Traffic is one of the main causes of the most serious environmental problems worldwide. Accidents, photochemical air pollution, climate change, air quality and noise levels are some of these factors. The challenge of today is how to reduce these negatives effects in the coming years. As “sustainable development” and “sustainable consumption” are getting more important or even becoming preconditions for a better environment, the tendencies within road traffic can be labeled as “unsustainable,” i.e. the number of vehicles is still rising and consumption of oil and contribution to CO2 emissions remain high. Kroon (1998) suggests that only a forced decline in the average fuel consumption per km of at least 50% between 1998 and 2010 will have an effect on reducing CO2 and other emissions. In the opinion of Kroon (1998) this was denoted as a feasible target if technical vehicle improvements were geared more towards fuel efficiency instead of upgrading power, performance and weight and if, at the same time, driver behavior could be guided towards fuel efficiency and away from speeding and strong acceleration. Within the last decade, it is still noted that the trend for more powerful engines and higher performance still exists and that the policy of car manufactures to counter the problem is scantily made. These powerful vehicles will also influence road safety and feelings of security and safety of other road users. Accidents and fatalities will increase when speed levels increase, but also the weight and size of vehicles can effect the security of drivers and other road users.
For several years, the Institute of Sustainable Mobility conducts studies on the evolution of weight, engine power and speeds of the sold vehicles in Belgium. The first results of 2007 indicate that there is still an increase in power, weight and speed. In this paper the results and the problem of bigger cars will be described on different level
