Julien Dubois

Work in Progress

• Transitioning Away from Fossil Fuels: Evidence from a Growth Model with Putty-Clay Capital

Show Abstract

This paper proposes a theory to disentangle input-saving technological progress from technical efficiency gains of capital. Assuming different vintages of capital, each defined by fixed input requirements, I derive the optimal allocation of a scarce resource – namely energy – over time. Qualitatively, reduced capital flexibility creates path dependence, slowing down the transition away from fossil fuels. Quantitatively, a calibrated version of the model suggests that standard frameworks may underestimate both the duration of the transition and the welfare implications along the adjustment path.

Presented at the poster session of Clifirium 2025 at Banque de France. Poster here.