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Mobility: We Must No Longer Neglect the Factors That Promote Energy Efficiency
Mobility: We Must No Longer Neglect the Factors That Promote Energy Efficiency
Interview with Aurélien Bigo
The war in Ukraine is forcing the European Union to consider a “new European growth model,” one of the priorities of which is reducing its energy dependence on Russia. To this end, several options are under discussion, such as increasing imports from other hydrocarbon-exporting countries, diversifying energy sources, building up gas reserves for next winter, and improving energy efficiency.
However, we must not lose sight of the fact that one of the One of the most effective ways to reduce this dependence is to become more frugal, while consuming less. How does this play out in the transportation sector? Aurélien Bigo, an expert on this topic, answers our questions.
Aurélien Bigo at a glance:
Aurélien Bigo is a researcher specializing in the energy transition in transportation. In 2020, he defended his dissertation on Transportation and the Challenge of the Energy Transition [1]. He then contributed to ADEME’s “Transition(s) 2050” scenarios [2] in the area of transportation. Aurélien is currently a research associate at the Energy and Prosperity Chair.
Q - How would you define moderation?
A - There are several ways to approach sobriety. The key idea is to reduce energy consumption and environmental pressures through behavioral changes, practices, lifestyles, and collective organization and not solely through technological progress.
One way to look at fuel efficiency in transportation is to relate it to the “Kaya equation applied to transportation.”[3].

Simplicity applies well to the first four levers:
- Moderation of demand, for example, by reducing distances through a spatial planning approach that promotes proximity, centered around smaller urban areas, or by reducing the number of long-distance vacations abroad;
- Modal Shift toward modes of transportation that are less energy-intensive and produce fewer carbon emissions, such as active transportation, rail, or river transport;
- The increase in vehicle occupancy rates,for example, with significant potential in the automotive sector through carpooling;
- Energy Efficiency These include reducing traffic speeds and reducing vehicle weight.
The final factor—the carbon intensity of the energy carrier—remains largely a matter of technology.
Another possible approach is to examining simplicity through the lens of action typologies :
- Dimensional Simplicity,for example, by reducing vehicle weight—contrary to the recent trend of cars getting heavier;
- Simplicity of use, such as a reduction in speed or range;
- Collaborative Simplicity,including, among other things, car-sharing and carpooling;
- Organizational Simplicity, such as land-use planning, which shapes mobility patterns, distances, and modes of transportation.
In a way, we could also Define sobriety as the opposite of intoxication, which drives us to go faster and faster, farther and farther, and heavier and heavier.
Finally The contrast between technology and frugality sometimes needs to be qualified, as the two are linked in practice. A new technology such as the electric car will take a different form depending on whether it is intended for more or less fuel-efficient use (battery size, etc.).
Q - Does moderation necessarily involve some form of sacrifice?
A - The concept of moderation remains often associated with sacrifice, but that is not necessarily true. For some levers, the additional benefits of moderation are such that choosing a simpler lifestyle leads to a clear improvement in quality of life, even without taking climate benefits into account. A typical example is partially replacing car use with cycling, which yields both individual and collective benefits: physical activity that promotes health, lower transportation costs, better air quality, reduced noise pollution, conservation of resources and space, resilience, etc. Furthermore, by choosing a more frugal lifestyle, many people can solve acognitive dissonance that they feel between their awareness of the climate emergency and their lifestyles. It is in and of itself a source of well-being, whereas a lack of moderation is said to be a source of unhappiness and frustration.
However To become widespread on a collective scale, moderation requires measures that, at least for some, will be perceived as sacrifices : for example, drastically limiting air travel. To ensure that people embrace a more frugal lifestyle, it is crucial that these transitional measures be developed collaboratively and be socially just.
Q – Simplicity vs. technology: Do we really have a choice?
A - Given that we have fallen significantly behind the goals of the National Low-Carbon Strategy [4], We cannot do without moderation. Trends in recent years show that technological advances have been offset by unsustainable behavior, leading to stable emissions throughout the 2010s—far from the sharp reductions that are needed.
It should be noted that All scenarios that are compatible with carbon neutrality rely heavily on technology (for example: a bet on the rollout of new powertrains) and/or on simplicity (for example: major changes in citizens’ behavior to reduce the distances traveled). In such a context of uncertainty, heIt would be irresponsible to rely solely on one or the other of these dimensions.
The Technology, taken on its own, can also lead to a significant rebound effect unless it is combined with a strategy to moderate energy demand. Furthermore, the government has historically placed far less emphasis on promoting energy conservation than on promoting technology, the There is therefore still a great deal of room to maneuver, and the effects can be felt quickly!
In a nutshell, as France Stratégie and the CGEDD recently noted in a February 2022 publication: “ No neutrality without moderation " [5].
Q – Are you optimistic that moderation will develop in the right direction in the coming years?
A - The situation varies depending on the policy tools, but overall we see a genuine underlying trend in public opinion toward greater moderation, which can be illustrated, for example, by societal changes in the perception of air travel.
ADEME has been conducting surveys for several years followed by a survey of French people's perceptions regarding certain factors. The overall trend is toward greater acceptance of simplicity [6]. However, there are marked differences: some measures are viewed more positively (promoting cycling, public transportation, reducing speed limits in cities, rebalancing urban public spaces, etc.), while others remain less accepted by the public, particularly when they involve restricting certain activities (congestion pricing or carbon taxes, speed limits on highways, etc.). The conditions for implementation and the fair distribution of the burden are also key issues as these studies show. The experience of the Citizens’ Climate Convention has shown that Informed citizens are willing to go to great lengths to live a frugal lifestyle.
So the question is whether these aspirations will translate into policy measures and action,and above all Will it happen at the right pace?
2.
3.
This equation is an adaptation of the Kaya equation, which links world population, GDP per capita, energy intensity of GDP, carbon intensity of energy, and anthropogenic greenhouse gas emissions. These five levers are cited in the National Low-Carbon Strategy and analyzed in terms of their past trends and in prospective scenarios in Aurélien Bigo’s dissertation.
4.
The National Low-Carbon Strategy sets out France's sector-by-sector targets for achieving carbon neutrality by 2050.
6.
For example, 58% of French people believe that we will need to change our lifestyles to address climate change, and 83% of French people would like to live in a society where consumption plays a lesser role (according to (ADEME survey).



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