Jacques Combaz

CNRS Research Engineer
VERIMAG Laboratory
Jacques Combaz is a CNRS research engineer at VERIMAG laboratory. He works on the design and the verification of real-time embedded systems using formal methods. In 2018 he joined EcoInfo, a CNRS group addressing environmental and societal impacts of ICT, and he is partially switching his research activities to these topics.
Talk: Rebound effects, a matter of perspective?
Owing to decades of technological innovation, ICT have followed an impressive trend of exponential increase in performance, which is embodied in Moore's and Koomey's laws. Digital technologies are also expected to increase efficiency in other sectors (transportation, building, agriculture, energy, industry, etc.) with, e.g., dematerialization and “smart everything”. Up to now, the continuous optimization of human activities seems to have induce an increase in environmental impacts rather the opposite, by the intensification and diversification of use of technologies. This phenomenon is often presented as the rebound effect: increasing efficiency tends to increase usage, as already observed by W.S. Jevons in 1865 in relation to steam engine efficiency and global coal consumption in the UK. The rebound effect is often described as an economic response to new energy efficient technologies, and is usually quantified based on neoclassical economics. The talk will attempt to explain some of the limitations of this approach and why we need a broader view to deal with rebound effects in the context of the environmental crisis we face.