TRANSPORT

©1996 This is an original document writeen by ECO Centre staff.  You will find much more uptodate research and facts and figures elsewhere.

Roads, Cars, People and the Environment

Invented a little over a century ago, the car has come to be embraced to the extent where it is now an essential part of our lives. The car offers freedom and almost unlimited mobility; we can jump into its comfortable, upholstered, seats at any time - day or night - and be transported, over a sophisticated network of roads, to wherever we wish. We love our cars. They come with us on holiday, rush us to work, ferry the kids to school, carry our shopping. In return we lavish money on them, feed them on demand, wash them, keep them clean, make sure they are in good health. For many of us, life without the car would be hard to imagine. Life without a car can indeed be difficult. So absorbed has it become into our culture that we have come to rely on it. In the past, people used to live near to where they worked. Now they commute. Once, people walked to their local shops to buy fresh, local produce. Now they have a weekly trip in the car to the not so local out-of-town supermarket. Twenty years ago most seven to eight year old children walked to school. Now, they are driven; their parents justifiably concerned about their safety should they choose to brave the traffic. Not only is the car affecting the way we live our lives, it is also affecting our health. Not only is it affecting our health, but the health of our wildlife and countryside. Ultimately, it is also affecting the health of our planet and future generations. This fact sheet explores some of the effects of our love affair with the car and road transport and then goes on to look into the ways by which we can do our bit to minimise them.

Road traffic emissions

Emissions from the burning of petrol and diesel by road traffic are responsible for exacerbating climate change, acid rain and air pollution. The effects of road transport emissions are both global and local. Climate change, caused by the over production of 'greenhouse gases', offers a very real threat to the survival of our planet. Acid rain destroys our forests, lakes, and rivers, as well as the life to which they play host. Air pollution affects health directly, leading to respiratory problems such as asthma. Carbon dioxide (CO2) - Road traffic accounts for a fifth of the UK's annual CO2 production. CO2 is the principal greenhouse gas. Emissions can only be reduced by reducing the amount of fuel burnt: by (1) reducing the number of miles travelled, and (2) travelling in the most fuel efficient ways. Nitrogen oxides (NOx) - Half of all NOx emissions come from motor vehicles. NOx leads to smog formation, and, in the UK, is becoming the major contributor to acid rain. Another acid gas, sulphur dioxide (SO2), is also released by motor vehicles, albeit in lower quantities than from other sources. Carbon monoxide (CO) - Road vehicles produce 90% of the UK's CO emissions. When inhaled, CO has direct effects on health by reducing blood oxygen levels. Symptoms include fatigue, stress, headaches and respiratory problems. In the atmosphere, CO eventually becomes converted into CO2, and therefore also contributes, indirectly, to climate change. Hydrocarbons - Hydrocarbons are present in the vapours emitted by unburnt petrol whenever it is exposed to air: during 'fill-ups' at the garage, and from vehicle exhaust. They undergo photochemical reactions in the atmosphere to form hazardous compounds, many of which have serious implications for human health. Benzene, for instance, is a known carcinogen. Lead - Fortunately, the use of lead as an additive in petrol is now being gradually phased out. In the body, lead is an accumulative poison, shown to hinder mental functioning. Children are particularly affected. Particulates - Particulate matter (smoke) is the most conspicuous of the emissions - it can be seen! Diesel-powered vehicles are the biggest offenders and road transport as a whole is the major source of smoke in the UK. Some components of particulate matter may be carcinogenic. Catalytic converters can help to reduce many of these emissions. However, some important points should be borne in mind: (1) they only work when the engine is warm and are therefore largely ineffective for short journeys; (2) they can only be fitted to petrol-engined vehicles; (3) they are easily damaged, e.g. through the use of leaded petrol; (4) they do not reduce CO2 emissions. Electric cars are often cited as 'the way forward' on the basis that they appear not to produce emissions. In the US, such cars are known as 'ZEVs' (zero-emission vehicles). However, this can be misleading. Electric cars require as much, if not more, energy to run than conventional cars. This energy comes in the form of electricity, generated, more often than not, from fossil fuels or nuclear power, and carrying similar pollution implications to the energy provided by conventional motors. The difference with ZEVs is that the pollution is not emitted locally, hence, in already polluted, urban environments, the use of such vehicles may be of some benefit.

Social effects of road transport

Society is increasingly building itself around the motor car, and, as this happens, people are becoming increasingly isolated from one another. Communities are beginning to fall apart. The large, anonymous leisure and shopping facilities cropping up on the outskirts of towns and cities are leading to a decline in the use of local shops and services. Long-distance commuting is leading to rural areas becoming occupied by people with neither the time nor the inclination to invest in their local community. All the while, inner city areas become ever less populated and, as a consequence, ever less habitable places to be. The very nature of driving - sitting in a 'safe', enclosed space, separated from the outside world - is cutting us off from society at large and the natural world around us. The invention that can provide us with almost the ultimate in mobility, is, in fact depriving us of accessibility. The more mobility we have, the more mobility we seem to need in order to gain access to our needs. For society as a whole, car-use becomes like an insidious habit or addiction; the number of miles we need to travel goes on increasing. Those who lack the mobility - those without a car - become deprived of access to their needs and, increasingly, marginalised.

