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The road to greener transport
Research

The road to greener transport

Mobility experts from KU Leuven are looking for ways to make the traffic situation in our country more efficient and sustainable.

11 minutes
08 October 2020

Highways without traffic jams, cities without cars or a public transit network without delays. It may seem like a utopia, but it may be more accessible than we think. Especially if we’re to believe the mobility experts at KU Leuven. They’re looking for ways to make the traffic situation in our country more efficient and sustainable.

In these times of telework, we leave the train, bus or cargo bike for what they are and pay a Skype visit to the virtual Leuven Mobility Research Center (L-Mob). Within that centre, KU Leuven researchers from different fields are looking for answers to mobility questions. L-Mob bundles expertise in infrastructure, logistics, the environment, and more to provide advice to government and industry. How do you organise public transport as optimally as possible? What is the influence of new technology on mobility? Or what about systems such as shared cars or bicycles? These are just a few of the topics that the researchers at L-Mob are examining.

Considerable attention is also paid to sustainability. And when we talk about sustainable mobility, we can’t ignore 'king car'. Many people still take a car, especially for commuting, despite the availability of public transport and the arrival of more and more sustainable means of transport on the market. A necessity or an ingrained habit?

According to professor of engineering sciences Chris Tampère (L-Mob), it may well be a lack of alternatives, but choice behaviour and personal motivation also play a role. ‘That’s what the research has shown,’ he says. ‘Many traffic models try to predict the behaviour of traffic users by gauging efficiency. What’s the duration and cost of a home-work journey by car compared to a public transport or electric bicycle? And what’s the best choice a user can make? But it’s foolish to rely solely on efficiency as a measure. Even if it turns out that the train is faster than the car for a particular journey, that doesn’t mean in practice that someone will just leave their car at home.’

Driving will inevitably become more expensive

Creatures of habit

One of the PhD students under Tampère looked at mobility behaviour not only at one specific moment during rush hour, but for a whole week. What did they find? If someone takes the car 90 percent of the time, they will not abandon when they take one trip, even if it’s less efficient and takes longer. The reverse is true for someone who’s used to taking public transport.

‘We’re creatures of habit,’ says Tampère. ‘You can of course ask yourself whether everyone who lives in an urbanised area needs one or more cars per household. It’s important to understand the basis on which people make choices. One of these is cost. Many people assume that the purchase of a car is a one-off cost, and that afterward you only have to pay for the petrol. They forget that you also have to pay about a thousand euros annually for maintenance, insurance, road taxes, etc. Whilst everyone, on the other hand, is aware of the cost of a train ticket or bus pass.’

Still, driving will inevitably become more expensive, says Tampère. ‘Whether by means of a kilometre charge, a toll system or more expensive parking spaces. Driving is too cheap at the moment and that makes it difficult to discourage it. "Cheap" is then judged on the basis of the limited carrying capacity of, say, city centres, where most motorists are headed. You can only handle so many cars, not only in terms of road capacity, but also in terms of durability. How many trips can you allow from outside the city before that city becomes uninhabitable for city residents?’

One of the sustainable solutions that people are looking at is offering mobility in services, says Tampère. A mobility package that gives you the right to take public transport for a certain amount per month, supplemented with shared bicycles or cars. ‘Maybe in the future that will encourage people to have only one car per family, or to abandon their car altogether. Our research into choice behaviour and that type of service can certainly contribute to the development of such plans, both on the side of the government and the provider.’

Trein MG 2831s station leuven

Train delay

Let's jump back to the present. Is the current public transport network a fully-fledged alternative to a car? ‘There’s a solid alternative for a number of large flows,’ says Professor of Engineering Science Pieter Vansteenwegen (L-Mob). ‘Consider how many people live in Flanders but work in the centre of Brussels. In that case, the train accounts for about half of the commuter traffic. We also have the capacity to increase those percentages. For example, the NMBS is working on the further roll-out of its ‘S’ network, which can provide the wide periphery around various cities with train transport.’

Brussels may be well served, but train delays are commonplace for commuters. ‘It's a story that works in two directions. Noord, Centraal and Zuid are the three most used train stations in Belgium, so if something goes wrong there, it will have consequences for many people. Moreover, the capacity of those stations is filled to brim, so that the slightest disturbance causes other disturbances down the line.’

‘The bottleneck is the zone around Brussels-Centraal where many routes intersect. If a train enters Brussels with a delay of one minute, that can easily be delayed further because it has to wait for other trains to arrive at the platforms or to have priority at an intersection. At the same time, it also slows down subsequent trains.’

One of the solutions from Vansteenwegen's research is to provide more time in the network around Brussels so that trains there can catch up on their delays. ‘The disadvantage is that it takes a little longer as a traveller. But if you have to choose between a twenty-minute commute with the certainty that it really will take that long, or you’re told that it will take 18 minutes but that it will take you twice as long in 50 percent of the cases, the choice is easy to make (laughs).’

