WSNs are becoming popular in real world uses. Due to resource-constrained and battery-aware features of the sensor; WSNs energy use in a major research topic was found to be interesting. WSNs contain battery powered nodes that for certain action or tasks are connected with the base station. The lifetime of battery-powered sensor nodes, after the consumption of the battery will be dead in WSNs. To prolong the lifetime of WSNs the energy has to be well organized. The cluster head selection and assignment, and construction of clusters require additional overhead. Cluster nodes distributed algorithms designed incorrectly can lead to isolation from cluster heads. Such isolated nodes waste large amount of energy to communicate with the sink. In this paper, energy conservation techniques related to WSNs are discussed. Also, the existing energy conservation algorithms are reviewed and the comparative analysis is also performed.