Health effects of road transport

Road transport kills over 3500 people each year, and maims and injures many more. Imagine the outrage if rail, air, or bus transport claimed so many lives. Aside from 'accidents' there are health effects linked to vehicle pollution, such as asthma, which kills 2000 people a year in the UK (note - recent studies have shown that people sitting in cars actually tend to absorb higher levels of vehicle-borne pollutants than other road users such as cyclists and pedestrians). On top of all this there are the incalculable negative health effects of the stress and inactivity resulting from the hours people spend behind the wheel each week.

Road building, wildlife and the countryside

The building of new roads is burying more and more of our countryside in tarmac and aggregate. The general disturbance that this causes includes the loss of open spaces, the alteration of water tables, and an increased threat of pollution run-off to surrounding areas. On top of this, countryside is destroyed many miles away, in areas such as the Peak District and the Mendip Hills, as they are quarried to provide the minerals required to make the road

New road building at Twyford Down

An often overlooked aspect of road transport is its detrimental effect on wildlife. The annual slaughter is extensive: 47,000 badgers a year - a fifth of the adult population; 5,000 barn owls - enough to seriously reduce populations in many areas; and around one in three amphibians each spring, as they attempt to migrate to their breeding areas. As traffic volumes increase, especially in rural areas, species such as these may become at risk of extinction. The problem of death on the roads is compounded by the destruction wrought on wildlife habitats arising from new road building. Recent developments, such as the Newbury Bypass, have been driven straight through Sites of Special Scientific Interest (SSSI's) - an area designated as a SSSI is supposed to afford the highest category of protection to the important variety of wildlife it shelters.

Car use and energy consumption

The car uses a particularly large amount of energy to transport people over a given distance, when compared with alternative modes of transport. The main reason for this is that the number of occupants in the car tends to be low - often just the driver. The table shows the differences in energy use per passenger mile for the different modes of transport; average occupancy rates have been assumed. From the table it can be seen that cycling is by far the most energy-efficient mode of transport, followed by walking, then buses and trains. Car use is the least efficient; however, by increasing the number of people in the car and by limiting its use to the open road, its efficiency may be greatly improved.

Energy consumption of different modes of transport. (Source: Transport 2000)

Minimising the damage

As can be seen, the effects of road transport on the way we live and our environment are multifarious. Minimising these effects will require input from government:

• diverting funding from road building to public transport
• traffic calming residential areas to make the streets safer to walk on and providing facilities to encourage more cycling
• preventing the further development of car oriented out-of-town shopping and leisure facilities

Such policy measures could help to smooth the way for a less car dependent society. In the meantime there are measures that we can take to ensure the most responsible and least environmentally damaging use of the car.

Make the most out of each journey

The best way to minimise the detrimental effect of the car is to leave it at home:

• for short journeys, walk or cycle. At most this will take a few minutes longer, in many cases you will save time. Whichever is the case the environment and your health will benefit - it has been estimated that a 10% increase in the number of people cycling would lead to a 4% decrease in the incidence of heart disease, saving the NHS £200 million a year.
• try to make use of public transport for regular journeys such as getting to work. Our deregulated public transport system can only exist if sufficient people use it; the more it is used the better the services will become.

Obviously it is not always practical to leave the car at home:

• for each car journey that is made, try to make the most of it, i.e. fit as many errands into the one journey as possible, for instance by combining a shopping trip with a visit to friends, cinema, etc.
• give other people lifts - better to fill one car with four people than to have four cars, each carrying just one.
• always use 'park-and-ride' facilities where they exist.

Improve your fuel economy

By ensuring that, for a given mileage, as little as possible fuel is used, it is possible to ensure that the impact of motoring, especially on the global environment, is minimised. Petrol and diesel contain carbon, this carbon is released into the atmosphere as CO2, the principal greenhouse gas, when the fuels are burnt. If the fuel must be burnt then it should be burnt as efficiently as possible, thereby minimising CO2 emissions. This may be achieved by:

1. maximising the efficiency of your driving
2. maximising the efficiency of your car.

Maximise the efficiency of your driving

The way you drive your car is the single most important factor in determining fuel economy. A car driven smoothly will use around 30% less fuel than a car driven erratically. Avoiding harsh acceleration, sudden braking and excessive speed, selecting the correct gear, and driving with anticipation, is not only safer but can also save a fortune in fuel bills. Speed - most cars are designed to operate at their maximum efficiency when driven at a constant speed of between 35 and 60mph, in top gear. With an average car, driving at a constant speed of 75mph will use around a quarter more fuel than driving at a constant 56mph. In stop-start urban driving conditions, the car will use around 60% more fuel - driving in congested areas or at busy times of day should be avoided wherever possible.

