Select Committee on Environmental Audit Written Evidence

Memorandum submitted Greenspeed


  1.01  Greenspeed has been campaigning for over 10 years for regime change in the national speed limits from 70/30mph to 55/20mph. During that time traffic speed has been the subject of a number of reviews but these have not covered the full impact that our current speed limits on the economy, society and the environment. Despite the preoccupation on road "safety", the current speed regime continues to cause a level of loss to life and limb that imposes serious costs on the economy, the health services, emergency services, families and communities.

  1.02  On the recent/current DfT/Defra/DTI consultation on climate change, the section on transport from the Transport Secretary amounts to little more than an apology for the failure of transport policy to deliver on reductions of GHGs and assumes that the carbon burden will continue to increase despite some technological innovation and fiscal measures making marginal differences. This is presumably the basis of the concern of the Environmental Audit Committee.

  1.03  The problem for the transport sector is illustrated by the reference to the DfT review in July 2004 that the objective is to achieve "better access and greater mobility". The DfT is oblivious to the conflict between the worthy objective of increasing "access" and damage caused by increasing "mobility".

  1.04  Greenspeed is not only familiar with the reviews that have been carried out into speed, but has also carried out extensive correspondence with the DfT (and The Commission for Integrated Transport, IPPR, TRL, T2000 and others). Despite not having spent any of its £40 million research budget on the consequences of reducing the national speed limits, the DfT continue to believe that 70/30 represents the "best balance".

  1.05  A Division of the DfT is dedicated to looking at the feasibility of road pricing to deal with congestion, and believe that this could incidentally reduce GHGs. There is no division in the DfT tasked with looking at the effects of lower speed limits and the effect on GHGs. In fact the Secretary of State for Transport effectively ruled out road pricing by giving evidence to the Transport Select Committee in 2005 that it would be unwise to rely on large computer systems, just the type of system that would be required to monitor the movements of all 24-30 million cars wherever they happen to be on the road network. However, since that evidence the Transport Secretary has made a number of public statements suggesting that road pricing is the answer to congestion, apparently oblivious to the research carried out by Imperial College for the Energy Savings Trust that this could have the effect of increasing GHG emissions.

  1.06  Speed is not mentioned in the climate change consultation paper as either a cause of GHGs and a potential for GHG saving. Given the already well known advantages of lower speeds in terms of both congestion and GHGs, the question must be asked of Government (and the DfT) why this is not in the consultation together with indications of the potential of speed reductions. A Government cannot be taken seriously on climate change when it ignores the measure with perhaps the greatest potential for reducing GHGs, in the shortest timescale and at the least cost (not to mention wide-ranging and cumulative benefits). This omission means that Government will not benefit from comments on speed management from those involved in the climate change consultation.

  1.07  The most important research carried out in 2005 and published in 19 January 2006 is the VIBAT study by Bartlett and Halcrow. This shows that behavioural change (including a 50 mph speed limit) is the key if the transport sector is to contribute to the to the 60% reduction to GHGs that the Government require. The point is also made that savings made now reduce the severity of the changes that would be required later.

  1.08  This evidence concentrates on two of the issues raised by the EAC:

    —    the targets for CO2 reduction from the transport sector for 2010 and 2020 and,

    —    the specific steps that can be taken over the next decade, with reference to low carbon vehicles and demand management.

  1.09  When looking at the transport sector the Committee should have in mind that all impacts are a function of volume, mix and speed. In order to effect any significant changes, one of these fundamental elements must be targeted and there will be knock-on effects on the remaining two. It is not hard to see that speed is a factor that is already subject to regulation and stands out from "volume" and "mix" as being open to further modification.


  2.01  The transport system is very complex and without extremely sophisticated modelling it would not be sensible to attempt to quantify the level of the GHG reduction that would result from a national regime change from 70/30 mph to 55/20 mph. However, by their nature, systems contain and have the potential for virtuous circles or vicious cycles. This means that, if changes are introduced that "go with the grain", they create synergetic (see ODPM paper on EU Directive on Strategic Environmental Assessment and evidence of Chief Scientist to the DfT to the Select Committee on road pricing) and cumulative effects. If lower speeds can be shown to be part of, or even a trigger for virtuous circles that include GHG reduction, then further reductions can be achieved without further intervention. Measures taken to trigger virtuous circles can be very cost effective indeed. Those taken running against the grain will be wasteful of both money and time.

