Even a very rapid switch to electric cars will not reduce greenhouse gas emissions enough. In addition, traffic levels need to be reduced by at least 20%.

Lisa Hopkinson and Lynn Sloman, Transport for Quality of Life01 Feb 2019

Summary

The Intergovernmental Panel on Climate Change has in its recent report identified the significant danger to ecological systems and human wellbeing of allowing global temperatures to increase by 2 degrees compared to pre-industrial levels.

The UK government has responded by asking the Committee on Climate Change to identify what additional effort is needed to reduce emissions above that already agreed through the UK’s Climate Change Act.

Friends of the Earth suggests that the UK should achieve net zero emissions by 2045 at the latest, with a steeper emissions reduction curve before then.

Transport is now the UK’s largest source of greenhouse gases. Friends of the Earth asked the transport consultancy Transport for Quality of Life to produce a series of papers on what changes are needed in transportation and transport policy if the UK is to deliver its fair share of global emissions reduction.

This first paper sets the context for future papers by showing why a switch to electric cars is not enough, and why traffic reduction is also needed.

Transport for Quality of Life suggests that the level of traffic reduction needed by 2030 could be anywhere between 20% and 60%, depending on factors including the speed of the switch to electric vehicles and how fast the electricity powering them is decarbonised.

It also identifies the numerous benefits from traffic reduction, for example to health and wellbeing. It provides a number of important policy recommendations in the final section, which Friends of the Earth is happy to endorse.  

Introduction

This is the first of eight papers commissioned by Friends of the Earth on the transport policies that are needed to cut carbon emissions in line with the Paris Agreement on climate change.

The papers will focus on emissions from cars in urban areas, as this is where significant and rapid carbon savings can be made, while improving quality of life for the 80% of people living in towns and cities1.

Government policy on reducing carbon from cars is mainly focussed on vehicle electrification. While this is essential, the scale and speed of carbon saving that is needed means that electrification is insufficient on its own, and demand management to reduce traffic volumes will also be necessary.

Politicians are nervous of action to reduce traffic because it has (wrongly) come to be seen as ‘anti-motorist’. However, policies to reduce traffic have multiple benefits, and can and should be designed so that there are more winners than losers.

This first paper looks at the shift from fossil fuel to electric cars and argues for a faster transition than currently planned. It also makes the case for action to manage traffic volumes. Future papers will go further into the policy areas that we believe offer the most potential to achieve this2.

In the rest of this paper, section 2 summarises the national and global context for policy on transport and carbon, and section 3 explains the wider benefits of decarbonising transport.

Sections 4-6 explore the three main ways to reduce carbon emissions from the transport sector: improving vehicle and fuel technology, driving more efficiently, and driving less.

Section 7 summarises the high-level policy changes we believe are needed to achieve sufficient emissions savings from the transport sector.

The national and global context

Transport is now the single largest source of greenhouse gas emissions in the UK, accounting for 27% of domestic emissions3. While annual emissions have fallen steadily in some other sectors, notably the power sector, emissions from transport are flat-lining or even increasing.

As Figure 1 shows, emissions from cars account for more than half of domestic transport emissions, with most of the remainder coming from lorries and vans (HGVs and light duty vehicles). Emissions from public transport (rail and bus) account for just 5%4.

A pie-graph showing that the majority of greenhouse gas emissions from transport are from cars Figure 1: UK domestic transport greenhouse gas emissions in 2016

The Committee on Climate Change (CCC) has highlighted the lack of progress in the transport sector, and made clear that without rapid action, the 4th and 5th carbon budgets (covering the periods 2023-27 and 2028-32 respectively) will be missed56.

Under the terms of the Paris Agreement on climate change, the UK is committed to limit global warming to well below 2°C above pre-industrial levels, with an aspirational aim to stay below 1.5°C7.

This is more ambitious than current UK targets and budgets8. A recent Special Report from the Intergovernmental Panel on Climate Change (IPCC) concluded that in order for warming to stay below 1.5°C, human-caused carbon dioxide (CO2) emissions must fall to net zero by around 2050 or preferably earlier910. The IPCC report says that this will require “rapid and far reaching transitions” that are “unprecedented in scale…and imply deep emissions reductions in all sectors”11.

The reductions needed from the UK transport sector in order to stay below 1.5°C are still to be determined by the CCC12.

