Trustworthy Supply Chain Exchange for Product Carbon Footprint

Product Carbon Footprint (PCF) is a systematic measure of the greenhouse gases (GHG) emissions in creating a product. There are several standards for PCF accounting, but sharing the PCF in a verifiable manner is not standardized. The current processes typically rely on sharing digital documents that assert what is typically an estimated and static PCF. In this paper we present our Trustworthy Supply chain eXchange (TSX) approach and compare different technologies that can be used to implement it. Our approach helps the manufacturers to compute the dynamic PCF of products and enables sharing the PCF with other stakeholders by technically solving the confidentiality concerns which led to estimated and static PCFs in the past. We achieve this with the use of the selective disclosure feature in the verifiable credential (VC) technology provided by the AnonCreds VCs. Moreover, the PCF sharing is integrity protected and establishes the authenticity of the PCF data. We use blockchain as an infrastructure that aids in sharing verifiable PCF across organizations and countries. Lastly, our approach has the flexibility to be adopted for any standard of PCF accounting.