A blockchain-based framework for carbon management towards construction material and product certification

As one of the biggest resource consumers and carbon emitters, the construction industry plays a crucial role in global carbon reduction. Carbon certification or labelling schemes are efficient ways to assess and report the carbon footprints of construction materials and products (CMPs), providing the foundation for carbon management at the CMP level. However, existing carbon management for CMP certification relies heavily on traditional centralized data management tools, which suffer from data non-transparency and manipulation problems, making carbon footprints unreliable and hard to track. Therefore, benefiting from the immutability and traceability of blockchain, this paper introduces a distributed solution for transparent and secure carbon management towards CMP certification. Contributions lie in three aspects: (1) a Green Product Chain (GPChain) framework is proposed based on blockchain. This framework provides a distributed and transparent carbon data-sharing environment, enabling reliability and traceability during certification. (2) A blockchain data model is developed considering the privacy of carbon data for CMP certification. Besides, a privacy-preserving carbon data-sharing strategy is designed for pre-processing different sensitive data before being transferred to the blockchain. (3) GPChain smart contracts are developed to granularly control user interactions with blockchain and automatically generate distributed carbon footprint records. Results show that (1) GPChain's feasibility of supporting carbon management for GMP certification and (2) the acceptable performance of GPChain smart contracts during operations.