12 February 2021 
Ashley Shelbrooke, HEPA and Project Specialist
To calculate Scope 3 for monitoring and reporting purposes, spend against each Proc HE code is mapped to a defined list of DEFRA categories for which conversion factors - calculating value to carbon - are allocated. This data is then input to the Higher Education Supply Chain Emissions tool (HESCET) in order for a Scope 3 report to be produced. Some institutions undertake this process themselves using the HESCET tool and UK Universities Purchasing Consortia (UKUPC) has also been providing their membership with annual Scope 3 emission reports for a number of years.
Universities use the report in several ways and the content will be useful to procurement, estates, and sustainability teams.
Over the past year, members of the Responsible Procurement Group Scope 3 sub-group, UKUPC, EAUC and HEPA have been coordinating with DEFRA and academics to update the conversion factors used in the HESCET tool.
The conversion factors used had not been updated since 2009. Since then, the materials, methods of production and in some cases logistical methods of delivery have changed drastically. The now updated factors take these changes into account. In 2009, 75 categories were established by DEFRA to break down and map spend levels to in the calculation process; the number of categories has now increased to 311. Additionally, more geographical zones have been included (previously these were simply UK / EU / Rest of World).
Further information regarding year-on-year changes to conversion factors is available here.
APUC have produced a great guide and context information on the Scope 3 emissions data which you can read here.
It should be noted that the updated factors will have an impact of the information provided by the tool when compared to previous years reports.
As at November 2021 the team is working on updating the tool for imminent release.
Institutions will be able to download a copy of the updated HESCET tool here.
HESCET last released in February 2021 at version 3.4.
The updated tool was initially released in January 2021 but a bug was subsequently discovered. The tool was therefore withdrawn, the bug removed, and the fixed tool was released at version 3.4 on 12 February 2021.
The tool is now formally owned by HEPA / BUFDG and as such all updates to calculations can be managed and controlled centrally.
During the update from the 75 DEFRA categories to 311, the categories have shifted from an industrial to a domestic focus. It is recognised that this may not be the best methodology with which to calculate Scope 3 in a University setting. Over the course of the next year the HEPA Responsible Procurement Group Scope 3 sub-group will investigate how other sectors are approaching this challenge, the methodologies used, and how the HESCET tool can be further updated in the future to best meet the needs of members.