However, analyses by climate researchers suggest that UK transport carbon emissions will need to be reduced by around 80% by 2030, which is greater than the current CCC target131415.

Global temperature rise is determined by cumulative carbon dioxide emissions, and this means that measures that achieve early emissions cuts offer greater benefits than measures that are implemented later16.

Co-benefits of decarbonising transport

There are three broad ways to reduce carbon (and pollutant) emissions from road transport, in order of decreasing cost-effectiveness17:

  • Demand management: reducing the number of miles driven overall.
  • More efficient driving: using less fossil fuel energy per mile.
  • Making vehicles and fuels less carbon-intensive over their whole life-cycle: by improving vehicle technology and using low or zero carbon energy to power them18.

Failure to stay below 1.5°C of warming will have enormous social and economic costs19. In contrast, the health and economic benefits of fewer and cleaner vehicles are sufficient to justify these policies in their own right, regardless of carbon reduction. The benefits include:

Better air quality: air pollution leads to around 28,000 to 36,000 early deaths per year20 at a cost of £20 billion or more21, and road traffic is a major source of pollution22. Meeting the Climate Change Act targets could cut NO2 and particulate matter (PM2.5) significantly, with significant public health benefits23.

Safer roads: less traffic and lower speeds would reduce road deaths and injuries, estimated to cost society £31 billion a year2425.

Healthier population: more active travel would reduce levels of obesity-related diseases2627. Shifting less than 2% of car miles to walking and cycling has been estimated to provide health benefits worth over £2.5 billion per year in 203028.

Quieter neighbourhoods: less traffic would reduce noise. At low speeds (<20 mph), electric vehicles are quieter than petrol and diesel vehicles29.

More convivial public spaces: demand management would reduce the space needed for parking and multi-lane roads in towns and cities, enabling creation of high-quality public realm.

A fairer transport system: nearly a quarter of households (and nearly half of low income households) don’t have access to a car30. These low-income households would benefit the most from measures to provide affordable good quality alternatives to driving.

Benefits to drivers: less traffic would mean fewer delays from congestion for essential road users. Nearly half of motorists find driving stressful, and more than half would like to reduce their car use, but feel constrained by the lack of alternative ways to meet their transport needs31. An RAC survey found the majority of drivers would swap to public transport if the services were better32.

Making vehicles and fuels less carbon-intensive

More ambitious targets for ULEV and zero-emission vehicles

The government’s strategy to reduce carbon emissions from road transport was set out in Road to Zero, published in July 201833.

It lists 46 actions, of which 44 are intended to change the vehicle fleet from petrol and diesel, first to Ultra Low Emission Vehicles (ULEVs, which include both plug-in hybrid and battery electric vehicles)34, and then to zero emission35.

The strategy sets out the following aims:

  • By 2030, at least 50% (and up to 70%) of new cars and up to 40% of new vans will be ULEVs.
  • By 2040, all new cars and vans will have “significant zero emission capability” and the majority will be 100% “zero emission”.

The main measures to stimulate the purchase of new ULEVs are grants towards the cost of plug-in cars and vans, and reform of vehicle excise duty (VED) for the cleanest vans. There is also investment in electric vehicle charging infrastructure36, and measures to increase use of low-carbon fuels (including hydrogen and biofuels).

The targets and actions outlined in Road to Zero fall significantly short of what the CCC considers to be required6. The CCC has identified a transport policy gap of 14 MtCO2e (million tonnes of CO2 equivalent) for which there are no policies and a further 42 MtCO2e for policies that are either not firm or at risk of delivery6.

This compares with a reduction target of 63 MtCO2e by 2030 for road transport in the 5th carbon budget. In effect, this means that almost 90% of the road transport emission reductions that are required are uncertain and ‘at risk’.

The Chair of the Committee has urged the government “to implement policies with greater ambition to reduce emissions even further”6. This is simply to achieve carbon budgets that predate the Paris Agreement.

The CCC previously recommended 60% of new cars and vans should be ULEV by 203037. Its recent report reiterates the need to end sales of conventional petrol and diesel vehicles by 20356.

A growing number of other countries have set more challenging targets: Norway aims for all new car sales to be ULEV by 202538; and the Netherlands, Denmark, Ireland, Austria, Slovenia, Israel, India and China aim for all new car sales to be ULEV by 2030394037.

