Influences of usage intensity and weather on optimal building energy system design with multiple storage options

Abstract

In non-residential buildings, many factors affect thermal and electrical loads. Some of these factors are not known during the planning process but are essential for a proper energy system design.Conducting a simulation- and optimization-based sensitivity analysis, this study investigates the effects of usage intensity and weather uncertainties on building energy system sizing. We developed a toolchain that comprehensively covers the stages, from determining user-related electricity demand to thermal demand calculation and energy conversion system design, up to deterministic design optimization of storage systems. By means of design of experiments, we systematically applied the toolchain to an all-electric non-residential building as a use case.We find that weather has the strongest correlation with optimal storage sizes and the size of energy conversion systems. They are also affected by the usage intensity of certain building zones. In addition, the storage sizes influence each other in the complex building energy system of our use case. Depending on the scenario and objective, annuities deviate 6%, annual emissions deviate up to 10% from the base scenario.We conclude that normative design methods do not suffice for optimal building energy system design and offer a viable method that can be incorporated into existing planning processes.