway gaps, for example, repeatedly caused enormous growth rates in road transit traffic, as well as the expansion of existing roads. In an UPI study, bypasses are referred to as " in most cases counterproductive sham solutions " in which " the overall balance is often not positive, taking into account the recharge caused by the bypass. " Noise pollution, pollutant emissions and number and severity of accidents increase as a result of the Car traffic and travel speeds.
For example, the Vienna Südost-Tangente was built as a relief highway for a 20,000 motor vehicle per day on the inner-city road; In the first year after opening, traffic there was reduced to 7,000 vehicles per day, but ten years later it had risen again to 24,000, and 100,000 cars per day had been counted on the relief highway.
According to an UPI study, today " the number of cars is expanding about nine times faster than the road network. Even if in the future nine times as much and nine times as fast new roads would be built as before, the traffic jams and congestion of the road network could be kept on the current level! "
Conversely, a reduction in the road network usually leads to a decline in traffic. When, for example, the Donnersberg Bridge in Munich was redeveloped in March 1993, people were afraid of "permanent congestion without end", because the bridge, with 150,000 cars a day, is one of the busiest overpasses in Europe. But the opposite was the case: Although the bridge could only be driven on two lanes for several months, the motor vehicle drivers usually made rapid progress. Census showed that daily 32,000 cars were less than usual on the road. Only 25,000 more cars were counted on the parallel routes, reducing the total traffic by 7,000 vehicles.
Lack of cost truth
When considering the overall economic and environmental costs of covers MIV - and truck traffic only a fraction of the costs associated with it; The public transport deficit is much lower than that of MIV and HGV traffic. This lack of cost truth leads according to the market economy laws to a disproportionate development of the MIV and truck traffic.
The construction and maintenance of transport routes creates so-called infrastructure costs (including internal costs or infrastructure costs); In addition, environmental costs, surface loads and accidents generate economic costs, which are referred to as external costs, and which, in contrast to internal costs, are generally borne not by the polluter but by the general public.
A comparison of the infrastructure costs for motor vehicle traffic with the revenue from vehicle and fuel tax in the Federal Republic of Germany in the period from 1960 to 1989 results, according to a UPI study a deficit of 106 billion DM, while the DB in the same period a deficit of about DM 30 billion (both excluding interest and principal payments for old debts).
The German Institute for Economic Research (DIW) assumes in a study from 1985 that " the maintenance costs for municipal and state roads amounting to 231 billion DM (151 West, 80 East) until the year 2010 is completely uncovered ".
A calculation of the external costs of motor vehicle traffic in the Federal Republic of Germany results for 1989 that the external costs about ten times as high as the internal costs (1996 according to the increased infrastructure costs 6.5 times as high;) if the external costs were also covered by the mineral oil tax in accordance with the 'polluter pays' principle, one liter of fuel would cost around € 3.50 (as of 1994, after the 2006 VPI development around € 4). The following table shows the annual and average external transport costs in the EU-17 Member States in 2000 (excluding congestion costs):
The external costs per passenger kilometer (pkm) are about one third for rail vehicles and about half of the external costs of passenger car transport for buses; With 226 euros per 1000 pkm, motorcycle traffic has by far the highest external costs due to its high accident costs. For freight transport, the external costs (per tonne-km) of road traffic are about 4 to 14 times greater than for railways. Overall, the annual external costs of MIV and truck transport are almost 20 times the external costs of public transport and rail freight transport.
In aviation, the high external costs are due to the high impact of high carbon dioxide emissions on climate change. For aircraft turbine fuel kerosene as well as for diesel fuels for inland shipping neither has oil - even VAT to be paid (see, eg kerosene tax).
Increasing inefficiency of traffic
Despite the high increase in traffic, human mobility needs are no longer met.
The combination of the causes listed in the preceding theses causes, in addition to the increase in traffic, at the same time, an increase in the transport routes, so that the overall efficiency substantially decreases with approximately constant benefit.
History
Most of the tools and concepts of sustainable transport were developed before the phrase was coined. Walking, the first mode of transport, is also the most sustainable. Public transport dates back at least as far as the invention of the public bus by Blaise Pascal in 1662. The first passenger tram began operation in 1807 and the first passenger rail service in 1825. Pedal bicycles date from the 1860s. These were the only personal transport choices available to most people in Western countries prior to World War II, and remain the only options for most people in the developing world. Freight was moved by human power, animal power or rail.
