Wireless sensor network (WSN) consists of a large number of sensor nodes which are able to sense their environment and communicate with each other using wireless interface. However these sensor nodes are constrained in energy capacity. The lifetimes of sensor node and sensor network mainly depends upon these energy resources. To increase the life time of sensor network, many approaches have been proposed to optimize the energy usage. All these proposed protocols mainly use minimum hop or minimum energy path. Continuously using the shortest path will deplete energy of the nodes at a much faster rate and causes network partition. This paper proposes an energy efficient routing protocol to extend the network lifetime for delay constrained network. Each sensor node selects the optimized path for forwarding packets to the base station based on routing metrics. Proposed studies and simulation results shows that the protocol put forward in the paper can achieve higher network lifetime by striking a balance between the delay and power consumption in comparison to other routing protocols.