Project: Longer and/or longer and heavier goods vehicles a study of the effects if they were to be permitted in the UK

Reference: S0516/V7

Last update: 11/12/2008 11:47:27


The objective of the study was to assess what the effects might be if different types of longer and/or longer and heavier goods vehicles (LHVs) were to be permitted in the UK. The purpose was not to advise on whether to allow trials, but to better inform any future decisions on LHVs in light of the Better Regulation initiative, the Eddington and Stern reports, and proposals from the European Commission planned for summer 2008 to amend the rules on goods vehicle weights and dimensions.


This study assesses what the likely combined effects on road safety, the atmospheric and built environment, and the efficiency of freight transport, including the effects on modes other than road transport, might be if different types of LHV in excess of the current weights and/or dimensions limits were to be permitted in the UK.

This involved reviewing the scientific literature, analysing freight data, gathering information from stakeholders, modelling existing road freight flows and undertaking computer simulations of vehicle performance. A wide variety of factors were assessed, including but not limited to:

- potential demand for LHV operations
- economic efficiency of such operations
- effect on other freight modes and the potential impact of freight traffic generation
- effect on the frequency and distance of vehicle movements
- effect on safety and accidents
- changes to vehicle emissions and the environment
- effects on infrastructure
- effects on drivers


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Contract details

Cost to the Department: £210,521.66

Actual start date: 03 November 2006

Actual completion date: 03 June 2008


Longer and/or Longer and Heavier Goods Vehicles (LHVs) a study of the likely effects if permitted in the UK
Author: I Knight, W Newton, Prof A McKinnon et al
Publication date: 03/06/2008
ISBN: 9781846087196
Source: TRL Online Store
More information:

Summary of results

  1. The results show that the larger types of LHV could not be operated in the UK without:

    - finding a mechanism to secure significant investment in improved parking facilities that drivers of large LHVs could use for statutory rest periods (rough estimates suggest that this could be in the low £billions if a new nationwide network of dedicated facilities proved necessary);
    - developing dedicated routes and the operational procedures to handle diversions and to enforce restrictions for some of the large LHV types and/or successfully negotiating tougher manoeuvrability standards in Europe; and
    - amending primary legislation (by way of regulations using the affirmative resolution procedure) to increase speed limits (currently set at 40mph on motorways and 20mph on other roads) so as to avoid the safety risks arising from vehicles travelling at significantly different speeds.

    The study also found, depending on take-up by the road transport industry and the level of mode shift from rail to road, particularly in the transport of shipping containers, that 60 tonne "super-lorries" could increase CO2 emissions by between 62,000 and 161,000 tonnes per year. If these larger LHVs were restricted to 50 or 44 tonnes, the impact on CO2 was seen to range from an annual saving of 122,000 or 247,000 tonnes respectively to an increase of 72,000 or 24,000 tonnes respectively. Given the uncertainty over the outcome, the report recommends additional work to validate the predictions if further consideration were to be given to large LHVs.

    As for safety risks, in the case of large LHVs, these would likely increase per vehicle km, but decrease per unit of goods moved, resulting in a small net reduction in fatalities. Tougher safety standards could be set to reduce the per vehicle km risk, increase the net reduction in fatalities, and stimulate wider use of new technologies in the goods vehicle fleet, but European law would not currently allow us to mandate such standards nationally.

    The analysis of internal and external costs suggests that the large LHVs could offer substantial savings in freight transport costs. However, the potentially significant capital investment costs (e.g. improved parking facilities) are such that it has not been possible to determine whether the benefit cost ratio would be positive or negative.

    However, the situation for articulated vehicles with longer trailers is different. These vehicles would not be restricted to lower speeds, nor require dedicated infrastructure, or necessarily require tougher safety standards - although there remains a low risk of challenge from the Commission or other Member States on the basis of European harmonisation rules. They would, however, represent a risk to a small mode shift overall from road to rail if the domestic intermodal market were to grow as expected. Taking this into account, as far as the available information - which is limited in relation to impacts on rail freight - allows, the researchers predict that these vehicles could deliver annual UK savings of around:

    - 45 to 66 thousand tonnes of CO2,
    - 57 to 85 million vehicle kms,
    - 276 to 682 thousand goods vehicle movements,
    - one or two road fatalities, and
    - £23 to £37 million in net freight transport costs.

Departmental Assessment Status: The project was extended beyond the original contract. The result highlighted a number of issues that allowed the Secretary of State to make a decision on whether to allow these vehicles on UK roads.