Economy-energy trade off automation – A decision support system for building design development

Abstract

Building energy simulation is traditionally applied at late phases of the design, when most decisions on specifications of building systems are made. There has been a growing attempt in the literature to enable such simulations at earlier phases of design, when decisions’ impact on the lifecycle behavior is the strongest. While researchers have developed tools/models to support planning and conceptualization phases from this aspect; there have been not much developments for early design development stage (which is usually the scope of semi-detailed cost estimates). This paper introduces a software tool for generating multiple design scenarios and evaluating them, by combining energy simulation and economic analyses, at schematic design and early design development phases of building projects. In this regard, we used state-of-the art of open source technologies, as well as cloud computing, to integrate energy simulation into the alternative selection procedure. The developed system focuses on architectural parameters; lighting power density; and heating, ventilation and air conditioning (HVAC). Analysis of sensitivity of lifecycle energy to such parameters, in a group of representative real-world projects, helped us to limit variations of such parameters, and subsequently their combinations. Using OpenStudio measures and the computational power offered by the cloud, our system generates/simulates all possible design scenarios (combinations of alternative variations for design parameters); and compares them based on building economics performance measures. The workflow is showcased in a case study project, by automatically creating and evaluating 97 design scenarios, based on economic efficiency and liquidity.