Wireless sensor networks are becoming an integral part of numerous applications very quickly. Here, we present a new approach for sensor applications that requires coverage for a large area, stationary environment, and simplicity in the sensor nodes. Our protocol combines features such as data aggregation, energy aware routing, clustering and hierarchical routing into a single protocol. All these features combined allow for increased energy efficiency as well as extended network lifetime. Dynamic clustering is utilized to allow the sensors to change their cluster association dynamically. Data aggregation is incorporated to allow different data packets to be combined together in order to conserve energy and finally hierarchical routing is used to bridge large distances. We provide all the protocol specifications and our simulation results obtained with NS-2. Our simulations show that we could extend the network lifetime by a factor of two by using the proposed protocol HEAR-SN.