The Spine

Public transport is only efficient and sustainable if you can serve enough people, says Vansteenwegen. Flanders is therefore working on the development of a ‘core network’, a kind of backbone between cities that’s served very frequently and at a high quality. This means buses, tram-buses or trams that run about every ten minutes during rush hour, with pleasant seating and that run in their own bed, thereby avoiding traffic jams. ‘So they’re a perfect alternative to the car. Those lines also have to be aligned with train times, and the intention is to also connect additional public transport lines that serve, among other things, the peripheral municipalities or villages.’

Vansteenwegen is also pursuing research into that latter issue. According to him, it’s important that these additional lines are used more flexibly and ‘on demand’ in the future. ‘At the moment, buses still travel a fixed route, but with the advent of smart cities and the “Internet of Things” we’ll have more and more data about the journeys that people want to make at any given time. Knowing that, it would be possible, for example, to have those additional buses make a small detour to pick someone up. Or have a zigzag route from the countryside to the city in the morning, picking up everyone, but driving in a straight line on the way back so that the frequency towards the city can be increased.’

In addition, Vansteenwegen thinks that a large part of the development of public transport is still too geared to current demand, whilst you could steer that demand on the basis of existing supply. ‘That system is called “transit oriented development” and has to do with spatial planning,’ he explains. ‘You could also limit the number of bus stops and focus on a few fixed “hotspots” in addition to the core network. Stops where habitation, shopping centres and relaxation opportunities for people accumulate.’

‘Those few hotspots conflict with the social function of public transport,’ says Tampère. ‘For the most vulnerable people in our society, public transport is the only way to get around. Moreover, they often don’t have the financial capacity to live close to those centres, where house prices are higher. At the same time, if you let bus lines meander infinitely, the bus will never compete with the car. For the social function of public transport, it’s better to supplement an efficient core network with tailor-made transport. Often, on-call buses or variants thereof are looked at, but you could also work with systems of shared cars or "ride sharing".’

MG 2423 autodelen

Cheap houses?

Sustainable alternatives are indeed often focused on the city and peripheral municipalities. What about a village or hamlet where a bus passes once every two hours, or where you have to seek out an on-call bus? Under the current circumstances, doesn’t that make it impossible to make the necessary change in mentality from the car to public transport?

‘It’s important to look at the long term there,’ says Vansteenwegen. ‘You can’t say now that people who want to use public transport should move to the city centre, where living is significantly more expensive. I do think that people should become more aware of where they are going to live and work, and should take more account of the mobility aspect when making those choices. At the moment, for example, there are very few who wonder when buying a home whether the location is easily accessible by public transport, or whether there is a bicycle sharing system nearby ….’

‘If you do, you can often avoid hidden costs’, Tampère adds. ‘A house in the city seems more expensive on paper, but that may not be the case if you account for travel costs by car, or the time you lose on transport every day. Especially if there are additional costs for road pricing, toll systems or more expensive parking spaces. Am I telling everyone to live near a city? Not at all, but the location needs to suit the resident. People who want to enjoy all kinds of activities that you only find on a regular basis in a city might do better to live closer. If that doesn’t happen, we’ll be supporting unsustainable behaviour for the coming decades.’

With company cars you pay people in kilometres. So I prefer to see that system disappear.

Company car

For die-hard motorists, there’s a bright spot on the horizon: the electric car. Here and there you even hear that the electrification of company cars can help introduce the technology to a wider audience. Is there a sustainable solution there?

‘For ten years now, I’ve been advocating for gradually phasing out the company car system and letting it disappear,’ says Van Steenwegen. ‘This greening of the vehicle fleet could perhaps stimulate the introduction of electric cars and meet the need for more charging stations, but there are too many disadvantages. The big problem with company cars is that you pay people in kilometres. You encourage driving, even though it’s already too cheap compared to the social cost, and you’re already stuck in traffic every day. So I prefer to see that system disappear.’

Tampère sees the electric car as we know it as an underutilisation of technology. ‘Our current lifestyle and understanding of mobility has been shaped by the technology of cars with combustion engines. This has created an expectation pattern of long journeys performed within a short period of time. Building an electric car in exactly the same way with a different type of engine has replaced a small part of the old system, whilst we actually have to look for new forms of mobility.’

Sustainability is not just about reducing emissions, according to Tampère and Vansteenwegen. ‘The space occupied by a vehicle also plays a role. Whatever drive technology we use, the individual car as we know it today – a bulky vehicle that achieves high speeds – will eventually no longer be compatible with an urban environment where many vulnerable road users such as cyclists and pedestrians share the road. In that respect, the trend towards larger and heavier cars such as SUVs is of course absolutely not sustainable or conducive to road safety.’

Green future

According to the researchers, the future will be an and/and-story. ‘In cities, we’re more likely to see pedestrians, cyclists and light electric vehicles, supplemented by a highly developed public transport system that transports large amounts of people. In addition, we’ll continue to need a solid road network for trips that you can only make by car. It’s important to keep those "necessary" car trips to a minimum by making smarter choices about where we live or where we establish companies, and by providing sufficient sustainable alternatives. That way you can reduce the pressure on your road system and infrastructure, and mobility becomes a lot "greener".’

Both professors teach in the master of engineering sciences: logistics and traffic, in which the topics covered in this article are widely discussed.