Sustainability assessment of blockchain systems in timber supply chains: environmental and economic impacts

This study quantifies the energy use, carbon dioxide equivalent (CO 2 e) emissions, and transaction-related costs of distributed ledger technologies (DLTs) in the context of timber traceability. It combines: (i) a PRISMA-guided systematic review of empirical studies on DLT energy consumption; and (ii) benchmark values derived from continuously updated online monitoring sources, captured at defined access dates and fully documented in the . Comparable metrics are reported at the level of individual traceability events (kWh/tx, gCO 2 e/tx, and USD/tx) and are related to a realistic timber supply chain transaction model that was empirically validated in a pilot study. The results reveal substantial differences in sustainability performance across consensus mechanisms. Proof-of-Work (PoW) networks exhibit prohibitively high energy demand and CO 2 e emissions for frequent traceability notarizations. In contrast, Proof-of-Stake (PoS), PBFT-based, hybrid, and Directed Acyclic Graph (DAG) architectures enable low-energy and low-cost event logging. This study bridges the gap between established DLT sustainability research and the operational requirements of regulated forestry traceability by providing a transparent and reproducible benchmarking workflow that includes URLs, access dates and calculation spreadsheets.