Moore's Law and ICT Innovation in the Anthropocene

In information and communication technologies (ICTs), innovation is intrinsically linked to empirical laws of exponential efficiency improvement such as Moore's law. By following these laws, the industry achieved an amazing relative decoupling between the improvement of key performance indicators (KPIs), such as the number of transistors, from physical resource usage such as silicon wafers. Concurrently, digital ICTs came from almost zero greenhouse gas emission (GHG) in the middle of the twentieth century to direct annual carbon footprint of approximately 1400 MT CO2e today. Given the fact that we have to strongly reduce global GHG emissions to limit global warming below 2°C, it is not clear if the simple follow-up of these trends can decrease the direct GHG emissions of the ICT sector on a trajectory compatible with Paris agreement. In this paper, we analyze the recent evolution of energy and carbon footprints from three ICT activity sub-sectors: semiconductor manufacturing, wireless Internet access and datacenter usage. By adopting a Kaya-like decomposition in technology affluence and efficiency factors, we find out that the KPI increase failed to reach an absolute decoupling with respect to total energy consumption because the technology affluence increases more than the efficiency. The same conclusion holds for GHG emissions except for datacenters, where recent investment in renewable energy sources lead to an absolute GHG reduction over the last years, despite a moderate energy increase. We formulate hypotheses for this absence of absolute decoupling from three scientific fields: ecological economics, economics of technology and sociology of technology. We argue that aligning direct GHG emissions of the ICT sector on a trajectory compatible with Paris agreement requires an ecological transition in innovation by adopting sobriety in addition to efficiency.