The installation of speed limiters and Intelligent Speed Adaption Systems (ISA) is believed to be an effective way to improve road safety and to reduce emissions and traffic noise. It addresses specifically unadapted driving speed, which is one of the main causes of traffic accidents, particularly on motorways. Speed policies can be regarded as being complementary to other policies that affect other causes of accidents or emissions, such as vehicle and energy technology, alcohol use or unsafe infrastructure. Directive 92/6/EEC required speed limitation devices to be installed on large Heavy Goods Vehicles HGVs and buses (N3 and M3 vehicles). In 2002, this "Speed Limitation Directive" was amended by Directive 2002/85/EC, which obliged all Heavy Commercial Vehicles (HCVs), so also N2 and M2 vehicles, to be equipped with speed limiters. Directive 2002/85/EC requires the Commission to evaluate its road safety and traffic impacts. In this context, the European Commission commissioned Transport and Mobility Leuven, CE Delft, TRT and TNO to carry out this evaluation study. Speed limiters and ISA can contribute to key policy objectives of the 2011 White Paper on Transport, in particular moving closer to zero fatalities in road transport in 2050 and reducing GHG emissions in 2050 by 60% compared to 1990 level. Speed policy can be regarded as necessary, but on its own not sufficient for meeting these targets. The main argument for the EU to keep playing a role in speed policy appears to be to ensure a level playing field for all commercially used vehicles across Member States. The overall objective of this study is to assist the European Commission with the ex-post evaluation of the "Speed Limitation Directive" and to explore and assess options for revising the Directive (ex-ante evaluation). These options include changing the maximum speed applied for HCVs, extending the scope of the Directive to Light Commercial Vehicles (LCVs, including Light Goods Vehicles and small buses, respectively N1 and M1 vehicles) and/or introducing requirements for the installation of various types of ISA. The analysis builds on a literature review, a survey among stakeholders and Member States, interviews, a stakeholder workshop and extensive data analysis and modelling. According to the survey carried out in this project, no particular problems have been encountered in the implementation of the Speed Limitation Directive with few exceptions related to administrative and technical costs. All Member States that replied to the questionnaire (63% of all EU Member States) applied the maximum speeds set out in the Directive and regularly check the vehicles' compliance. In most cases this is done during roadside inspections and/or during yearly roadworthiness tests. The impacts of the Directive on actual vehicle speeds are hard to estimate due to data limitations. When comparing the scarcely available historical data on traffic speeds, no clear effect of the Directive on the speed distribution could be found. The statistical analysis of the evolution of the accident risk of HCVs gave no clear evidence of the impact of the Directive on traffic safety mainly due to data limitations. However, the speed distribution without speed limiters of 10 years ago might not be representative for a situation today without speed limiters. Therefore a second approach was applied, based on relationships between the speed distributions and accident rates and the impact of speed limiters on the speed distributions. Hence, based on real data, more theoretical speed distributions were assumed as well as the effect of speed limiters on these distributions. Using these speed distributions with and without speed limiters, the impacts on safety and emissions were calculated. This analysis showed that the Directive had a positive impact on traffic safety. Overall the impacts are estimated to be a reduction of 9% of fatal accidents on motorways with HCVs involved, 4% of serious injuries and 3% of injury accidents. The total reduction in the number of annual fatalities due to the Speed Limitation Directive is estimated at about 50 a year. These results should be regarded as indicative. Unfortunately, data is lacking to distinguish the road safety impacts of introducing speed limitation devices specifically in vehicle categories N2 and M2. The effects on emissions were estimated by comparing speed profiles. This analysis showed that for the EU as a whole the introduction of speed limiters resulted in a reduction of the total CO2, NOx and PM emissions of HCVs of about 1%. The evaluation of the market impacts focused on the possible impacts on a shift between HCVs and LCVs, the transportation costs, vehicle design and enforcement and fraud. For none of these impacts clear evidence of problems were found. With respect to shifts towards LCVs, some countries did see this shift, but this could also be caused by other regulations and other influences. Fraud was not seen as a problem by the interviewees, but did come up