The Transport Decarbonisation Plan is here, but how best to deliver it locally?

Effective transport decarbonisation requires action across technology and behaviour change and, crucially, by local authorities in preparing net zero strategies. How should they go about it, asks Tony Meehan

The DfT published Decarbonising Transport: A Better, Greener Britain – the Transport Decarbonisation Plan (TDP) – in July this year. Publication of the latest scientific evidence by the Intergovernmental Panel on Climate Change (IPCC)1 starkly emphasises the urgent need for decarbonisation – globally and across all sectors. 

It is unequivocal that human influence has warmed the atmosphere and that widespread and rapid changes in climate have occurred. We will exceed global warming of 1.5 degrees Celsius within the next two decades, intensifying irreversible changes, if we do not tackle carbon emissions rapidly. 

Will TDP deliver net zero?’

The media and transport sector response to the TDP has mainly focused on the plan’s insufficient ambition and whether its implementation will enable us to hit the targets for emissions reductions from domestic surface transport recommended by the Climate Change Committee (CCC) in its 6th Carbon Budget. 

The TDP argues, though without presenting forecasts in detail, that the plan provides a credible pathway for emissions from domestic transport to get to zero carbon by 20502. However, it is less clear whether it aligns with the steep decarbonisation pathway to 2050 identified in the 6th Carbon Budget.  

Hitting the 6th Carbon Budget’s target for domestic surface transport – reducing emissions from 113 million tonnes of carbon dioxide equivalent (MtCO2e) per annum in 2019 to 32 MtCO2e in 20353, a 72% reduction - is a significant challenge but not impossible.  

So, how does the TDP help us follow the pathway? 

Recognising uncertainty

Across the transport sector, we have become conditioned to reducing future transport problems to an extrapolation of where we are now, and where we have been for 20, 30, 40, 50 years – maybe longer. We also tend to assume that travel demand will grow; that technology improves incrementally; that we can base our decisions on what has worked well in the past; and, that people change their behaviours slowly, if at all.  

But the years ahead will be different, and the TDP recognises these uncertainties in the pathway to achieving the 6th Carbon Budget targets and ultimately net zero.  

The most crucial uncertainty is the speed of transition to zero emission road vehicles. This will have, by far, the most impact on domestic transport emissions of any change to the transport system, providing it is supported with clean electricity. The Government has already committed to phasing out the sale of petrol and diesel cars and vans by 2030, and the CCC’s assumption in the 6th Carbon Budget Balanced Net Zero Pathway is that the UK car stock will comprise 25 million Battery Electric Vehicles (BEVs) by 20354 – nearly 65% of the total car fleet. Although the TDP does not present its own forecast, it cites a lower figure for BEVs in 2035 of 46% taken from industry body estimates5. 

This range of forecasts illustrates one of the TDP’s challenges. There are many unknowns about the transition to zero emission vehicles, including the response of car buyers and how travel patterns evolve post-Covid. 

Uncertainties also include the response of vehicle manufacturers; the evolution of affordable BEVs and the cost of operating the vehicles; the rise of new models of vehicle ownership and shared mobility; and the speed of technology development that will enable zero or low emission freight movement. While the technology for transitioning to electric cars and vans exists today, subject to questions of scale and pace of change, for heavy goods vehicles, it is still in development.

The TDP sets out a framework for supporting this transition – including new regulatory proposals and the previous commitments to tax incentives for switching to zero-emission vehicles and funding for charging infrastructure. But it also states that, dependent upon progress, there may be a need for additional ‘targeted action’. Almost certainly, we will require more intensive measures than those currently in the plan to move to a zero emission fleet aligned to the 6th Carbon Budget. 

Reduce demand, change behaviours

An antidote to uncertainty is to look at the existing set of tools that we can use to decarbonise transport. These tools don’t involve massive technology risks; they are potentially quick to implement and can help deliver decarbonisation quickly. They are local transport schemes that will span all modes of transport; schemes that can encourage greater use of active travel and public transport and less car use.  

A crucial part of the 6th Carbon Budget net zero pathway is the role of reducing demand for road travel. And, broadly, this means shifting to zero emission, high occupancy modes, travelling less often or shorter distances, or not travelling at all. This is not new in the sustainable travel world – but the scale of the shift needed to deliver decarbonisation is significant.

Translating political declarations into tangible outcomes will require local empowerment, funding and strong support from stakeholders and citizens to deliver change

The CCC’s Balanced Net Zero Pathway targets a 9% reduction in car mileage by 2035 compared with the baseline, resulting from mode shift, increased car occupancy and more working from home. It also assumes reductions of 3% in van mileage through urban consolidation and 10% in HGV mileage through greater efficiencies in logistics. Recent work that Atkins has undertaken for local authorities shows that this is possible, but it requires sustained political commitment to deprioritise car travel (e.g. reallocating roadspace for cyclists and buses, parking demand management), new ways of thinking and coordinated bold action.   

The TDP reinforces the need for behaviour change – primarily through place-based action. It also highlights the importance of developing measures that coordinate spatial planning and digitalisation with transport planning. This will provide accessibility that is shaped to meet very specific local needs and deliver wider benefits alongside decarbonisation. Drawing on work by Atkins for metropolitan and urban/rural authorities, it is clear that we can take many actions right now to enable the delivery of rapid decarbonisation of local journeys in the 2020s. 

As widely reported, 74% of local authorities across the UK have declared climate emergencies6. But translating political declarations into tangible outcomes will require local empowerment, funding and strong support from stakeholders and citizens to deliver change. In principle, the TDP supports this, with a promised transformation of local transport funding in England and delivery of a toolkit to support the implementation of decarbonisation measures. 

Time to shift delivery

The TDP doesn’t commit to many new measures or any new funding but, for the first time, we have a cohesive framework setting out the requirements to decarbonise transport that looks across all modes of transport, addresses supply and demand, and recognises the need to integrate transport measures with other fields such as spatial planning and the energy sector. 

It provides clarity of intent on delivering zero emissions fleets across all modes including tackling the challenge of freight. It also provides clarity on the need for action across technology and behaviour change. And, crucially, it identifies the key role of local government in tailoring decarbonisation actions to the specific needs of local areas and contexts.

The plan has been over a year in preparation, but it has set out the complex range of policy tools and delivery priorities needed to decarbonise transport. It’s difficult to see how the delivery of the measures and funding as currently defined will achieve the 6th Carbon Budget 2035 target – but in principle the plan provides the framework to dial up the level of action likely to be needed. We also wait to see how the Government’s Net Zero Strategy, due for release ahead of COP26 in November, takes account of the TDP and integrates Net Zero into wider policymaking and investment priorities.  

But, overall, the fact remains that we have a transport decarbonisation plan. The immediate challenge is now one of shifting rapidly to delivery, as time is of the essence.

Tony Meehan is the practice director for Net Zero transport in Atkins

1. IPCC, 2021: Summary for Policymakers. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change.
2. However, combining domestic and the UK’s share of international air and maritime emissions, the TDP’s trajectory does not achieve zero carbon by 2050, and this will require the transport emissions to be offset by negative emissions elsewhere across the economy.
3. For the Balanced Pathway, Committee for Climate Change, Sixth Carbon Budget, December 2020
4. Committee for Climate Change, Sixth Carbon Budget, December 2020, p98
5. Transport Decarbonisation Plan, p29
6. Climate Emergency UK (2021) https://www.climateemergency.uk/blog/list-of-councils/