Energy conservation plays a role important in wireless sensor network (WSN) design. The technique of clustering is one of the approaches to save energy of WSNs; several protocols based on the clustering technique are proposed in the context of energy conservation and maximization of network lifetime. This article proposed a new routing technique to maximize the network lifetime and enhance energy efficiency in WSNs, namely optimal selection of cluster head in the grid (OSCH-Gi). This technique divides the network area into a clustered grid. Each clustered grid has a cluster head (CH) it has been chosen based on the residual energy and distance to the base station of each node. Simulation results indicate that the proposed technique is more effective than other clustering algorithms in terms of the network lifetime and energy consumption.