Mobility Policy

    Why there are better solutions than a rigid speed limit

    In Germany, there are repeated discussions about introducing a general speed limit. Yet this would not be the answer to the problems it aims to solve.

    In Germany, there are repeated discussions about introducing a general speed limit. Yet this would not be the answer to the problems it aims to solve.

    A rigid speed limit is not the answer to the problems it aims to solve

    In the political debate, there are repeated calls for a general speed limit in Germany – i.e., also on highways (autobahn).

    From the automotive industry's point of view, however, the approach of a recommended speed of 130 km/h on the autobahn has proven its worth. Instead of blanket limits, precise speed limits should be applied only where it makes sense, e.g., on highway sections with an increased risk of accidents or due to the structural situation (e.g., curved or downhill sections). In addition, flexible speed limits can be displayed by traffic control systems depending on the current weather or traffic conditions, and these dynamic limits are more widely accepted among motorists. By contrast, rigid speed limits – as indicated by metal signs – which always display one and the same maximum speed for all traffic and weather conditions are contrary to a modern traffic system of the 21st century. Moreover, increased digitization of vehicles and infrastructure will further improve the conditions for situation- and route-dependent regulations.

    The autobahn is the safest road

    Highways are our safest roads. The risk of being killed on a rural road, for example, is about 3.5 times higher. Road safety policy should instead focus on rural roads. Moreover, the autobahn is getting safer still: Between 2000 and 2020 alone, the number of fatalities on German highways fell by around two-thirds. Much of this is due to equipping vehicles with the latest driver assistance systems. Even in an international comparison, there is no discernible correlation between a blanket speed limit and the level of safety on highways. Countries with general speed limits on highways, such as Belgium, France, Italy, or Austria, do not perform better than Germany statistically. In addition, there is no evidence of more accidents in Germany on stretches of autobahn without a speed limit than on those with one.

    Fig.: Comparison of non-urban roads – Deaths per billion kilometers driven (2020)

    Source: BASt

    A speed limit would have little CO2 effect

    A general speed limit in Germany would also only have a tiny effect on climate protection. For example, a speed limit of 120 km/h would reduce German greenhouse gas emissions by hardly more than 0.2%. In addition, it would be a very expensive measure toward climate protection: The Kiel Institute for the World Economy has calculated that – if the time lost associated with speed limits is taken into account – the cost per ton of CO₂ saved is between €716 (for a 130 km/h speed limit) and €1,382 (for a 100 km/h speed limit). Leading the Institute to conclude that a general speed limit should be rejected for economic reasons.

    General speed limit on highways ineffective noise abatement

    A general speed limit on the German autobahn cannot contribute to noise abatement, either. When the amount of heavy goods traffic exceeds 10% – which is the case on more than 95% of the highways – the noise from cars no longer plays a role. This was also demonstrated by a large-scale test on the A 45.

    Dr. Michael Niedenthal
    Contact person

    Dr. Michael Niedenthal

    Head of Transport Policy Department

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