Comparison of Methods for Calculating Indirect Upstream Carbon Emissions from Information and Communication Technology Manufacturing

The use of Information Communication technology (ICT) is rapidly increasing in an age of digitalization. Measurement of carbon dioxide equivalent (CO2e) emissions from ICT is crucial for reducing them. Most ICT organizations focus on Scope 1 and 2 emissions as they have greater control over them, commonly ignoring Scope 3 emissions. Scope 3 Category 1 (S3C1) emissions occur throughout the raw material acquisition and manufacturing stages of an ICT product's life cycle accounting for a large portion of the sector's overall CO2e emissions and energy consumption. By not reporting Scope 3 emissions, companies lose the ability to reduce their overall CO2e corporate emissions. Although Category 1 and 11 under Scope 3 account for 85% of ICT's worldwide CO2e emissions, the methodologies for calculating S3C1 emissions in ICT are understudied. This study focuses on these emissions in the framework of Sustainable Development Goals 9, 12, and 13. Product life cycle assessment (PLCA) and Spend-based methods have been used to analyze S3C1 emissions in the ICT sector with two case examples of laptop computers and smartphones. The Excel Management Life Cycle Assessment (EMLCA) tool has been used for the S3C1 emissions estimation. PLCA and Spend-based methods are compared on their ability to calculate CO2e emissions. It is concluded that the Spend-based is faster than PLCA for predicting ICT emissions with modest uncertainty for smartphone and laptop components. Furthermore, this work explores the advantages and downsides of both methods.