One of the most effective ways to reduce energy usage in a smart city is to use the Internet of Things (IoT). This and other technologies working based on innovative ways can be used to control energy transition remotely, turn on street lights automatically and manage temperature and pressure in smart buildings. These smart technologies are also capable of predicting peak usage times and reducing CO2 emissions associated with meter readings. With IoT, building managers can optimize energy consumption and automate operations, resulting in significant energy saving.