Materials-based inconsistencies in a life cycle assessment database on digital services

Abstract

The NégaOctet consortium developed the very first database to assess the environmental impacts of digital services through life cycle assessment (LCA). A digital service regroups three third: the data centres, the networks and the end-user terminals. Around 1 500 data, specific to France and Europe, were created during the project.

In a digital service, the extraction and manufacturing of end-user terminals and data centres are the most polluting life cycle steps. The wafers are responsible for these impacts, requiring highly pure materials and power-consuming processes. Therefore, this thesis aims to identify the most critical material-based inconsistencies and correct them before the publication of the NegaOctet database.

An LCA on a cloud service was done to manipulate the database and investigate inconsistencies. The indicators from the PEF methodology have been selected. The LCA was carried out on EIME software. As a result, the data centre is the most impacting third. It impacts from 12% to 77%, depending on the indicators. In addition, nine issues were found in the database.

The most critical one concerned allocating the digital services’ equipment. An experiment has shown that using the wrong allocation can double the impacts of a specific equipment. This thesis determined allocation equations for the terminal’s equipment, the network, and the data centre equipment. In the end, three equations were found for the servers depending on the data available by the user. A ratio of equipment per server was selected, for the firewall and switch. The non-IT equipment and architecture allocation was determined from the ratio of IT room m² per server. Equations were also determined for the terminals, network and storage bay.