Parametric tool development for design-integrated energy demand analysis, based on SIA 380/1.

Abstract

It is well known that buildings in combination with the building sector are responsible for 36% of the total energy consumption worldwide and almost 40% of the total direct and indirect CO2 emissions [1]. In Europe the same percentages are respectively approximately 40% and 36%, while 35% of the existing buildings are over fifty years old and 75% of the building stock is energy inefficient [2]. The operational stage of the buildings lasts for decades and thus the assessment of energy analysis during operation is essential.

The greatest potential of creating the optimal design for a building is at the early design stages, where the influence of changes is high whereas their cost is low. The further on the building process continues to higher technical details and even worse to the construction, any change results in smaller impact and higher costs. The analysis of the energy performance of the building should therefore be integrated into the early design phase, but this requires simple tools that could quickly produce results and help with the optimization of the design. However, today’s tools are mostly complex and not design integrated, which can be proven quite time consuming for the architects at this building phase.

The goal of this project is to create a parametric tool for design-integrated assessment of the energy consumption of the building during its operation stage. A parametric tool allows the generation of different variations of the design and thus can be proven a valuable tool in the early stages. SIA 380/1 standard is used as a base for the tool, which uses a static method for the energy demand calculations. This might produce less detailed results than a dynamic model, but it gives faster results which can lower the computation time and power required for an optimization process, which are vital at the early stages. The program is written in Python programming language. In a second step, the developed tool is reformed into a grasshopper component, where it can be directly linked to a 3D model in a more user-friendly environment, with a direct link to the parametric design.

In the first chapter of the presented thesis a general introduction is made for the SIA 380/1:2016 standard which is followed with more detailed description of how the main parameters for the energy calculations are taken into account by the standard. The considered energy balance is presented, as well as the required inputs and assumptions of the given standard.

The parametric tool and the grasshopper component are presented in the second chapter. The required inputs are defined, along with the limitations and the assumptions that were made during their development.

The validation of the tool then is presented in third chapter, first in comparison with the European ISO 52016 standard- with data procured from another thesis-, then in comparison with a dynamic energy calculation tool, with the use of EnergyPlus grasshopper component. Finally, a number of parameters are modified in variations of the base model, to study their effect on the energy demand for the SIA calculation compared to the dynamic tool. These parameters include: the orientation of the model, the glazing ratio, its size, the U-value of the opaque elements and the g-value of the glazing. In general, the static tool of SIA appears to be stricter than the dynamic tool of EnergyPlus and less strict than the European standard.

The thesis concludes with several final observations in the fourth chapter and a discussion for further development in the fifth. The appendix includes additional information and tables from SIA 380/1 and the developed tool.