Even if all new cars are ULEVs by 2030, transport emissions are still likely to exceed what is needed to meet a 1.5°C target, as we discuss in section 6.1. If the transition is slower than this, more action will be required in other areas – for example, substantial reductions in traffic (possibly unfeasibly large) will become necessary. This means that it is important to make the transition to an electric car fleet as soon as possible.

Policies for a faster transition: subsidy, regulation, or both?

The CCC has called for a number of policies to achieve a faster transition to ULEVs, including grants towards the higher purchase cost of ULEVs beyond 2020, changes to VED and company car tax to make ULEV purchase more attractive, and more ULEV charging infrastructure6. They have also suggested that vehicle manufacturers need to address supply issues and long waiting times.

While all these measures are required, there are risks associated with an approach which focuses mainly on incentives. These risks are exemplified by the Norwegian experience.

Norway is seen as a big success story in encouraging a rapid increase in the purchase of electric cars: ULEVs will account for over 45% of new vehicle sales in Norway in 2018, and at the current growth rate, ULEV market share will reach 100% by 202541.

The rapid take-up of ULEVs is due to attractive incentives, including no import or purchase taxes or VAT, lower company car tax and annual road tax, free parking, no charges on toll roads, and access to bus lanes42. This has made electric cars both cheaper to buy than equivalent conventionally-fuelled vehicles and cheaper to run43.

However, some Norwegian policy experts argue that there is a need for more balance between ‘pull’ measures (ie, incentives) and ‘push’ measures (ie, measures to discourage ownership and use of conventional vehicles).

They point out that the very low cost of electric car use as a result of incentives appears to have encouraged more driving, and less use of public transport and cycling.

One study found that among purchasers of electric cars, public transport-mode share for commuting had fallen from about 23% to less than 6%, while car-mode share had increased from 65% to 83%44.

Modelling suggests that each 1%-point increase in electric car registrations leads to a 0.63% increase in average car kilometres in the short term, and a 0.78% increase in the long run45.

Finally, the availability of electric cars has resulted in an increase in multiple car ownership, such that 15-20% of electric vehicles represent cars that would not have been purchased if there were no electric vehicles on the market46.

These unintended consequences have led experts from a Norwegian government agency to comment:

“If this is the trend that stays in the future transport market, it will produce results that are very adverse for public transport. There is good reason to question whether it is desirable for the urban transport situation and land use in the long term, to maintain these incentives in the form they have today”47.

Norway’s experience offers some important lessons for policy in the UK. It suggests that incentives must be carefully designed so as not to stimulate unwanted increases in vehicle ownership.

One way to achieve this would be for grants only to be offered to purchasers of electric vehicles who are replacing an existing petrol or diesel car or van – in other words, grants should be replaced by trade-in rebates4648.

The rebate should be additional to any trade-in or scrappage discount, and should only continue until electric vehicles reach cost parity with conventional vehicles49.

In parallel, the government should offer the same or higher level of financial support for public transport season tickets, electric car club membership or e-bikes in exchange for scrappage of an old, high-emission car.

Alongside incentives for faster take-up of ULEVs, regulatory measures are needed to ensure sufficient supply of electric vehicles and to progressively reduce the number of conventionally-fuelled vehicles that are sold between now and 203050.

One option is a binding mandate for ULEV sales, similar to that adopted by California but as a percentage (rather than absolute number) of new cars and vans sold51.

This would increase market certainty as well as the prospect of meeting carbon targets52. Manufacturers would be required to sell a fixed percentage of ULEVs, rising steadily to 100% by 2030, with penalties for non-compliance53.

Such a mandate could also specify the split between plug-in hybrid and battery electric vehicles, to encourage a much faster transition to the latter.

This is important because emissions from plug-in hybrids under real-world driving conditions are much poorer than test results suggest5455.

Alternatively, the mandate might be framed as an absolute cap on the number of new petrol or diesel cars and vans that can be sold each year in the UK, falling steadily to zero by 2030.

This would avoid the risk with the ‘percentage approach’ that increased sales of ULEVs would enable manufacturers to also increase sales of conventional vehicles.

While a 100% market share for ULEVs by 2030 is ambitious, it is achievable, as the evidence from Norway shows. In September 2018, 8% of new cars bought in the UK were ULEV56.

A linear trajectory towards 100% by 2030 would require a similar annual growth rate to that in Norway, leading to around 25% of new cars being ULEV by 2020 and 60% by 2025.

