Comparison of LED and traditional lighting
At present, traditional high-pressure gas discharge light sources (HID), such as high-pressure sodium lamps (HPS) and metal halide lamps (MH), are still the main force of tunnel lighting. The tunnel lighting scheme requires a high minimum illuminance to provide a safe environment for users. The luminaire must be able to provide a high level of light at a considerable distance from the plane. The typical installation height of road tunnels is 5-7 meters, providing clearance for high-side vehicles.

High-pressure sodium lamps and metal halide lamps are very attractive to tunnel lighting scheme designers, providing both low unit cost and high illuminance. Arrays of high-pressure sodium lamps and metal halide lamps usually have a power of up to 400W per lamp to meet the illumination requirements.

However, the disadvantages of high-pressure sodium lamps (HPS) (Figure 1) and metal halide lamps (MH) are obvious. These two types of lamps consume a lot of energy, usually have low light quality, and cannot provide uniform lighting in the tunnel, and if a failure occurs, expensive maintenance programs are required to remedy. Now, with the advancement of LED technology, tunnel operators have a new choice, which is more and more attractive from the public and operational perspectives.
The most obvious advantage of LED-based tunnel lights is their long life and high efficiency:

In typical tunnel lighting applications, high-quality LED lighting systems can provide >100 lumens/watt. Since the LED is a directional point light source, its light output can be accurately transmitted to the required area, providing additional system efficiency compared with the HID system.

LED is a very reliable semiconductor device with a very long service life, which greatly reduces maintenance and service costs.

Ningbo Tianyi Electric Appliance Co., Ltd. is situated in Zhouxiang town Cixi city, one of China’s pilot towns in the UN sustainable development program. We have a very attractive geographical advantage with No. 329 National Highway and Hu-Hang-Yong Highway (which connects Shanghai, Hangzhou and Ningbo) to the south, Hangzhou Bay Bridge to the north and Ningbo Beilun port and Ningbo International airport to the east.