With the incorporation of the Internet of Things (IoT) in the power sector, the modern landscape of energy consumption is undergoing a transformational shift. The insights gained through the data generated through an IoT help to address various problems associated with it by providing data analytics solutions. Based on this, real-time monitoring, energy forecasting, and demand response can be done effectively. This study review digs into the diverse areas of IoT applications in energy management, attempting to grasp the complexities, problems, and opportunities this synergy presents. It covers a wide range of energy sectors, including smart grids, industrial processes, and residential settings, where IoT technologies play a critical role in optimizing energy usage. This paper reviews a broad perspective of IoT in energy management and opportunities in various segments. This paper highlights the challenges in applying IoT and the practical solutions to the challenges.