With global greenhouse gas emissions reaching record levels every year, the first step in the battle against climate change is accurate and transparent disclosure of carbon emissions. Scope 3 carbon emissions are generally the most significant in a company’s aggregates, so are critical for accurate reporting, but also challenging to measure. This paper evaluates current methods of measuring Scope 3 emissions in supply chains present in literature, for example giving authority to a party in the supply chain to collect secondary data from all the firms, using industry averages or measuring regional or national aggregates. Then, their weaknesses are determined and a blockchain system is recommended as a valuable tool for measuring these emissions. Current literature in the field of integrating blockchain into supply chains and using blockchain to record Scope 3 emissions is surveyed with emphasis on supply chain energy modeling, simulation environments to test the utility of blockchain in this application and combining blockchains with other big data-technologies. A cost–benefit analysis of using blockchain for this purpose is also presented, along with discussing the likelihood of the adoption of this relatively new and evolving technology. Finally, research recommendations describing the efficient implementation of such a blockchain system in supply chains are proposed.