The post-war years brought increased wealth and a demand for much greater mobility for people and goods. The number of road vehicles in Britain increased fivefold between 1950 and 1979, with similar trends in other Western nations. Most affluent countries and cities invested heavily in bigger and better-designed roads and motorways, which were considered essential to underpin growth and prosperity. Transport planning became a branch of Urban Planning and identified induced demand as a pivotal change from "predict and provide" toward a sustainable approach incorporating land use planning and public transit. Public investment in transit, walking and cycling declined dramatically in the United States, Great Britain and Australia, although this did not occur to the same extent in Canada or mainland Europe.
Concerns about the sustainability of this approach became widespread during the 1973 oil crisis and the 1979 energy crisis. The high cost and limited availability of fuel led to a resurgence of interest in alternatives to single occupancy vehicle travel.
Transport innovations dating from this period include high-occupancy vehicle lanes, citywide carpool systems and transportation demand management. Singapore implemented congestion pricing in the late 1970s, and Curitiba began implementing its Bus Rapid Transit system in the early 1980s.
Relatively low and stable oil prices during the 1980s and 1990s led to significant increases in vehicle travel from 1980–2000, both directly because people chose to travel by car more often and for greater distances, and indirectly because cities developed tracts of suburban housing, distant from shops and from workplaces, now referred to as urban sprawl. Trends in freight logistics, including a movement from rail and coastal shipping to road freight and a requirement for just in time deliveries, meant that freight traffic grew faster than general vehicle traffic.
At the same time, the academic foundations of the "predict and provide" approach to transport were being questioned, notably by Peter Newman in a set of comparative studies of cities and their transport systems dating from the mid-1980s.
The British Government's White Paper on Transport marked a change in direction for transport planning in the UK. In the introduction to the White Paper, Prime Minister Tony Blair stated that
We recognise that we cannot simply build our way out of the problems we face. It would be environmentally irresponsible – and would not work.
A companion document to the White Paper called "Smarter Choices" researched the potential to scale up the small and scattered sustainable transport initiatives then occurring across Britain, and concluded that the comprehensive application of these techniques could reduce peak period car travel in urban areas by over 20%.
A similar study by the United States Federal Highway Administration, was also released in 2004 and also concluded that a more proactive approach to transportation demand was an important component of overall national transport strategy.
Environmental impact
Transport systems are major emitters of greenhouse gases, responsible for 23% of world energy-related GHG emissions in 2004, with about three quarters coming from road vehicles. Currently 95% of transport energy comes from petroleum. Energy is consumed in the manufacture as well as the use of vehicles, and is embodied in transport infrastructure including roads, bridges and railways.
The first historical attempts of evaluating the Life Cycle environmental impact of vehicle is due to Theodore Von Karman. After decades in which all the analysis has been focused on emending the Von Karman model, Dewulf and Van Langenhove have introduced an model based on the second law of thermodynamics and exergy analysis. Chester and Orwath, have developed a similar model based on the first law that accounts the necessary costs for the infrastructure.
The environmental impacts of transport can be reduced by reducing the weight of vehicles, sustainable styles of driving, reducing the friction of tires, encouraging electric and hybrid vehicles, improving the walking and cycling environment in cities, and by enhancing the role of public transport, especially electric rail.
Green vehicles are intended to have less environmental impact than equivalent standard vehicles, although when the environmental impact of a vehicle is assessed over the whole of its life cycle this may not be the case. Electric vehicle technology has the potential to reduce transport CO2 emissions, depending on the embodied energy of the vehicle and the source of the electricity. The primary sources of electricity currently used in most countries (coal, gas, oil) mean that until world electricity production changes substantially, private electric cars will result in the same or higher production of CO2 than petrol equivalent vehicles. The Online Electric Vehicle (OLEV), developed by the Korea Advanced Institute of Science and Technology (KAIST), is an electric vehicle that can be charged while stationary or driving, thus removing the need to stop at a charging station. The City of Gumi in South Korea runs a 24 km roundtrip along which the bus will receive 100 kW (136 horsepower) electricity at an 85% maximum power transmission efficiency rate while maintaining a 17 cm air gap between the underbody of the vehicle and the road surface. At that power, only a few sections of the road need embedded cables. Hybrid vehicles, which use an internal combustion engine combined with an electric engine to achieve better fuel efficiency than a regular combustion engine, are already common. Natural gas is also used as a transport fuel. Biofuels are a less common, and less promising, technology; Brazil met 17% of its transport fuel needs from bioethanol in 2007, but the OECD has warned that the success of biofuels in Brazil is due to specific local circumstances; internationally, biofuels are forecast to have little or no impact on greenhouse emissions, at significantly higher cost than energy efficiency measures.