Reducing emissions from conventional vehicles

Even if all new car sales are ULEVs in 2030, around 40% of the fleet will still be conventional petrol and diesel vehicles. The CCC has called for more action to reduce emissions from these vehicles, including:

  • More demanding CO2 limits for new cars and vans beyond 2020, with a 50% reduction in new car emission limits between 2021 and 2030 to meet the 5th carbon budget5758.  
  • Introduction of a real-world driving test to avoid cheating by manufacturers59. A new test was introduced this year to replace the previous discredited one, but this is still open to manipulation and does not fully reflect real-world emissions60.  The old test is estimated to have cost British motorists around £21 billion in additional fuel burnt since 200061.  
  • Reintroduction of VED graduated by CO2 emissions6263. Since the VED CO2 differentials were much reduced in 2017, emissions from the average new car sold in the UK have increased for the first time since 19976456. This is partly due to a move away from smaller, lower-CO2 vehicles, with power-hungry SUVs the only segment to record growth in registrations in 201765.  
  • Increases in fuel duty and company car tax.

All of these measures are necessary and important.

More efficient driving

There are immediate opportunities to reduce emissions through more efficient driving, which can benefit all drivers. Although the absolute amount of carbon saved each year is relatively small, it is worthwhile because the cumulative saving over the period from now to 2030 will be significant.

Eco-driving (eg, smooth driving, correct tyre pressure) is estimated to increase fuel efficiency (mpg) by 6% long term and prolongs the range and reduces electricity consumption for battery electric vehicles6667. This could save around 1% of road transport emissions a year with only a small percentage of drivers trained68.

The Road to Zero strategy proposes support for driver training, focusing on novice and fleet drivers. Yet there is evidence that the potential for improvement among average drivers is significant69. Opportunities to increase the use of eco-driving techniques include:

  • Requiring driving instructors to undertake a high quality eco-driving course so they are equipped to teach these techniques to a high standard to learner drivers and other trainees70.  
  • Teaching eco-driving as part of speed awareness courses71. This training could save the average driver over £100 a year at today’s petrol prices72.

Reduced speeds can also help meet carbon targets. The most efficient speed for petrol and diesel cars is around 50 mph and fuel consumption for a typical car increases by around 15% between 60 and 75 mph73.

Nearly half of cars on motorways are exceeding the 70 mph limit74, so simply enforcing the existing speed limit on motorways would reduce annual emissions by an estimated 1.3 MtCO2 in 202075.

This is about 1% of annual road transport emissions. Reducing motorway speed limits would deliver further carbon reductions. Better enforcement or reductions in speed limits would also have benefits for air quality76, noise, congestion and safety77.

Reducing miles driven

How much traffic reduction is needed?

The government’s Road to Zero strategy failed to include any measures to reduce traffic, and the CCC subsequently stated there is an “urgent need for stronger policies to reduce growth in demand for travel”6. Even if there is an early transition to an all-electric vehicle fleet and effective action to reduce emissions from conventional vehicles, it is highly likely we will also need to reduce miles driven by all vehicles.

The scale of traffic reduction required is uncertain until the CCC has modelled the least-cost pathway to a 1.5°C target78. However, provisional work carried out by the Tyndall Centre has found that even if all new cars were ULEVs by 2035 (80% battery electric, 20% plug-in hybrids), a 58% reduction in car mileage between 2016 and 2035 would be needed for car CO2 emissions to be in line with a ‘well below 2°C’ pathway7980.

Assuming transport takes its fair share of emission cuts, a separate study by UCL implies car CO2 emissions would need to be cut to around 17 MtCO2 by 203081. Indicatively, we estimate that this would require reductions in car mileage of around 35-45% between 2017 and 2030 based on the Road to Zero target for uptake of electric cars82. These estimates are highly dependent on a host of factors including the rate of uptake of ULEVs in the car fleet, improvements in conventional car efficiency, size of the fleet, and reductions in grid carbon-intensity, as well as the assumptions used to estimate the carbon budget8384. This means that the necessary mileage reduction could be as low as 20% or as high as 60%.

Based on these two studies, and acknowledging the large uncertainties, we suggest that it is necessary for the government to investigate policy options for traffic reduction in the order of 20-60% between now and 2030. The least-cost pathway would need to be confirmed through detailed modelling by the CCC and others. Traffic reductions of this magnitude may sound an impossible challenge, but to avoid the worst impacts of climate change demands action on this scale. And although the challenge is huge, there are some grounds for believing that substantial reductions in traffic would go with the grain of societal shifts in travel behaviour.

