Optimizing Whole Life Carbon Emissions in Apartment Building

Abstract

As concerns about climate change increase, which can harm the environment, all kinds of businesses face a challenge called sustainability. In the construction sector, one pathway to greater sustainability is designing and constructing buildings with low carbon emissions. Some researchers have explored this challenge by investigating the portion between embodied and operational carbon, as well as the methodologies for calculating each type of carbon emission in buildings. Having an understanding of the design's performance against this challenge will provide more opportunities for design optimization. However, there is limited literature discussing methodologies to optimize whole-life carbon emissions, especially for apartment buildings in the Netherlands. This thesis project aims to fill this research gap by closely examining the practical relationship between embodied and operational carbon and by achieving optimized building designs to minimize whole-life carbon emissions. The scope of this thesis includes analyzing embodied carbon from stages A1 to A5, operational carbon at stage B6, focusing specifically on studio apartments located in the Netherlands. To achieve the aim of this thesis, which is to explore the relationship between embodied and operational carbon in apartment buildings located in the Netherlands, several key steps were undertaken. This study began with a comprehensive literature review and analysis to define factors and methodologies for calculating both embodied and operational carbon emissions. Subsequently, a case study was conducted using a simplified model in Excel and IES software to quantify these emissions. Optimization strategies were then implemented using Rhino 7 and Grasshopper. A detailed framework was developed in Rhino 7 and Grasshopper to guide optimization and analyze the resulting data. Finally, validation and evaluation of the framework and its outcomes were conducted through expert interviews. The findings yielded several critical insights. For instance, certain materials with higher embodied carbon can lead to lower operational carbon, while those with lower embodied carbon may result in higher operational carbon. Moreover, increasing thickness can effectively reduce operational carbon and contribute to overall reductions in whole-life carbon emissions, up to Rc 4; beyond this, the benefits diminish. Furthermore, materials with high embodied carbon above Rc 4 tend to increase whole-life carbon emissions, despite potential reductions in operational carbon. Lastly, each Rc of the façade has its own optimal façade opening, and window frame material only influences a small amount of the embodied carbon and has no influence on operational carbon. However, this result is based on Dutch circumstances and specific MEP inputs. Therefore, these results will differ if different locations and MEP inputs are used. Through this framework, designers are provided with practical guidance to achieve optimal solutions in apartment building design. Additionally, this framework has already been tested by expert respondents in this field, as detailed in Chapter 5. Recommendations for future research include expanding the scope to whole entire apartment (from foundation to roof) and integrating financial considerations into optimization strategies.