AMI-Chain: A scalable power-metering blockchain with IPFS storage for smart cities

There is a growing interest in utilizing blockchain technology to safeguard grid assets, promote environmental sustainability, and enhance services in smart-city power grids. However, scaling a blockchain to accommodate the multitude of energy sources, prosumers, and consumers is an ongoing challenge. To address this issue, we propose AMI-Chain, a cost-effective blockchain solution that leverages the Inter-Planetary File System (IPFS) for off-chain storage, data aggregation, and compression at the smart meter level. This approach significantly boosts blockchain transaction rates and scalability. However, employing IPFS introduces its unique challenges, particularly in having nodes that stop participating at any given time. Therefore, we also present effective strategies for managing a large number of consumers and introduce a model for optimizing IPFS storage while ensuring data durability. Estimations with our model reveal that AMI-Chain can support over 7.7 million smart meters with a 24-h data compression rate while providing eleven nines for one-year data durability.