Wireless Sensor Network (WSN) consists of number of sensor nodes clustered together to collect various environmental or other physiological data like temperature, pressure, seismic graph, sound, location, etc. WSNs are used in various fields like healthcare, monitoring systems, military, etc. Sensor nodes run on battery without direct power supply. Hence, energy efficiency becomes the major issue in WSNs to make WSNs run for longer. Because these wireless sensor nodes run on batteries and they carry a limited battery life. Routing process and sensing process consumes the battery power. Sensing process is the primary process of sensor nodes, hence, cannot make changes in this process.