Abstract: With the digital transformation of the power industry and the widespread adoption of smart grid technologies, the massive volume of data generated within power systems has imposed higher demands on secure storage and efficient access. However, traditional data storage models face challenges, such as difficulties in regulatory supervision and low efficiency in data traceability. To address these issues, this paper proposes a secure storage and access control scheme for power data based on consortium blockchains. In this scheme, a hybrid storage model combining on-chain and off-chain mechanisms is established, the encrypted power data is stored in the storage server, and the key information is recorded on the consortium blockchain, which ensures data confidentiality, immutability, and traceability. An encrypted data storage method supporting keyword search is designed by Bloom filters and symmetric encryption. While ensuring the secure storage of data, the designed method achieves efficient data retrieval and enhances the practicality of systems. Moreover, smart contract and blind signature are utilized to achieve user attribute-based access control, which achieves fine-grained permission management and ensures the security and flexibility of data access. A formal security analysis demonstrates that the proposed scheme can effectively resist impersonation and eavesdropping attacks while ensuring the security of keyword information. Performance evaluation shows that, compared with existing schemes, the proposed solution reduces computational overhead by 68% during the data search phase and lowers communication overhead by 37% during the data access phase.