טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
Ph.D Thesis
Ph.D StudentPushkar Svetlana
SubjectDesign of Sustainable Buildings - Implementation of Multi-
Objective Optimization
DepartmentDepartment of Civil and Environmental Engineering
Supervisors Professor Rachel Becker
Professor Amnon Katz
Full Thesis textFull thesis text - English Version


Abstract

A methodology for integrating the minimization of the building's impacts on the environment into the targets of the routine building design process was developed.

Simplistic prescriptive tools, such as Leadership in Energy and Environmental Design (LEED) are some practical results of the growing sustainable building research awareness. However, they are based on an arbitrary set of applied credit points to "environmentally friendly" solutions, but are not directly related to quantitative environmental consequences.

In contrast, the methodology devloped, investigated and demonstrated in this research is based on a directly related-to-consequenses quantitative evaluation system. Moreover, in addition to the environmental considerations, multi-objective optimization accounts for the economic aspect as well.

The main hypothesis of this research was: it is possible to group the multitude of building decision variables into smaller clusters in such a manner that environmental optimization can be performed within each group separately, and then, by combining the partial decisions so derived, the overall environmentally optimal solution for the entire building would be obtained.

Thus, the methodology leads to the following three step process: (1) grouping procedure, which is a research based step that ensures that the set of design variables within the group has its largest environmental impact in the certain life cycle stages that constitute that group, and two design stage steps: (2) within group optimization; (3) integration. As a practical outcome of the proposed methodology an Implementation Guide, which is intended to demonstrate the application of the proposed methodology during building design is suggested.

The suggested methodology has been tested and demonstrated for office buildings. Most of the design variables were grouped into three distinct stage-related groups, (Production & Construction Group, Operational Energy Group and Maintenance to Demolition Group), and only a few variables were allocated to the Integrated Group.

Sensitivity analysis indicated that grouping may depend type of fuel used for electricity production, whereas for the same fuel the electricity production technology would probably not alter the grouping. The sensitivity to occupancy type or climate has not been assessed.

As Decision Makers' preferences regarding the design-relevant objective functions (environmental versus cost) can be problematic and subjective, it was decided to apply the non-weighted indifference curves technique for the demonstration of the within group optimization procedures.

The suggested grouping procedure  followed by the relevant within group optimization procedures  ensure that the combined optimal sets lead to an overall optimal environmental solution.