In 2008, for the first time, over half the world’s population was living in towns or cities. By 2030, this will be five billion people.
In developing countries in Africa and Asia, the number of people living in cities grows by an average of five million new residents every month – more than the current population of Singapore.
The towns and cities growing fastest will need to provide food, water, shelter, energy, and security for their rising populations, and quickly, at their present rate of growth.
Cars running on petrol or diesel produce gases, including carbon dioxide, which are bad for the environment. As oil becomes more expensive, and as we use more of it, scientists are looking into alternative methods of transport.
Poor air quality as a result of exhaust fumes is worst in areas with high traffic congestion, in towns and cities where many people rely on cars. As more people move to towns and cities the number of cars on the road will rise, resulting in greater problems with traffic and pollution.
Many businesses and organisations are involved in schemes encouraging their workers to travel to work on foot, or by bicycle or bus, to cut down on car use and reduce pollution. Chemical scientists are also looking into designing electric cars, or trying to find different fuels that can be used to run cars more cleanly.
Green cars are also being looked into by the motorsport industry, which is not only trying to make cars go as fast as possible, but also more efficient and less polluting. One car manufacturer recently introduced a car that runs on bio-ethanol, has a top speed of over 200mph and goes from 0-60mph in 3.5 seconds.
Adjustments made by scientists and engineers, including increasing the size of the fuel tank and upgrading the fuelling system, have made bio-ethanol a race-winning reality, while reducing carbon dioxide emissions by up to 70%.