To safeguard sensitive data within smart grid infrastructures, utility companies and grid operators should implement robust encryption measures prior to data transmission and storage. While encryption ensures confidentiality, it introduces challenges related to data sharing among various stakeholders in the smart grid ecosystem. Re-encrypting using a proxy server offers a viable solution by allowing data owners to delegate decryption rights to authorized recipients (such as third-party service providers, regulators, or consumers) without direct interaction. In this work, we propose a pairing-free proxy re-encryption (PF-PRE) scheme, specifically designed for smart grid applications which uses certificate authorities. It offers a safer and faster solution to data confidentiality in smart grid communications and storage systems. The security of the proposed scheme is validated in random oracle model using computational Diffie-Hellman assumption. By eliminating computationally intensive bilinear pairing operations, the scheme achieves a substantial reduction in computational overhead, which is crucial for the resource-constrained devices often found in smart grid environments. This approach enhances data protection and sharing capabilities across the complex network of smart meters, substations, control centers, and other grid components, while maintaining efficiency and scalability.