Design of a building energy system using model-based multi-objective optimization

Abstract:
In addition to an ecological design, an economically optimized design is also important for energy systems in buildings. This is taken as an opportunity to perform a multivariate multi-objective optimization of a building energy system in MATLAB in this contribution. The mean costs and the mean emissions of a building model in TRNSYS were chosen as objective criteria. The optimization variables are the area of a PVT system, the volume of a buffer storage tank and the capacity of a battery storage system. The optimization was performed using the three most used multi-objective optimization algorithms in the literature. This optimization procedure was compared with an optimization according to the weighted sum of the objective criteria in a single-objective optimization. Thereby, the optimization with the multi-objective optimization algorithms could not achieve a better result than the optimization with the weighted sum, but the conflict between both objective criteria could only be highlighted in the multi-objective optimization. This information is not apparent by combining the criteria into one objective function.