In this paper we investigate first both the effects (and social costs and benefits) of reducing speeds as well as the acceptance of speed policies. The reductions found are considerably and may in a rather extreme case for example result in reductions of C02 by 20 per cent, NOx by 40 per cent and reductions in fatal accidents by 30 per cent. On the other hand, however, travelling time increase, hence resulting in 'costs' of reducing average speeds. The societal cost-benefit analysis shows that reducing and enforcing speed limits will lead to significant savings for society, varying from DFL 0.5 bln to DFL 3.2 bln depending on the assumptions made. However, the acceptance of speed policies is more problematic. This holds especially for certain groups such as younger people, men and people with high incomes. Current speed limits are transgressed frequently. The association with psychological factors (personal freedom, makes car driving nicer etc) is in particular important. This holds in particular on highways where according to our calculations the highest benefits can be achieved. Also electronic speed limiters are hardly accepted. In conclusion, if governments desire to change speed policies, especially the impacts on road safety should be stressed and policies may in the beginning focus on roads in built up areas. Particular attention should be given to the psychological factors of speed. It will be hard to get such a policy accepted. If government succeeds, however, the benefits for society will be substantial. (Author/publisher)
Abstract