as a problem in the literature from outside the EU. Four scenarios for HCVs were evaluated and four for LCVs. Unfortunately, data is lacking to evaluate the impacts of extending the scope of the Directive to commercially used M1-vehicles. Therefore, the LCV scenarios were limited to LGVs (N1 vehicles). The results for N1 vehicles can however be expected to be representative for commercially used M1 vehicles, given that the parameters determining the safety and emission impacts are largely the same. The analysis shows that overall the ISA scenarios have the highest reductions on road safety for both HCVs and LCVs, in particular when the system is not just informative but also gives active feedback (Voluntary ISA). For both HCVs and LCVs the scenario with such an ISA system shows a reduction in the number of accidents in the EU with HCVs/LGVs involved of about 25% for fatal accidents, 18-19% for seriously injury accidents and 11% for all injury accidents. This corresponds to a reduction in the number of fatalities per year of about respectively 150 (ISA for HCVs) and 600 (ISA for LCVs). Decreasing the speed limits to 80 and 90 km/h for HGVs and buses, respectively, leads to a decrease in fatal accidents with HCVs involved of about 5%. A similar reduction percentage was found for the scenario with speed limiters for LGVs set at 100 km/h. These rates are lower than for the ISA scenarios because speed limiters do only affect motorway traffic and rural roads with relatively high posted speed limits; ISA systems have an impact on safety on all roads. Because the absolute number of accidents is larger for these road types, ISA systems have a larger overall effect on road safety. It should be noticed, however, that speed limiters are an effective way to improve traffic safety on motorways: it allows for 16% to 28% reduction of fatal accidents with LGVs involved (corresponding to 40 to 70 fatal accidents a year) The emission impacts are rather different from the safety impacts: the speed limiters can have a high impact on emissions, especially on motorways, while the effect of ISA is in most cases close to zero. The highest emission reductions for the HCVs are found when the speed set with the speed limiters is lowered to 80 and 90 km/h for HGVs and buses, respectively. In that case both pollutant and CO2 emissions decrease with approximately 4% to 6% of the emissions by HCVs on nonurban roads in the EU27 (corresponding to a reduction of about 9 Mt of CO2). For LCVs, the highest emission reductions are found for the scenario with a speed limit set at 100 km/h with emission reductions on all non-urban roads of about 4-5% for CO2 (about 2 Mt of CO2) and PM emissions and even 14% for NOx. With a speed limiter set at 110 km/h, emissions reductions are less than half as high. The extension of speed limiters to LGVs is generally seen as a way to reduce vehicle operating and maintenance costs. In combination with the CO2 emission limits for LCVs it could also lead to engine power downsizing resulting in additional CO2 reduction. Concerning compliance costs, the Directive extension would imply measures for the retrofitting of the existing fleet and ad-hoc enforcement policies will have to be applied in order to avoid frauds and illegal behaviours. Further decreasing the speed for HCVs can be expected to result into a shift towards the less restricted LCVs and possibly lead to a positive effect with respect to the operating costs. The LCV scenarios with speed limiters are considered by some stakeholders and operators as a step towards a more levelled playing field in road transport. However, speed is not the only factor influencing the choice of the commercial vehicle size. When just N1-vehciles would be included, there might be a shift from LGVs to M1 vehicles, which is an argument to include commercially used M1 vehicles also to some extent. No major market impacts are considered for the ISA scenarios, both for HCVs and LCVs. The results of the ex-ante evaluations suggest that there is no need to change the speed set with the speed limiters for HCVs. There is also not much support among stakeholders and Member States for doing so. On the other hand, based on the ex-ante evaluations, there are several options for improving the effectiveness of the Speed Limitation Directive, in particular: To improve traffic safety, requiring all commercial vehicles to be equipped with an ISA system that provides tactile feedback to the driver (for HCVs combined with the existing speed limiter). For reducing emission, introducing speed limiters for LCVs is an effective measure. In the evaluation carried out in this study it was not feasible to simulate scenarios with subsets of N1 or M1 vehicles covered by the Directive. However, to ensure a level playing field and to avoid unintended shifts, e.g. between N1 and M1 vehicles, policy options for including certain types of M1 vehicles could be considered. This topic is recommended as subject for further study. (Author/publisher)
Abstract