LAUSR

Driving the global energy system into a sustainable path has emerged as a major societal concern and policy objective. This transition comes with various challenges and opportunities for a sustainable evolution affecting most of UN's Sustainable Development Goals. We therefore propose broadening the current metrics for sustainability in the energy system modeling field by industrial ecology techniques to account for a conclusive set of indicators. This is pursued by including a life cycle based sustainability assessment into the energy system model considering all relevant products and processes of the global supply chain. We identify three pronounced features: i) low-hanging fruit of impact mitigation requiring manageable economic effort; ii) embodied emissions of renewables cause increasing spatial redistribution of impact from direct, the place of burning fuel, to indirect, location of energy infrastructure production; iii) certain impact categories, in which overall more sustainable systems perform worse than the cost minimal system, require a closer look. In essence, this study makes the case for future energy system modeling to include the increasingly important global supply chain and broaden the metrics of sustainability further than cost and climate change relevant emissions.