A methodology for identifying the influence of design variations on building energy performance

Abstract

In building performance simulation, understanding the potential for parameter variations to cause a disproportionately large change in a performance metric is an important aspect of the modelling and design process. This is especially true if the proposed building is expected to meet a performance target such as net-zero energy consumption. In the context of this paper, variations refer to design modifications which lead to large changes in a performance metric. This paper proposes a methodology to identify influential variations around a performance criterion. This methodology aids in the understanding of possible discrepancies between predicted and realized building performance. A net-zero energy house case-study demonstrates the methodology. A variability analysis of the case-study indicated that combinations of variations caused energy consumption to be larger than on-site generation in 20% of variational scenarios. A back-tracking search identified that 8 of 26 variables were responsible for significant changes in net-energy consumption. In particular, energy-related occupant behaviour, solar orientation, and variables related to the sizing of a roof-based photovoltaic system can significantly influence net-energy consumption. The case-study helped quantify two optimal approaches for passive solar design -one relying on high insulation levels and lower window areas, and the other relying on good insulation levels and large window areas.

A Review of the Regulatory Energy Performance Gap and Its Underlying Causes in Non-domestic Buildings

“…Choices, such as form, orientation, materials, use of renewables, passive strategies, innovative solutions, and others, should be critically addressed during the concept design. Uncertainty and sensitivity analysis that determine the impact of design parameters can guide the design process through identifying and preventing costly design mistakes before they occur (Bucking et al, 2014). The impact of such an issue can be highly dependent on the project team and is likely to influence various aspects of the energy performance of the building.…”

Design optimization and optimal control of grid-connected and standalone nearly/net zero energy buildings

“…In the modeling and designing process of nZEB, understanding the parameter variations that cause large discrepancies between predicted and realized building performance is very important to ensure the target of net-zero energy consumption. Bucking et al [36] proposed a methodology to identify the influential variations on the building performance. A back-tracking search identified that 8 of 26 variables have significant effects on the net-energy consumption in a net-zero energy house case-study, especially solar orientation, variables related to the sizing of a roof-based PV system and energy-related occupant behavior.…”

Uses of dynamic simulation to predict thermal‐energy performance of buildings and districts: a review

“…Therefore, the simulation of building energy performance within dynamic simulation environment is very useful both at early and late design stages since it provides valuable information for architects, engineers, urban planes, contractors, and building owners. Such tool can indeed identify the design parameters which a major impact on the building thermal‐energy behavior, by leading to design choices that reduce the building operational costs and enhance its thermal‐energy performance …”