As our nation’s high-speed road construction extended from east plain region to the west mountainous area, tunnel is widely used during the construction. To employ new technology and new products to lower the energy conservation in tunnel lighting has become the trend as the large energy consumption of traditional tunnel lighting. Therefore, Ministry of Transport promoted LED lighting system on expressways in Yunnan, Hebei, Guanggxi provinces to realize intelligent sensor system which greatly save the energy.
In front of Maodaozi tunnel on Yunnan Dabao expressway, a car is driving into the tunnel. The vehicle detector sensitively detected this car and PLC control system activates lighting circuit promptly in the tunnel and the LED energy-saving light is on when the car is 200 meters away from the portal. The car drives into and out of the tunnel smoothly. After detecting the leave of the car in another portal, the control system shut down the lighting to avoid unnecessary energy waste when there is no car in the tunnel. According to the introduction of experts, the high energy-saving effect of LED tunnel lighting, on one hand benefits from the characteristics of high luminous efficiency and low power consumption itself; on the other hand, the adjustable luminance of LED can adjust the light in the tunnel to meet the need of the drivers thus initiating the lighting control technology to save the energy remarkably.
Maodaozi tunnel in Yunnan implements 3 energy-saving renovations of LED lighting technology, distribution system active power filter technology and nighttime vehicle induction lighting system. The project substitutes 770 sets, 146.19 kilowatt high pressure sodium lamp equipment with 858 sets, 51.64 kilowatt LED lighting to cut down electricity consumption; Active power filter device reduces electric equipment damage due to the unstable electricity supply; To initiate vehicle induction lighting control system at night not only ensures the lighting demand for but reduces invalid lighting when no vehicles passing by. Compared to high pressure sodium lamp, the comprehensive electricity saving rate can reach to 66%.