International Journal of Research in Advanced Electronics Engineering
2026, Vol. 7, Issue 1, Part A
Design of automatic street light dimming system using LoRa communication for energy conservation
Author(s): Carlos Eduardo Santos and Ana Paula Oliveira
Abstract: Street lighting represents a substantial component of municipal energy consumption, with conventional fixed-schedule operation maintaining full illumination throughout nighttime hours regardless of actual pedestrian or vehicular activity. Adaptive dimming strategies responding to real-time occupancy and ambient light conditions offer significant energy savings potential, yet require reliable communication infrastructure connecting distributed light nodes to central management systems. This research presents the design and validation of an automatic street light dimming system utilizing Long Range (LoRa) wireless communication technology, enabling centralized control of distributed lighting nodes across urban residential areas while achieving energy savings exceeding 40% compared to conventional operation. The system architecture comprises smart lamp nodes integrating ATmega328P microcontrollers with SX1276 LoRa transceivers, passive infrared motion sensors, and light-dependent resistor ambient light detection. Each node controls a 100W LED luminaire through pulse-width modulation dimming, receiving scheduling commands from a LoRa gateway while reporting status and sensor data for central logging and analysis. The gateway employs a Raspberry Pi 4 with RAK2245 LoRa concentrator module providing multi-channel reception supporting up to 100 end nodes within 5 kilometer urban range. A 30-day pilot deployment across 50 street lights in a suburban residential district of São Paulo validated system performance under real operating conditions from September to October 2024. The adaptive dimming algorithm reduced average power consumption from 100W baseline to 58W through scheduled dimming during low-activity periods with motion-triggered full brightness restoration. Communication reliability exceeded 99.2% packet delivery rate across the deployment area, with node-to-gateway latency averaging 340 milliseconds enabling responsive occupancy-based dimming adjustments. Energy consumption analysis demonstrated 41.3% reduction compared to conventional fixed-schedule operation, translating to monthly savings of 742 kWh for the 50-lamp pilot system. Projected annual cost savings of R$ 7,123 at current electricity tariffs yield system payback within 25 months including hardware and installation costs. The environmental benefit corresponds to approximately 713 kg annual CO₂ emission reduction based on Brazil's electricity generation mix. The research demonstrates that LoRa communication provides cost-effective infrastructure for smart street lighting networks, with long-range capability reducing gateway density requirements while license-free spectrum operation eliminates recurring communication costs. The validated 41% energy savings potential positions adaptive LoRa-based dimming as a practical pathway for municipalities seeking lighting efficiency improvements within constrained infrastructure budgets.
DOI: 10.22271/27084558.2026.v7.i1a.76
Pages: 45-51 | Views: 39 | Downloads: 19
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How to cite this article:
Carlos Eduardo Santos, Ana Paula Oliveira. Design of automatic street light dimming system using LoRa communication for energy conservation. Int J Res Adv Electron Eng 2026;7(1):45-51. DOI: 10.22271/27084558.2026.v7.i1a.76
