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# 3 Is your journey really necessary?

The UK population has grown by about 30% since the early 1950s but transport energy demand has increased nearly fourfold. This growth is particularly a product of increased car travel, as shown in Figure 5.

Figure 5: UK passenger transport by mode, 1952–2018

Reducing transport energy use raises a number of questions. The first is: ‘Is your journey really necessary?’ The ultimate energy service of transport is mobility; however, this is not quite the same as physical transportation.

Modern telecommunications offer a form of mobility. The Covid-19 pandemic severely limited the movement of people throughout 2020 and 2021. Lock-downs in many countries have changed patterns of energy use, with large numbers of people working from home. This resulted in large reductions in transport energy use, particularly aviation, and global oil consumption in 2020 was down 8% from its 2019 level. It has been replaced, in part, by extensive use of home working, reducing the amount of physical commuting, and by tele-conferencing over the Internet. It is difficult to say how much of the ‘physical transport habit’ has been permanently broken. In the UK, final transport energy use in 2023 was 7% down on its pre-COVID level in 2019. It is still possible that the world could return to its previous ‘business as usual’ state.

The next question is ‘Can your journey be done in a less energy (and CO2) intensive manner?’ Figure 6 compares the CO2 emissions of different modes of transport, both within the UK and for short international journeys to and from it. They vary enormously in their emissions per passenger-kilometre travelled. Air travel, for example, is both energy and CO2 intensive. International rail travel, between the UK and France through the Channel Tunnel, has the advantage of being both energy efficient and able to use low-carbon electricity.

Figure 6: CO2 emissions of different modes of UK transport

One social method to reduce the energy and CO2 intensity of travel is modal shift, i.e. moving journeys away from the energy-intensive modes and towards the more energy-frugal ones.

For policy purposes, modes of transport can be ranked in a hierarchy, with walking and cycling at the top and air travel at the bottom (see Figure 7).

Figure 7: The low carbon hierarchy of transport modes

For example, if a greater proportion of long-distance journeys within Europe were made by inter-city train rather than by air, the overall energy demand involved could be reduced substantially. In Sweden, an ‘anti-flying’ movement has arisen that has coined the word ‘flygskam’ (flying shame). Those who successfully shift to carrying out their journeys by train can indulge in a certain amount of ‘tågskryt’ (train bragging).

One particular target for improvement is the urban commuter who drives to work. The energy intensity could be significantly improved by making sure that cars contain more than just one person. Even better, the journey could be made by rail, bus or cycling.

The final question is, perhaps: ‘Does suburbia have a future?’ It may be necessary to create (and recreate) cities where it is not necessary to use a car to reach shops or schools, and they can be reached by walking or cycling.

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