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2050: four visions for the future

Designing four consistent and contrasting pathways to achieve carbon neutrality in France by 2050: “Transition(s) 2050” is the forward-looking exercise undertaken by ADEME and its partners, linking technical and economic dimensions with societal transformations. Work that can guide future decision-making by exploring the concrete impacts of four major scenarios, each representing societal choices in the key areas of energy and resource consumption.

Scenario 1 - Frugal Generation

In this scenario, the local and durable replace the global and consumable. The transition to frugality results from two levers: constraint and reduced consumption. Ways of moving around, heating, eating, buying and using equipment have changed profoundly, making it possible to achieve carbon neutrality without carbon capture and storage technologies, though with highly developed biological sinks.

Scenario 2 - Regional Cooperation

Changes in societal values have allowed massive investment in efficiency solutions and renewable energy. To achieve carbon neutrality, a gradual change is taking place in the economic system, based on the sharing economy and combining reduced consumption and efficiency. All of this takes place within the framework of shared governance and regional cooperation, making it possible to move forward with pragmatism and maintain societal cohesion.

Scenario 3 - Green Technologies

In this scenario, technological developments make it possible to face environmental challenges through more efficient management. Ways of living, consuming and moving around are very similar to those we know today. Some differences emerge, however, such as less meat consumption, and mobility that is still based on private vehicles, now lighter and electric.

Scenario 4 - Restoration Gamble

Our lifestyles have not changed and rely increasingly on home automation and applications: their proliferation consumes a lot of energy and materials. But this society in 2050 is confident in its ability to manage, even repair, social and ecological systems with the help of material and financial resources. The ecological issues are thus dealt with through technical solutions. A real gamble, as most of these solutions are not yet mature.

Possible paths taken according to the 4 scenarios

Final energy consumption, all sectors


Production of household waste and the like



“All the scenarios reach a comparable end point: neutrality.”

Éric Vidalenc
Deputy director of ADEME in Hauts-de-France

How should these 4 scenarios be approached?

E.V. The goal of carbon neutrality is no longer called into question, even though there is little understanding of the actual implications. How to get there, in contrast, is open for discussion. When we started this work in 2019, we wanted to inform political debate in the run-up to the 2022 elections, and also to contribute to the technical deliberations prior to development of the National Low Carbon Strategy III, planned for 2023. Until then, we had been producing forward-looking work based on ADEME’s vision. This time, we drew inspiration from the four scenarios presented in the IPCC’s 1.5°C report of 2019 and adapted them to the French context. The goal was to see to what extent net zero emissions or carbon neutrality could be achieved through very contrasting strategies.

With Transition(s) 2050, we therefore present the four paths, four gambles to some extent, which are available to us. None is simple, we detail their benefits as well as their limitations, but all reach a comparable end point: neutrality.
However, the carbon emission trajectories for these scenarios are not the same. If we put them into the perspective of the latest IPCC publication of April 2022, which gives three years to act in order to keep warming below 1.5°C, we have to look at 2030 as the transition point, the key date in terms of the goals to be achieved. In the short term, the first two scenarios are more immediately effective, notably through the lever of reduced consumption and the rapid deployment of renewables.

Which aspects is it essential to speed up?

E.V. Unfortunately, there is no easy answer to this question. Our scenarios form coherent wholes. For example, what France is doing with renewable energies – biogas, wind, solar – is starting to have an impact. There is a need to speed up significantly in this area, and notably in biogas. But in scenario 1, there is a massive reduction in meat in the diet, and hence a significant reduction in the size of the livestock population. As a result, there will be a great reduction in the raw material for biogas!

Nevertheless, a few issues do stand out: controlling demand, on the one hand, to significantly reduce consumption. This is the whole point of reduced consumption. Different organisation of mobility, too, with a reduction in the number of journeys made and vehicle electrification, a constant in our scenarios, even though the total number of vehicles can vary twofold from one scenario to another. Finally, construction is a major issue. Production today is not correlated with population growth, it is far too high, notably in relation to the challenges of building on land, and it needs to be reduced. The challenge is to move very quickly towards better use, pooling and renovation of buildings.

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