A LoRa Based IoT Framework for Real-Time Lux Monitoring and Energy Efficient Lighting Management

Ranjana Ubale, Kailash Sapnar

Abstract: Recent advances in Internet of Things (IoT) technologies, low-power wireless communication, and embedded electronics have created practical opportunities for continuous illumination monitoring in energy conscious buildings. This study presents a LoRa based IoT framework for distributed, real time lux sensing and energy efficient lighting management. The framework combines BH1750 digital light sensors, an ESP8266 microcontroller, SX1278 LoRa transceivers, and a gateway connected monitoring interface to acquire and transmit indoor illuminance data. The experimental evaluation was conducted in an office room with an area of approximately 9.01 m? using two Philips LED luminaires with a DIALux input power of 36W per luminaire and a target illuminance of 200 lux. The DIALux model was compared with hardware measurements under artificial light only and daylight assisted conditions. The BH1750 sensing unit was validated against a standard lux meter, with an average measurement error of approximately 3.18%. During the office test, illuminance was monitored from 10:00AM to 5:00PM, and observation points were used for simulation to measurement comparison. The temporal profiles showed a strong positive correlation between simulated and measured illuminance. The LoRa link operated at 433MHz with a 10-second application layer transmission interval, and no packet loss was observed during the logged test run. The results demonstrate that real time lux monitoring can reveal daylight availability and provide a practical data layer for daylight responsive lighting management. The study focuses on the demonstrated monitoring capability; automatic closed loop dimming and relay control are identified as future extensions.

Keywords: Internet of Things, LoRa, Lux Sensing, Illuminance Monitoring, Smart Lighting, Energy Efficiency