In practice there is a sliding scale of green transport depending on the sustainability of the option. Green vehicles are more fuel-efficient, but only in comparison with standard vehicles, and they still contribute to traffic congestion and road crashes. Well-patronised public transport networks based on traditional diesel buses use less fuel per passenger than private vehicles, and are generally safer and use less road space than private vehicles. Green public transport vehicles including electric trains, trams and electric buses combine the advantages of green vehicles with those of sustainable transport choices. Other transport choices with very low environmental impact are cycling and other human-powered vehicles, and animal powered transport. The most common green transport choice, with the least environmental impact is walking.
Transport on rails boasts an excellent efficiency (see fuel efficiency in transportation).
Transport and social sustainability
Cities with overbuilt roadways have experienced unintended consequences, linked to radical drops in public transport, walking, and cycling. In many cases, streets became void of “life.” Stores, schools, government centers and libraries moved away from central cities, and residents who did not flee to the suburbs experienced a much reduced quality of public space and of public services. As schools were closed their mega-school replacements in outlying areas generated additional traffic; the number of cars on US roads between 7:15 and 8:15 a.m. increases 30% during the school year.
Yet another impact was an increase in sedentary lifestyles, causing and complicating a national epidemic of obesity, and accompanying dramatically increased health care costs.
Strategies for a Gentle Mobility
It has developed strategies for modifying transport development in favor of soft mobility and a better quality of life: a transport policy that promotes soft mobility, seeks to attract and promote soft mobility by means of measures and investment, while others are needed Transport (MIV, truck, air traffic) and through taxation (such as increasing the excise duty on internalisation of external costs (eco-tax), ecobonus system, parking management, inner-city toll) and restrictions (such as night-time driving ban, speed limits, Gateways) to reduce. At the same time, it must also change the distribution of space in public space in favor of soft mobility, such as traffic calming and road-building. Last but not least, such a transport policy must actively intervene in settlement policy, spatial and urban planning, in order to achieve high quality of life in settlement areas and short distances, and thus to prevent urban sprawl.
Cities
Cities are shaped by their transport systems. In The City in History, Lewis Mumford documented how the location and layout of cities was shaped around a walkable center, often located near a port or waterway, and with suburbs accessible by animal transport or, later, by rail or tram lines.
In 1939, the New York World's Fair included a model of an imagined city, built around a car-based transport system. In this "greater and better world of tomorrow", residential, commercial and industrial areas were separated, and skyscrapers loomed over a network of urban motorways. These ideas captured the popular imagination, and are credited with influencing city planning from the 1940s to the 1970s.
The popularity of the car in the post-war era led to major changes in the structure and function of cities. There was some opposition to these changes at the time. The writings of Jane Jacobs, in particular The Death and Life of Great American Cities provide a poignant reminder of what was lost in this transformation, and a record of community efforts to resist these changes. Lewis Mumford asked "is the city for cars or for people?" Donald Appleyard documented the consequences for communities of increasing car traffic in "The View from the Road" (1964) and in the UK, Mayer Hillman first published research into the impacts of traffic on child independent mobility in 1971. Despite these notes of caution, trends in car ownership, car use and fuel consumption continued steeply upward throughout the post-war period.
Mainstream transport planning in Europe has, by contrast, never been based on assumptions that the private car was the best or only solution for urban mobility. For example, the Dutch Transport Structure Scheme has since the 1970s required that demand for additional vehicle capacity only be met "if the contribution to societal welfare is positive", and since 1990 has included an explicit target to halve the rate of growth in vehicle traffic. Some cities outside Europe have also consistently linked transport to sustainability and to land-use planning, notably Curitiba, Brazil, Portland, Oregon and Vancouver, Canada.
There are major differences in transport energy consumption between cities; an average U.S. urban dweller uses 24 times more energy annually for private transport than a Chinese urban resident, and almost four times as much as a European urban dweller. These differences cannot be explained by wealth alone but are closely linked to the rates of walking, cycling, and public transport use and to enduring features of the city including urban density and urban design.
