Design and implementation of an energy management system based on distributed IoT

•A Distributed IoT-based Energy Management System was implemented and tested at two institutions far apart.•The system utilizes ESP32 microcontrollers and features two main phases for monitoring and controlling power usage indicators.•Three primary approaches were taken for monitoring different areas of the institutions.•A large database of energy consumption data was collected, with over two million data rows already collected and an anticipated ten million by the end of 2023.•The system was able to reduce energy consumption in the Duhok-controlled laboratory by significant ratios.•The study highlights the challenges of reducing energy use and the potential benefits of a distributed energy management system with IoT sensors.