Fiches info

Energy return on investment (EROI) is a biophysical and ecological economics concept that is useful to think about how organisms, ecosystems and societies must obtain enough surplus energy returned from energy gathering activities to live, reproduce, and thrive. EROI can help us overcome the false dualism between nature and society. EROI is a useful metric for economics because it is based on immutable physical laws rather than sometimes arbitrary human preferences. It is essential for assessing useful power, energy trade-offs, efficiencies (and inefficiencies), resource depletion trends, resource quality, and surplus potentials of different fuels and technologies that power, or might power, our socio-economic systems. Apparent inconsistencies in the literature can generally be reduced or eliminated by paying careful attention and explicitly stating boundaries and definitions. We argue that proper use of EROI is critical to understand the interconnections among the environment, energy, and socio-economic deve

A novel methodology is developed to dynamically assess the energy and material investments required over time to achieve the transition from fossil fuels to renewable energy sources in the electricity sector. The obtained results indicate that a fast transition achieving a 100% renewable electric system globally by 2060 consistent with the Green Growth narrative could decrease the EROI of the energy system from current ~12:1 to ~3:1 by the mid-century, stabilizing thereafter at ~5:1. These EROI levels are well below the thresholds identified in the literature required to sustain industrial complex societies. Moreover, this transition could drive a substantial re-materialization of the economy, exacerbating risk availability in the future for some minerals. Hence, the results obtained put into question the consistence and viability of the Green Growth narrative.