Design of low-carbon multi-energy systems in the SecMOD framework by combining MILP optimization and life-cycle assessment.

Decarbonizing complex industrial energy systems is an important step to mitigate climate change. Designing the transition of such sector-coupled industrial energy systems to low-carbon designs is challenging since both cost-efficient operation and the reduction of environmental impacts over the whole life cycle need to be considered in the system design. Optimal system designs can be identified using software: Recently, the open-source framework SecMOD was introduced for the linear optimization of multi-energy system models, considering environmental impacts by fully integrating life-cycle assessment. In this work, we extend SecMOD to allow mixed-integer decisions that are vital to model industrial energy systems. Thereby, we provide the first open-source mixed-integer linear program framework with full integration of life-cycle assessment. We use SecMOD to investigate the benefits of a pumped-thermal energy storage system in a sector-coupled industrial energy system and identify trade-offs regarding the system design by comparing the economic and climate optimum.