Density Based Solar Powered Traffic Control System

The rapid increase in urban vehicle numbers has made traditional fixed-time traffic signal systems ineffective, leading to congestion and unnecessary fuel consumption. Conventional signals follow preset timing cycles and cannot react to real-time traffic conditions, which causes vehicles to wait even when some lanes are empty. To overcome this problem, this paper proposes a Density-Based Solar Powered Traffic Control System using an ESP32 microcontroller. The system uses two Infrared (IR) sensors in each lane to estimate traffic density and classify it into low, medium, and high levels based on vehicle position. According to the detected density, the signal timing is adjusted dynamically, giving longer green signals to congested lanes while skipping empty ones to improve traffic flow and reduce waiting time. An RFID-based priority feature is included to detect authorized emergency vehicles such as ambulances and fire brigades, and the controller immediately overrides the normal sequence to clear the intersection. For better user awareness, an OLED display provides a visible countdown timer for signal changes, and a buzzer gives an audible alert during emergency operation. The system is powered by a solar panel as the main energy source along with a rechargeable battery backup, and during low sunlight the battery can be charged from the electrical grid to maintain continuous operation. Overall, the proposed system offers a simple, reliable, and energy-efficient approach suitable for smart city traffic management.