The potential for change

Evidence of changing travel patterns among young people suggests that a shift towards less car-dependent lifestyles is happening already.

For example, the proportions of 17-20 and 21-29 year olds in England who have a driving licence are now nearly 20 and 10%-points lower respectively than in the 1990s85. Car distance travelled by the same age groups is 32% and 14% less respectively than ten years ago86.

As these young adults get older, the amount they drive increases, but there is a general decline in driving across all age groups (with the exception of the over-70s) compared with previous cohorts of the same age87.

There is also evidence of a shift in attitudes, with many young people saying they would never be interested in driving88. There is an opportunity to build on this trend by improving alternative ways of travel, while addressing the difficulties and high costs that many young people without a car experience in accessing jobs and services.

As recently argued by the Commission on Travel Demand, “demand is not just ‘out there’ waiting to be fulfilled or not by policies. It is shaped by policy”89. Instead of the old model of “predict and provide” we need a shift to “decide and provide89.

This means that rather than treating forecast traffic growth as inevitable, and building more road capacity to accommodate it, we should put carbon reduction and other key policy goals, such as public health and fairness, at the heart of transport planning.

This implies a change away from traffic forecasting towards scenario planning, in which policy options to achieve a range of changes in traffic volume are assessed.

The CCC’s 5th carbon budget included small reductions in transport carbon from demand management, based on shifting 5% or 10% of personal mileage to bus, walking and cycling by 203090.

The CCC partly based these reductions on the evidence from past behaviour-change programmes such as Sustainable Travel Towns and the Local Sustainable Transport Fund.

Yet these programmes, while positive, were short-term and limited in what they could do, involved little or no traffic restraint, and had funding levels that were a fraction of investment in road-building91.

Large cuts in vehicle mileage will need much more funding, major improvements in public transport and provision for walking and cycling, effective traffic restraint policies, and a consistent long-term approach. 

While a large proportion of car journeys are short distance (<5 miles), these represent less than one-fifth of carbon emissions (19% – see Figure 2). More than half (57%) of carbon emissions from cars are from short-to-medium length journeys (under 25 miles)92. Significant mileage and carbon reduction requires these medium length journeys to be targeted too.

Many car journeys under 10 miles (the average car commute distance) should be possible to switch to alternatives, particularly in urban areas. The percentage of car commuters who could switch to other modes increases with city size93.

This explains why the biggest reductions in car mileage in recent years have been in London, core cities and conurbations, and other large towns94.

Yet regardless of whether they live in urban or rural areas, more than half of people report that they have alternatives (public transport, walking, cycling or other) to get to work95.

Switching longer journeys of 10-25 miles will be more challenging and will need a package of carrots and sticks involving land-use planning, improved public transport and restraints on car travel9697.

In particular, changes in land use have the potential to reduce journey lengths, replacing medium-length car trips with short trips by public transport or cycling.

A pie-graph showing over a third of emissions from driving are for journeys under 10 miles Figure 2: Estimated CO2 emissions from cars by journey distance

Counterproductive policies and forecasts

Despite the potential for change, UK transport policy is heading in the wrong direction. One recent analysis suggests the freeze on fuel duty since 2001 has directly caused a 4% growth in traffic, emission of an additional 4.5 million tonnes of CO2 and increased emissions of health-damaging pollutants such as NOx and PM1098. The freeze is set to continue for a ninth year in a row. Although average car mileage per person has fallen99, the number of vehicles has increased over the last ten years, and as noted earlier, abolition of graduated VED has encouraged a shift to purchase of larger less-efficient vehicles. The growth in traffic and the shift to larger vehicles has cancelled out the effect of any improvements in vehicle fuel efficiency. 

The government forecasts that traffic in England and Wales will increase by up to 51% between 2015 and 2050 in a ‘high electric vehicle’ scenario100. Light goods vehicle (LGV) traffic has grown by nearly 70% over the last 20 years, and is forecast to more than double by 2050100101. None of the government’s forecast scenarios are compatible with the carbon emission reductions in the 5th carbon budget, let alone the more stringent Paris Agreement needs102.

