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High-volume Semi-trailers

Volume 533: debated on Tuesday 11 October 2011

Further to my statement of 30 March 2011, Official Report, column 23WS, the Department for Transport has today published its response to the consultation on a proposal to allow a 2.05 metre increase in the length of semi-trailers and a maximum overall length for articulated heavy goods vehicles of 18.75 metres.

The research underlying the consultation proposal suggests that high volume semi-trailers have potential environmental, safety and congestion benefits: they would allow up to 13% more loading space than current articulated lorries, resulting in fewer journeys needed to transport the same volume of goods. The research predicts that by 2015 this would reduce lorry miles in the UK by 100 to 180 million a year, meaning reduced congestion, reduced air pollution and reduced carbon emissions (by around 100,000 tonnes a year reduction). The research also found that there would be a net decrease in casualties of around 1.6% from the reduction in lorry miles.

However, the evidence provided during the consultation exercise has identified a number of areas which merit additional investigation. These include possible effects if the number of longer semi-trailers introduced is significantly higher than that predicted by the research and the impact assessment attached to the consultation document; the impacts of longer semi-trailers on road infrastructure and design and on depot and distribution centre infrastructure and design; the impacts on SMEs of allowing longer semi-trailers; and the effectiveness of additional vision/sensor/safety systems fitted to improve detection of vulnerable road users.

The research underlying the consultation proposals was comprehensive. To gather further evidence on such impacts will therefore require a trial of longer semi-trailers in operation. The Department therefore intends to proceed with an operational trial of longer semi-trailers in order to gather practical evidence. Trailers taking part in the trial will operate under Vehicle Special Orders issued under section 44 of the Road Traffic Act 1988.

The Department considers that the number of vehicles permitted in the trial will need to be limited, but that the number permitted should still allow meaningful evidence to be gathered on the likely take-up of longer semi-trailers across the vehicle fleet as well as their impact on infrastructure. This would require a trial of vehicle numbers that allows operators to swap a sufficient percentage of their fleet over to the longer semi-trailer to enable them to remove standard trailers from their fleet and make an effective comparison of performance.

The responses to the consultation also indicate that different businesses would wish to choose between additional trailer lengths of up to 1 metre and up to 2.05 metres, depending on the nature of their business. The trial provides an opportunity to validate the impacts of each length. The current trailer parc for articulated vehicle above 40 tonnes in the UK is estimated at around 100,000 trailers. The Department intends to proceed with a trial of up to 900 trailers of an increased length of up to 2.05 metres; and 900 trailers of an increased length of up to 1 metre, 1,800 trailers forming just under 2% of trailers on British roads.

Our baseline research shows that the ability to operate longer semi-trailers would provide clear benefits to business and a spur to efficiency and growth. We expect the trial itself to offer a net present value of £33 million, largely due to the financial benefits operators should see over the 10-year length of the trial (around £1,800 per vehicle per year). We would expect many of these benefits to flow through to the consumer.

Participation in the trial will be on a voluntary basis and at the participants’ own risk; there is no guarantee that the use of the longer semi-trailers will continue to be permitted beyond the end of the trial period. The trial will run for 10 years, to allow those businesses wishing to participate the opportunity to cover the costs of investment in the longer semi-trailers. Expressions of interest are invited from today, with the trial starting in January 2012. Information on how to apply can be found on the DfT website.

However, the Department wishes the trial to be closely monitored, to ensure that any significant issues, particularly on safety, that arise are addressed quickly and to ensure that the trial is meeting the Department’s objectives. The Department will therefore appoint an independent contractor to monitor and review trial progress. The contractor will report to the Department on a four-monthly basis; at the end of each trial year the Department will review progress towards objectives, including considering any changes to the length of the trial and the numbers of trailers involved in the trial.

Although many of the responses from vehicle operators supported the development of tractor units with a safer more aerodynamic frontal design, it was evident from the majority of responses received from vehicle manufacturers that they are unlikely to progress with the development of improved frontal designs at this time. Therefore, the Department has decided not to include tractor units with an extension of up to 0.4 metres for improved frontal designs in the trial. However, we are keeping the situation under review.