Comparison of embodied carbon estimating methods

Abstract

The Australian building sector contributes up to 36% of carbon emissions emphasising the importance of carbon management. Embodied Carbon (EC) and Operational Carbon (OC) are classified as two main types of carbon emissions in buildings. Zero carbon projects have gained popularity nowadays where OC is reduced to zero, which enables EC to increase. The focus should have been to reduce overall emissions. The current EC estimating databases and tools could result in inaccurate EC estimates due to various reasons, such as different system boundaries, different geographical locations, lack of standardisation and so forth. To address prevailing shortfalls, a new methodology, Supply Chain based Embodied carbon Estimating Method (SCEEM), has been introduced. This study aims at comparing EC estimates prepared using SCEEM against existing carbon estimating databases/tools. A case study was selected to collect data and estimate EC using SCEEM as well as selected database, Blackbook, and tool, eToolLCD. The results indicated that the EC estimates prepared for the case study was quite high in the selected database/tool compared to the EC values of SCEEM. The percentage difference between SCEEM vs Blackbook and SCEEM vs eToolLCD, was more than 50% for most of the items within the collected data set. The first principles-based methodology considered in SCEEM ensures the accuracy and consistency of estimates prepared using SCEEM.