Whether renewable energy sources (RES) will provide sufficient energy surplus to entirely power complex modern societies is under discussion. We contribute to this debate by estimating the current global average energy return on energy invested (EROI) for the five RES technologies with the highest potential of electricity generation from the comprehensive and internally consistent estimations of their material requirements at three distinct energy system boundaries: standard farm-gate (EROI_st), final at consumer point-of-use (EROI_final), and extended (including indirect investments, EROI_ext). EROI_st levels found fall within the respective literature ranges. Expanding the boundaries closer to the system level, we find that only large hydroelectricity would currently have a high EROI_ext ~ 6.5:1, while the rest of variable RES would be below 3:1: onshore wind (2.9:1), offshore wind (2.3:1), solar Photovoltaic (PV) (1.8:1), and solar Concentrated Solar Power (CSP) (<1:1). These results indicate that, very likely, the global average EROI_ext levels of variable RES are currently below those of fossil fuel-fired electricity. It remains unknown if technological improvements will be able to compensate for factors, which will become increasingly important as the variable RES scale-up. Hence, without dynamically accounting for the evolution of the EROI of the system, the viability of sustainable energy systems cannot be ensured, especially for modern societies pursuing continuous economic growth.

Electric vehicles are characterized by low energy stored on energy invested (ESOI) levels and their spread will worsen the criticality of some minerals.

Ilya Prigogine's trinomial concept is, he argued, applicable to many complex dissipative systems, from physics to biology and even to social systems. For Prigogine, this trinomial— functions , structure , fluctuations —was intended to capture the feedback-rich relations between upper and lower levels in these systems. The main novelty of his vision was his view of causation, in which the causal arrow runs downward from dissipative structures to their components or functions. Following this insight, some physicists and biophysicists are beginning to apply terms formerly used mainly in biology, such as evolution , adaptation , learning , and life-like behavior , to physical and chemical nonequilibrium systems. Here, instead, we apply Prigogine's view to biology, in particular to evolution, and especially the major transitions in evolution (MTE), arguing that at least the hierarchical transitions—the transitions in individuality—follow a trajectory anticipated by the trinomial. In this trajectory, formerly free-living organisms are transformed into “functions” within a larger organic “structure.” The Prigogine view also predicts that, consistent with available data, the increase in number of hierarchical levels in organisms should accelerate over time. Finally, it predicts that, on geological timescales, ecosystems and Gaia in particular will tend to “de-Darwinize” or “machinify” their component organisms.

Las fuentes de energía no renovables (fósiles y nucleares) están doblemente limitadas, tanto por su finitud como por los perjuicios ecológicos y sociales que causan. Las fuentes de energía renovable tienen flujos en la biosfera muy grandes, sin embargo, los sistemas tecnológicos que las captan no son renovables y por tanto tienen limitaciones tecnológicas, ecológicas y sociales también. Aunque una buena parte de la literatura científica ha venido estimando que estos factores limitantes son pequeños frente a los políticos y económicos, aquí se muestra que esta literatura ha venido sobreestimando la capacidad tecno-sostenible obtenible a lo largo del presente siglo, en buena medida por un tecno-optimismo implícito y una falta de pensamiento sistémico. Este potencial podría ser del orden de entre la mitad y la cuarta parte del uso actual de energía, lo que apunta, dada la necesaria transición hacia fuentes renovables por problemas ambientales, a un fuerte decrecimiento de la matriz energética que sostiene nuestras sociedades a escala global.

Net energy analysis (NEA) has traditionally focused on static, facility-level assessments or dynamic, empirical sectoral assessments of past developments. However, energy transitions are inherently dynamic, future-oriented processes that involve entire energy systems, including both generation and supporting infrastructure. Addressing this gap requires advancing simulation tools such as energy system models (ESMs) and integrated assessment models (IAMs) into frameworks capable of fully dynamic NEA computation. The MEDEAS-World model introduces a novel methodology for dynamically assessing the energy and material requirements of transitioning the electricity sector from fossil fuels to renewable energy systems (RES). Simulating two scenarios with different levels of RES penetration by 2060 under a green growth paradigm, we identify two key findings: (1) the shift to RES may drive economic re-materialization, potentially offsetting efficiency gains, and (2) complex interactions arise between RES expansion, variability management, innovation, and mitigation, producing a climate action-system viability trade-off. The transient system-wide energy return on investment (EROI) values below 5:1 further call into question the feasibility of the green growth paradigm. These results underscore the need for dynamic NEA to inform robust climate mitigation strategies. <!----> <!----> <!----> <!---->