Energy performance modelling - Introducing the Building Early-stage Design Optimization Tool (BeDOT)

Abstract

The building stock is responsible for approximately 40% of energy consumption in Europe (Yang, et al., 2014). This has led to directives requiring that buildings perform ever more efficiently regarding energy consumption. In this context, greater is the importance of developing strategies for early design stages, especially improving the communication between architects and engineers. Decisions made early on in design have large impact over the project’s final cost and performance, while design effort is still low. This project introduces the Building Early-stage Design Optimization Tool (BeDOT), a new set of tools for building early-stage design analysis, currently focused on energy performance modelling. It aims at being a broadly flexible and fast-running alternative in the process of decision-making based on building physics. The model, programmed in Python and built upon ISO 13790:2008, has been implemented within Rhino/Grasshopper interface, which opens many possibilities for result visualization and optimization, besides easy geometry editing. BeDOT has been developed focusing on modularity, flexibility, fast processing and on the cooperation of professionals within the same environment. BeDOT has been validated against IDA-ICE for over one thousand cases. Energy results lie within a range of 15% accuracy, with a slight tendency towards underestimation. The process of modelling a standard building from geometry to results usually takes a couple of hours, while calculations are performed in a matter of minutes. BeDOT’s process and accuracy are suitable for early design stages. Further development is needed to improve the handling of data and the program’s user-friendliness.