  2.02  In fact, it is well known that lower speeds do save GHGs. Because air resistance increases by the square of the speed, higher speeds can only be maintained with high levels of both fuel consumption and emissions. (recent research that shows that the most modern cars may not be significantly less efficient at higher speeds would only be relevant if there were no other substantial reasons to lower maximum speeds). It is also well known that lower speeds reduce congestion and that free-flow at moderate speeds reduces fuel consumption. Lower speeds also increase the capacity of both roads and junctions. None of the existing knowledge about slower speeds is rocket science and yet, due to the omission from the climate change consultation paper, Greenspeed may be alone in making the climate change case for reducing the national speed limits. Similarly, there were very few references to the role of speed management as an alternative to road pricing in the 2005 Transport Select Committee proceedings.

  2.03  Greenspeed began its campaign when the Government perversely put a maximum speed limit on buses and coaches lower than that for cars. Now, by reducing the maximum speed for cars below that for public transport, the competitive advantage could be transferred to the bus and train that will become the preferred means of travel, thereby reducing GHGs still further, and increasing their profitability without continuous increase in subsidy. Buses are assisted by the reduced congestion and car drivers may also design their lives around shorter car journeys thereby using still less fuel.

  2.04  Inappropriate traffic speeds are the greatest deterrent to walking and cycling. Therefore, the virtuous circle continues to gain pace with the increase in cycling and walking when cars are limited to 20 mph in urban areas and GHGs go down again. When cars are designed for a 55 mph speed limit instead of a 150 mph (for the German autobahn!?) the weight goes down and the efficiency at both 55 and 20 mph increases and GHGs are reduced still further. The labelling system being proposed for cars show the most efficient cars have the lowest maximum speeds.

  2.05  By reducing speed limits in and between urban areas, road congestion and its annual cost of £20 billion will be consigned to history and road pricing (estimated cost of £20 billion) appropriately labelled as a policy of "roads for the rich" will become unnecessary after the pointless wait of 10 years for its introduction. The latest example of road pricing is the M6 Toll which has proved attractive to drivers who average 79 mph thereby consuming about 30% more fuel than if limited to 55 mph. However, if a 55 mph limit had been placed on the M6, all traffic could travel at that speed with little of no congestion and no new road may have been required. This is the intelligent response to the suggestion that the M6 "widening" is to be extended.

  2.06  There will be less noise from engines and tyres both of which will last longer, so that energy is not consumed on repairs and replacements.

  2.07  The very significant savings to the emergency services, to the national health service and to families and communities, by reducing the trauma of road traffic accidents may not directly reduce GHGs. However, these savings can be borne in mind when considering the other economic ad political impacts of lower speeds. It should also be obvious that lowering the national speed limits could be implemented at negligible cost, as a few road signs will need to be replaced.

  2.08  So, if all this is known without eating into the DfT research budget of £40 million, what can it be that prevents the Secretary of State for Transport mentioning speed reduction in the climate change consultation, and continuing to present road pricing as the answer to congestion (regardless of the extra GHG burden? Even with none of the additional benefits, the immediate saving of GHGs arising from road traffic if national speed limits were reduced to 55/20 could be in the region of 25%. In a letter to Greenspeed, Defra's response can be summarised as, "It's the economy stupid!". If that is the reason then it would be very interesting to see the figures. Before a 55 mph speed limit could impose a burden on the economy it would have to exceed the £20 billion wasted through congestion, the subsidy to underused public transport and the savings to the emergency and health services. Access, essential to the economy and well-being, will be improved even if mobility may be reduced. A reference to the Bartlett/Halcrow VIBAT study shows that lower speeds (50mph) is essential to a sustainable transport system and it is only a question of time when this will become inevitable if CO2 targets are to be met. DfT should be concentrating on how and not whether to lower the national speed limits.

  2.09  The DtT are in denial in respect of the magnitude of the current contribution of transport to environmental, social and economic problems that can be attributed to Government transport policy. This is particularly true of CO2 emissions and the growth in car use. The DfT have no answer to these issues.


  3.01  There should be an inquiry into why speed management is not flagged in the recent climate change consultation document as it can be seen to be the measure with the greatest potential for GHG saving at least cost and in the shortest timescale. These comments to the Environmental Audit Committee do no more than set out what is already well known about the unsustainability of the 70/30 mph regime. An integrated and sustainable transport system can only evolve when based on 55/20 mph, where the level of GHGs emitted by fewer, lighter and more efficient vehicles and well used public transport, walking and cycling, would be a small fraction of the levels emitted in the car dependent 1990s and 2000s.

  3.02  The EAC should find that the current DfT policies are not meeting the existing 10 year plan and unless the conclusions of the VIBAT study commissioned from Bartlett/Halcrow are taken on board there is no prospect of the emissions targets being met.

February 2006

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