Prof Dr Martin Kesternich in an interview with Deutschlandfunk Kultur
Germany, known for its motorways without a general speed limit, has been discussing the introduction of speed limits for years. But what impact would such a measure actually have? How would different speed limits affect traffic dynamics, emissions and accidents?
Those in favour argue that speed limits could help to reduce accidents, noise and environmental pollution and improve road safety. However, there is still a lack of evidence-based arguments in many areas of the discussion that could objectify the debate.
In an interview with Deutschlandfunk Kultur,Martin Kesternich, Professor of Economics, in particular sustainability, at Paderborn University and spokesperson for the Paderborn Research Centre for Sustainable Economy (PARSEC), emphasised the importance of controlled intervention studies in the context of a real-world laboratory. Such studies are crucial in order to systematically determine the effects of a speed limit on various factors such as climate impact, pollutants, noise and road safety. A simple before-and-after comparison is generally not sufficient here and, in the worst case, could even lead to false conclusions. In a field experiment, on the other hand, randomly selected motorway sections would be given a speed limit over a longer period of time and compared with equally randomly selected control sections without a speed limit. "This would allow us to provide a serious answer as to how the introduction of a speed limit would affect the various target dimensions," explains Kesternich. What is missing so far is the political will for such a comprehensive study.
You can find the article on the topic "Speed limit - is there a research gap?" here.