Environmental impacts of the future German energy system from integrated energy systems optimization and dynamic life cycle assessment

Mitigating climate change requires a fundamental transformation of our energy systems. This transformation should not shift burdens to other environmental impacts. Current energy models account for environmental impacts using Life Cycle Inventories (LCIs) that typically rely on historic processes. Thus, the LCIs are static and do not reflect improvements in underlying background processes, e.g., in the energy supply. Dynamic Life Cycle Assessment (LCA) incorporates changes in the LCI and allows for a consistent assessment of future energy systems. We integrate dynamic LCA in a national energy system optimization and discuss the differences between employing static and dynamic LCA in energy system optimization and assessment. Dynamic LCA leads to lower environmental impacts in most categories (e.g., climate change: -18%) and is required for a quantitative environmental assessment. However, our analysis shows that static LCA is sufficient to identify general trends in energy system optimization and assessment for Germany till 2050