Abstract
Digital transformation of metrology is a holistic process that was started formally by the Joint Statement of Intent "On the digital transformation in the international scientific and quality infrastructure" signed by major metrology organisations in March 2022. With the digital transformation of metrology in motion, the questions of a seamless transition to digital representation while ensuring adherence to all the requirements of digital representation and maintaining a sustainable framework for future operations are just some of the challenges faced. To tackle these challenges, also within the concept of "more electrical world" (MEW), one technology is demonstrating high potential applicability as a possible candidate solution-blockchain technology, with its critical underlying properties (e.g., immutability, decentralisation, etc.) being fully compliant with the requirements of digital representation in metrology. Accordingly, this paper presents a blockchain-based concept for the digital transformation of the traceability pyramid for electrical energy measurement. The concept is developed in accordance with the goals of the Metroracle project. Based on the analyzed and presented state-of-the-art, the main contribution of the paper is the comprehensiveness of the concept, which encompasses the whole pyramid and describes all relevant processes and responsibilities of all stakeholders: measurement instrument (MI) owners, certificate issuers (National Accreditation Body (NAB), National laboratory (NL), Reference laboratory (RL)), MI manufacturers/developers, MI installers. The transformed pyramid is defined by Croatian metrology laws and regulations, but with smaller adjustments, it is applicable to other EU countries as well, and also to the traceability of other physical quantities, i.e., not to electrical energy only. Possible legal and technical issues are identified (amount of data, machine-readable standards and regulations, ensuring limited access, legal relevance of digital signature) and corresponding solutions presented, as well as further steps in our research and development within the Metroracle project.