The cities and nations that have invested most heavily in car-based transport systems are now the least environmentally sustainable, as measured by per capita fossil fuel use. The social and economic sustainability of car-based transportation engineering has also been questioned. Within the United States, residents of sprawling cities make more frequent and longer car trips, while residents of traditional urban neighbourhoods make a similar number of trips, but travel shorter distances and walk, cycle and use transit more often. It has been calculated that New York residents save $19 billion each year simply by owning fewer cars and driving less than the average American. A less car intensive means of urban transport is carsharing, which is becoming popular in North America and Europe, and according to The Economist, carsharing can reduce car ownership at an estimated rate of one rental car replacing 15 owned vehicles. Car sharing has also begun in the developing world, where traffic and urban density is often worse than in developed countries. Companies like Zoom in India, eHi in China, and Carrot in Mexico, are bringing car-sharing to developing countries in an effort to reduce car-related pollution, ameliorate traffic, and expand the number of people who have access to cars.
The European Commission adopted the Action Plan on urban mobility on 2009-09-30 for sustainable urban mobility. The European Commission will conduct a review of the implementation of the Action Plan in the year 2012, and will assess the need for further action. In 2007, 72% of the European population lived in urban areas, which are key to growth and employment. Cities need efficient transport systems to support their economy and the welfare of their inhabitants. Around 85% of the EU’s GDP is generated in cities. Urban areas face today the challenge of making transport sustainable in environmental (CO2, air pollution, noise) and competitiveness (congestion) terms while at the same time addressing social concerns. These range from the need to respond to health problems and demographic trends, fostering economic and social cohesion to taking into account the needs of persons with reduced mobility, families and children.
Policies and governance
Sustainable transport policies have their greatest impact at the city level. Outside Western Europe, cities which have consistently included sustainability as a key consideration in transport and land use planning include Curitiba, Brazil; Bogota, Colombia; Portland, Oregon; and Vancouver, Canada. The state of Victoria, Australia passed legislation in 2010 – the Transport Integration Act – to compel its transport agencies to actively consider sustainability issues including climate change impacts in transport policy, planning and operations.
Many other cities throughout the world have recognised the need to link sustainability and transport policies, for example by joining Cities for Climate Protection.
Community and grassroots action
Sustainable transport is fundamentally a grassroots movement, albeit one which is now recognised as of citywide, national and international significance.
Whereas it started as a movement driven by environmental concerns, over these last years there has been increased emphasis on social equity and fairness issues, and in particular the need to ensure proper access and services for lower income groups and people with mobility limitations, including the fast-growing population of older citizens. Many of the people exposed to the most vehicle noise, pollution and safety risk have been those who do not own, or cannot drive cars, and those for whom the cost of car ownership causes a severe financial burden.
An organization called Greenxc started in 2011 created a national awareness campaign in the United States encouraging people to carpool by ride-sharing cross country stopping over at various destinations along the way and documenting their travel through video footage, posts and photography. Ride-sharing reduces individual's carbon footprint by allowing several people to use one car instead of everyone using individual cars.
Recent trends
Car travel increased steadily throughout the twentieth century, but trends since 2000 have been more complex. Oil price rises from 2003 have been linked to a decline in per capita fuel use for private vehicle travel in the USA, Britain and Australia. In 2008, global oil consumption fell by 0.8% overall, with significant declines in consumption in North America, Western Europe, and parts of Asia. Other factors affecting a decline in driving, at least in America, include the retirement of Baby Boomers who now drive less, preference for other travel modes (such as transit) by younger age cohorts, the Great Recession, and the rising use of technology (internet, mobile devices) which have made travel less necessary and possibly less attractive.
Greenwashing
The term green transport is often used as a greenwash marketing technique for products which are not proven to make a positive contribution to environmental sustainability. Such claims can be legally challenged. For instance Norway's consumer ombudsman has targeted automakers who claim that their cars are "green", "clean" or "environmentally friendly". Manufacturers risk fines if they fail to drop the words. The Australian Competition and Consumer Commission (ACCC) describes green claims on products as very vague, inviting consumers to give a wide range of meanings to the claim, which risks misleading them. In 2008 the ACCC forced a car retailer to stop its green marketing of Saab cars, which was found by the Australian Federal Court as misleading.
Source from Wikipedia
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