In the context of climate change and the increasing demand for sustainable solutions in the energy sector, it is of particular interest to consider environmental impacts of alternative energy systems or transformation pathways. In this study, this is achieved by combining an energy system model with a life cycle assessment, enabling the consideration and optimization of factors such as global warming potential, metal depletion potential and land occupation potential in addition to system costs. The individual optimization of these four objectives is extended by a multi-objective optimization using the augmented ε-constraint method. This is applied to the Rhenish Mining Area, a lignite region in Germany that currently undergoes significant structural change, with an electricity system expansion planning for 2040. Depending on the objective, gas-fired power plants or onshore wind energy are strongly preferred. For every objective, the electricity generation in the considered region decreases, especially when environ-mental impacts are minimized, which transforms the Rhenish Mining Area from a current electricity export region to an import region.
Keywords energy system model, life cycle assessment, multi-objective optimization, Rhenish Mining Area, structural change