Development of SMART Schedule Room for Safe Energy System : Intelligent Energy Management Using MySQL Database and Network-Based Microcontroller Control

Abstract

This research aims to develop a smart room management system called "SMART Schedule Room for Safe Energy" to reduce electrical energy consumption and enhance classroom control efficiency at the Faculty of Engineering, Khon Kaen University. The system employs an integrated process combining schedule-based control for advance room booking, automatic control of electrical appliances, and artificial intelligence processing on a Central Edge Server. For the energy reduction process, a C++ Background Service operates on the server to monitor the room booking database and send on/off commands for electrical appliances to an STM32 microcontroller, while receiving room temperature data via RS485 communication according to the booking schedule. This is combined with an IP Camera utilizing the YOLOv8 model to detect movement and other abnormal conditions in real-time through the RTSP Video Stream protocol. If no user presence is continuously detected beyond a specified time threshold, the system updates the status in the MySQL database and immediately cuts off the power supply, while sending alert notifications for abnormal conditions via the LINE Messaging API and email. The results of a 6-month field trial showed that the system could reduce average electrical energy consumption from 423.3 kWh to 277.3 kWh per month, saving an average of 146 kWh per month, or 34.49%, which was a statistically significant reduction at the 0.05 level (t = 56.52, p < 0.001). Economic analysis indicated that with an installation cost of 4,000 THB per room, the payback period was 6.85 months, the net present value (NPV) was 17,215.11 THB, and the return on investment (ROI) reached as high as 430.38% over a 5-year service life. These findings demonstrate high efficiency and cost-effectiveness for scaling up implementation at the organizational level.