Clustering is an effective approach for organizing the network into a connected hierarchy, load balancing, and prolonging network lifetime. Clustering protocols in wireless sensor networks are classified into static and dynamic. In static clustering, clusters are formed once, forever and role of the cluster head is scheduled among the nodes in a cluster. However, in dynamic clustering the time is divided into rounds and clustering is performed in the beginning of each round. This paper presents a Hybrid Clustering Approach (HCA). Whenever a cluster head consumes a prespecified part of its energy, it indirectly informs all other nodes so, clustering will be done in the beginning of the upcoming round. Therefore, clustering is performed on demand. To evaluate the efficiency of proposal, the well known distributed clustering protocol, HEED, is used as baseline example. By means of simulation results, we demonstrate that significant energy saving can be achieved using HCA

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