Carbon is not a local transport problem

Carbon emissions and their influence on climate change are now one of the transportation planning community's most important issues. Simon Statham looks into what needs to be done in order to think differently about transport carbon emissions and why they need to be understood in detail if we are to put forward successful strategies to reach net-zero.

Know your problem

I've always believed that to develop solutions to a problem, you need to know the detail of what the problem really is. 

Today's big 'problem' for transport planning to solve is carbon emissions and their impact on climate change. I started looking at this while working at Midlands Connect around 2018. Before that, Midlands Connect only had one core agenda – the economy. 

It seems funny to look only about seven years back when we started work on our original 2017 strategy, but carbon emissions weren't a standalone issue then. If we solved all the other problems, carbon emissions would be dealt with naturally. 

The feeling was that if you've got policies and programmes that target modal shift, particularly in cities where there are lots of short-distance trips to go after with active modes and public transport interventions, then reducing carbon emissions will be a nice by-product of that strategy, won't it? 

How naïve we all were!

When Midlands Connect started to take on the issue, I wanted to properly understand the problem in the lead-up to a planned refresh of our strategy. I knew from national statistics that carbon from domestic transport was around 27% of all UK emissions, over 90% of that came from road-based vehicles, and almost 60% of that was from cars. 

I wasn't satisfied with this; knowing that car journeys were the offender wasn't surprising or helpful. Instead, I wanted to know what types of trips or activities were the key drivers and what policy or interventions would have the most significant impact.

We embarked on a project to paint a detailed picture of where carbon emissions came from.

The outputs of this were stark and startling.

Local car journeys don't burn much fuel

The first and most crucial point is that we cannot assume that significant decarbonisation will be an add-on benefit to traditional local policymaking. Traditionally Local Transport Plans (LTPs) rightly focus on improving the lives of residents by trying to provide a better environment for people to walk/cycle/e-scooter or catch public transport for their everyday trip making. Sometimes this might require a demand-side policy to give the last little nudge, but the theory is certainly sound. After all, we know from National Travel Survey statistics that almost 60% of all car journeys are less than 5 miles in length.

However, these short-distance trips don't burn much petrol or diesel, so they are only a small proportion of where carbon truly comes from. Our estimates showed that trips of less than 5 miles only contribute around 18% of all emissions from cars, which tallied nicely with the National Travel Survey showing that these trips only contribute 15% to all miles driven.

So, our estimates of carbon emissions were backed up by national statistics about how people use their cars.

We may make dozens of trips a week to the shops, school and work; but we also travel to see family and friends in the next town over; or up the motorway to the away match to follow our life-long team; go on a business trip to complete that big sale, or on holiday to the coast or uplands of Britain. Indeed, our research suggested that trips over 25 miles in length contribute 46% of car carbon emissions. 

Added to this issue of the trip lengths of car journeys, there are other aspects that previously LTPs were only focused on activities that generated just a small proportion of emissions. For example, around 15% of emissions come from vans and around a fifth come from heavy goods vehicles (17% nationally but 21% in the Midlands). 

So, if we remove emissions from longer-distance car trips (anything over 10 miles), vans and HGVs, then we found that, in the Midlands at least, the emissions' market' that a traditional LTP might have the most direct influence over, is only around 27%. 

If the plans and policies of an LTP managed to reduce this by as much as, say, 10 to 20% over a 5-to-10-year period, then that would be considered a huge success. But that would mean that well over 90% of all transport carbon emissions would remain.

LTPs are indeed a force for good; they have a huge role to play in improving the lives of residents and enabling them to live more sustainably. LTPs can lead to healthier lifestyles, fantastic places to live, safer streets etc. However, the evidence tells us that even if they are hugely ambitious and ultimately highly successful in what they set out to do, it is still unfair to expect they will be the magic bullet to drop transport carbon emissions dramatically.

So, that's the bad news.

But what can we do about it?

Try to widen the scope of emissions an LTP tries to influence

I've used the word 'traditional' a lot here to describe LTPs.  If the primary objective is to decarbonise, perhaps they ought to be 'Local Transport Decarbonisation Plans', which would give them a much broader scope. For example, Oxfordshire CC and Cambridgeshire & Peterborough CA have been developing 'Local Transport & Connectivity Plans' - recognising the need to incorporate digital and energy/hydrogen networks into transport policy making.

Influence resident and business vehicle choice

It's perhaps obvious to say that we must decarbonise the fleet at an accelerated rate. Local authorities must ask themselves what they can do to influence the take up of zero or ultra-low emissions vehicles. For example, the difference in the pace of electric vehicle charging infrastructure rollout is massive. Some authorities are charging ahead (excuse the pun!) and have ambitious delivery plans. Still, there are many who are more passive and leave the private sector to deliver where the private sector wants to. 

Towns and cities have significant proportions of housing stock with no off-street parking, so the availability of public charging will be vital to support the shift away from petrol and diesel. For example, Coventry now has around 400 publicly available charge points with ambitions for hundreds more, and per head of the population is one of the most densely covered places in the UK. 

In another example, Nottingham City has a scheme running which purchases and leases out (at a reasonable rate!) electric vans to small businesses to help them understand how they can operate without petrol or diesel vehicle. It's an exciting approach, albeit still small at this stage, but it shows the influence councils can have in areas they've not traditionally been active in.

Target longer-distance journeys

Although there has always been a requirement to collaborate across borders, LTPs have tended (rightly) to focus on improving things for residents making relatively short trips.

From the Midlands Connect research, we found that around two-thirds of emissions come from trips which cross at least one boundary (either in/out or through). However, there was a difference between city and shire authorities, where the figure is 75% for more rural areas (influenced heavily by the presence of the strategic road network); but even for cities, around 50% of emissions come from trips which cross their boundary. 

This shows that there is an opportunity for LTPs to widen the scope of emissions they can influence by close working with their neighbours to collaborate on initiatives outside of their boundaries. This is where first and last mile initiatives play a part, particularly accessing and egressing the rail network. There is a decisive role for sub-national transport bodies to play here, but ultimately the initiatives will need to be driven by their inclusion in LTPs.

Behaviour change is vital – on all scales

Our research at Midlands Connect suggested that even using an assumption which accelerated the take up of ultra-low or zero-emission vehicles at a highly ambitious rate (perhaps even slightly on the implausible side!), the decarbonisation trajectory to 2050 was still both too slow and ultimately did not reach zero. Therefore, there is a gap to fill, either extensive (if alternative fuels are not taken up quickly enough) or, at best, one which still requires substantial changes in the way we move and how much we move.

Therefore, local authorities will require comprehensive policies and plans to influence travel behaviour and manage demand for short and, importantly, longer-distance journeys.

Nothing in the DfT's Transport Decarbonisation Plan suggests a national policy is on the horizon. So local authorities may need to fill this gap and consider making potentially tricky political decisions to use fiscal measures to reduce travel demand. 

I am not trying to be evangelical here. We live in the countryside in a two-car household, neither of which is electric (I promise that our next car will be!) and although we work from home when we can, we still drive a lot. But, like a lot of households, we can do more. 

With new thinking, LTPs can do more

Although the evidence tells us that carbon emissions are predominantly not a 'local' transport problem, there are ways that authorities can widen the scope of emissions that their LTPs are trying to influence. 

The first thing to do is to understand the problem properly!

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