Self-Optimizing the Environmental Sustainability of Blockchain-Based Systems

Blockchain technology has been widely adopted in many areas to provide more dependable and trustworthy systems, including digital infrastructure. However, this technology is acknowledged to pose severe threats to the environment; its wide adoption is believed to be among the significant modern technology contributors to greenhouse gas emissions. The fundamentals of the technology and the inefficiencies of its underlying consensus algorithms (e.g., Proof of Work) are cited among the reasons for these shortcomings. In particular, trust guarantees through consensus are expensive and require excessive computational power, leading to considerable carbon emissions. In this paper, we propose a novel self-adaptive model to optimize the environmental sustainability of blockchain-based systems. It balances the systems' energy consumption and carbon emission without compromising the fundamental properties of blockchain technology. The model continuously monitors a blockchain-based system and adaptively selects miners, considering context changes and user needs. The model dynamically selects a subset of miners to perform sustainable mining processes while ensuring the decentralization and trustworthiness of the system. The aim is to minimize blockchain-based systems' energy consumption and carbon emissions while maximizing their decentralization and trustworthiness. We conduct experiments to evaluate the efficiency and effectiveness of the model. The results show that our model for self-optimizing the environmental sustainability of blockchain-based systems can reduce energy consumption by 55.49% and carbon emissions by 71.25% on average while maintaining desirable levels of decentralization and trustworthiness by more than 96.08% and 75.12%, respectively. Furthermore, these enhancements can be achieved under different operating conditions compared to similar models, including the straightforward use of Proof of Work. Also, we have investigated and discussed the correlation between these objectives and how they are related to the number of miners within the blockchain-based systems.