<p>The development of smart grids requires smart meter reading and metering networks to support large-scale, low-power, and real-time data collection on the user side. In these networks, many energy-constrained sensor nodes are densely deployed to monitor multi-dimensional power parameters, making energy-efficient routing a critical challenge. Among various routing protocols for wireless sensor networks (WSNs), the LEACH protocol is still widely used as a foundational clustering scheme for intelligent meter reading networks because of its distributed clustering, low-complexity deployment, and good scalability to large-scale WSNs. However, traditional LEACH ignores node residual energy, node-to-base-station distance, and local node density in cluster-head (CH) election, which leads to unbalanced energy consumption and a shortened network lifetime. To address these limitations, this paper proposes an enhanced low-power clustering routing protocol, EIMP-LEACH, tailored for intelligent meter reading and metering networks. First, an improved CH election threshold is designed by jointly incorporating three factors: node residual energy, distance to the base station, and local node density. This design achieves a more balanced spatial distribution of CHs and reduces excessive energy depletion at individual nodes. Second, a bidirectional clustering mechanism for ordinary nodes is introduced, where the association between ordinary nodes and candidate CHs is determined by a clustering priority function that considers CH residual energy, communication distance, and communication radius, thus further balancing the network load. Finally, the performances of EIMP-LEACH, IMP-LEACH, TS-I-LEACH, and the traditional LEACH protocol are compared through MATLAB-based simulation experiments. The results show that EIMP-LEACH effectively prolongs the network lifetime and reduces the total energy consumption of the system compared with all baseline protocols.</p>