Government forecasts consistently overestimate traffic growth, and so in practice it is likely that actual growth will be less than predicted. However, high forecasts lead to a systematic overestimation of the ‘benefits’ of new road construction103. This in turn leads to more road building, which generates more traffic104105. The policy bias towards road building and underfunding of alternatives have the effect of increasing car-dependency, with people forced to drive in order to access employment and services106. The National Infrastructure Commission has called for more investment in mass rapid transit in recognition that new roads only lead to new car journeys107.

Planned funding for the trunk road network of £30 billion is the highest ever, of which £1 billion will go towards the creation of a Major Road Network108. This high funding for more road capacity will drive emissions higher, making it more difficult to achieve future carbon budgets. We therefore believe that all new road construction should be halted immediately, and not resumed unless and until it can be demonstrated that transport carbon emissions are safely below the level consistent with a 1.5°C limit. Money no longer required for road schemes should be invested in sustainable transport infrastructure and services.

Conclusions

In addition to implementing the priority actions identified by the CCC in their 2018 Progress Report and response to Road to Zero, the following are ‘must do’ actions to get transport on a 1.5°C track:

  • Regulate the number of new fossil fuel cars and vans that can be sold, so that by 2030 all new car and van sales will be ULEVs, and nearly all will be zero-emission battery electric vehicles.
  • Reform the grant scheme for electric cars to a trade-in rebate system, with grants only for trading in or scrapping an existing vehicle.
  • Offer similar or higher financial support for electric car clubs, public transport or e-bikes in exchange for scrappage of an old, high-emission car.
  • Develop and assess policy scenarios to reduce car mileage by 20-60% between now and 2030.
  • Cancel all new road schemes and use the funding for public transport, walking and cycling.
  • Enforce speed limits and consider further measures, including speed limit reduction, if scenario planning shows additional carbon savings are needed.

The transport sector is lagging in terms of carbon reductions and more action is needed beyond the measures set out in the 5th carbon budget. The IPCC has set out the scale and urgency of the challenge. To limit global temperature rise to 1.5°C will need deep emission cuts from all sectors as quickly as possible. The government should ask the CCC to determine the additional sector reductions that are needed between now and 2032, not just after 2032.

It is likely that transport carbon emissions will need to be reduced by around 80% by 2030. To achieve this we need to electrify the car and van fleet as soon as possible. This cannot be achieved through incentives alone, and will also require regulation to limit sales of conventional cars and vans, and increase sales of electric cars and vans, between now and 2030. Incentives to encourage purchase of electric vehicles must be designed to avoid increasing car ownership. One way of doing this would be to replace the current grants for electric vehicles with a trade-in rebate scheme.

Even if all new cars and vans are zero-emission by 2030, which will reduce emissions significantly, it will still be necessary to reduce miles driven. The scale of traffic reduction required may be in the order of 20-60% by 2030, depending upon the implementation of other policy measures. We therefore need to develop and assess policy scenarios that could achieve large reductions in traffic volume.

There is significant scope to shift car journeys (and mileage) to other modes. There is most potential for change in urban areas, but we will need to reduce traffic elsewhere too. The current focus of transport policy on building new roads will make matters worse, because it will increase car dependency and traffic. The government should therefore cancel all new road construction until transport carbon emissions are in line with carbon budgets, and use the money to invest in sustainable transport infrastructure and services. This will not only help us work towards net zero emissions by 2050, but will also result in better air quality, safer roads, healthier lifestyles and more vibrant and convivial towns and cities. How we do this will be outlined in future papers.

Acknowledgements

The authors (Lisa Hopkinson & Lynn Sloman from Transport for Quality of Life) would like to thank the following for help with information for this paper (in alphabetical order):

Kevin Anderson (Tyndall Centre for Climate Research, University of Manchester); Keith Budden (Cenex); Tom Callow (Chargemaster); Ellie Davies (Committee on Climate Change); Rachel Freeman (formerly Tyndall Centre for Climate Research, University of Manchester); Ewa Kmietowicz (Committee on Climate Change); James Price (UCL Energy Institute, UCL) and Steve Pye (UCL Energy Institute, UCL).

The findings in this paper do not necessarily represent the views of those listed above.

We would also like to thank Mike Childs, Chris Crean and other Friends of the Earth staff and activists for their helpful advice and comments.

 

A PDF version of this briefing, with full references and hyperlinks, is available on the Transport for Quality of Life website.