Don't drive like a maniac Use of gears - where it is safe and appropriate to do so, the use of a higher gear can effect significant reductions in fuel consumption. However, care should be taken not to labour the engine. Use of electrical equipment - electricity in the car is not free; it is generated by diverting some of the power of the engine to charging the battery. This uses fuel, fuel that will be wasted if electrical equipment is being used ineffectively, e.g. by forgetting to switch off the rear window de-mister when it is not required. Features such as air-conditioning, largely superfluous in the UK, tend to use particularly large amounts of power, a typical unit increases fuel consumption by around 8%. Opened windows - driving at speed with the windows wide open increases fuel consumption by reducing the aerodynamic efficiency of the car. At 60mph, with all the windows open, the typical car uses 2% more fuel. Loading - each percentage point by which the weight of a typical car is increased results in a corresponding 1% rise in fuel consumption. Hence, leaving 40kg of tools in the boot of an 1000kg car will increase its consumption by 4%. If the weight is carried on the roof the problem is compounded by a reduction in aerodynamic efficiency. At a constant speed of 70mph, a loaded roof rack can increase fuel consumption by a staggering 27%. Where possible, roof racks should be avoided - if the car is full, consider transporting the extra load in a low trailer. Caravans - when towing a caravan or high trailer, fuel consumption increases. Part of the increase is due to the decrease in aerodynamic efficiency. This problem can be minimised by fitting an airfoil to the roof of the car; if properly fitted, this could make a difference in fuel consumption of up to 25%.

Maximise the efficiency of your car

A well-maintained car will consume less fuel than a badly maintained car. It will also be less likely to break-down. The costs of adequately servicing your car should soon be paid back in reduced expenditure on both fuel and wear and tear.

Keep your car well maintained

Spark plugs and tuning - spark plugs should be changed at intervals of no more than 10,000 miles; one faulty plug can increase fuel consumption by 5%. Correct tuning - checking and adjusting the carburettor, ignition, valve clearance and air filter - can improve petrol consumption by a further 5%. Finally, savings can be made by ensuring that the engine idles at the correct speed, particularly if the car is mainly driven in urban areas.
Wheel alignment - misalignment of the front wheels of your car causes accelerated tyre wear and can significantly increase fuel consumption. One degree of misalignment in both front wheels will increase fuel consumption by around 3%; two degrees increases this to 10%. Wheels should also be properly balanced, and the brakes should be checked to ensure there is no binding.
Tyres - always ensure that your tyres are correctly inflated. Under inflated tyres increase rolling resistance and therefore fuel consumption: tyres that are 20% under-inflated increase fuel consumption by around 5%, as well as suffering increased wear.

Buy the least environmentally damaging car

When choosing a new car, put fuel efficiency at the top of your agenda. Many of today's car advertisers promote the sheer power, style and romance of driving a sleek machine through unspoilt traffic-free countryside in exotic locations. Try to be realistic: most of your driving will not be in such situations. Instead, the car is likely to be used for more mundane things such as getting the shopping - negotiating traffic jams as opposed to sweeping hairpins on idyllic mountain tracks. In such circumstances, power and style become very much secondary to efficiency, economy, and practicality. The car is simply a tool that gets you from A to B - let your local dealer know that you are not prepared to be drawn into marketing ploys that attempt to promote it as anything else. This way you can save money, reduce your impact on the environment, and hopefully, eventually, persuade manufacturers to start producing more appropriate vehicles. The recent fad for big four-wheel drive, 'jeep' type vehicles is of perhaps the most concern. Traditionally used by farmers for off-road use, these machines have now become de rigeur for many town and city dwellers. While these vehicles may impart a sense of security in their owners, this tends, unfortunately, to be at the cost of other road users. Their 'bull-bars' have been shown to cause irreparable damage to the bones of any unfortunate pedestrians who step into their path. Their grossly oversized and inefficient engines chug away to provide as little as 15 miles to the gallon, spewing out excessive levels of pollution as they go.

Summary

This fact sheet has explored some of the more negative social and environmental aspects of road transport. It has not been intended to convey too pessimistic an impression, rather to point out some of the often overlooked effects of our motoring and how, at least to some extent, these may be mitigated. While the practicality and value of the car is recognised, so too is the need to apply a sense of proportion in its use. It is the inappropriate use of the car that is the problem, not so much car ownership. Cars do have a place in modern society; by taking steps to utilise our cars in the most efficient and effective ways we can ensure that they retain their place without impinging excessively on the rest of society. Think before you drive!