The limits of transport decarbonization under the current growth paradigm

TLDR

Transportation faces technical limits to replacing oil-based fuels, making ambitious GHG reductions difficult. The study aims to assess four global transportation decarbonization strategies for 2050. The authors employ the MEDEAS‑World integrated assessment model for this evaluation. Results show that only a degrowth strategy—rapid shift to lighter electric vehicles, non‑motorized modes, and drastic demand reduction—can meet climate targets; pure electrification alone fails to deliver sufficient GHG cuts, risks mineral scarcity, and is undermined by growth‑driven rebound effects.

Abstract

Achieving ambitious reductions in greenhouse gases (GHG) is particularly challenging for transportation due to the technical limitations of replacing oil-based fuels. We apply the integrated assessment model MEDEAS-World to study four global transportation decarbonization strategies for 2050. The results show that a massive replacement of oil-fueled individual vehicles to electric ones alone cannot deliver GHG reductions consistent with climate stabilization and could result in the scarcity of some key minerals, such as lithium and magnesium. In addition, energy-economy feedbacks within an economic growth system create a rebound effect that counters the benefits of substitution. The only strategy that can achieve the objectives globally follows the Degrowth paradigm, combining a quick and radical shift to lighter electric vehicles and non-motorized modes with a drastic reduction in total transportation demand.