Internet of Things (IoT) is a system that renders the ability to exchange information and actions in an amalgamated environment consisting of machines and humans over a network. Such extraction of information flow through network will optimize the limitations of the physical world. A key player in the realization of IoT system is power management. In this paper, need for power management in an application based IoT design is motivated. The paper outlines the factors concerning power management in IoT design for example, aging in battery sources, sleep and shutdown mode of operation, etc. Furthermore, the paper reviews some of the techniques like power grating, maximum power point tracking, etc. for currently used power sources that aid to enhance the performance of the system. The technical challenges faced in the IoT field for circuit power up and battery lives have also been discussed. Since power is imperative in variegated engineering disciplines all around the field of science and also is a fundamental prerequisite for the IoT system design. Wireless sensors, servers, Ethernet, and smart appliances, as a part of an IoT based solution are all affected by the scope of power management. With the novel IoT solutions operating under the absence of human intervention at data collection stage, it is crucial for the devices to be powered up smartly to offer accurate results and good performance.