What are the disadvantages of LED street lights compared to traditional high-pressure sodium lights

In response to the national call for energy conservation and emission reduction, more and more roads have replaced the original street lamps (high pressure sodium lamps) with LED street lamps, changing from yellow light to white light, and street lamps with higher illuminance seem to illuminate the road. It's brighter and it seems safer to drive at night. Is that really the case?

It is a general trend that LED street lamps replace traditional high-pressure sodium lamps. However, as far as the current actual experience is concerned, LED street lamps are not a complete victory. In many respects, LED street lamps have more disadvantages.

One, glare
The glare sense of LED street lights with higher installation height is not very strong. However, if you install low-level LED street lights, close to the illumination range of these street lights, you will have an obvious dazzling sensation, and if you go out of the illumination range, your eyes will feel black again. However, there is no such clear feeling within the lighting range of the high pressure sodium lamp.

Two, color rendering index
LED lights have higher illuminance, can illuminate the road brighter, but where the low color temperature light source illuminates, the naked eye feels that all objects are white, and the difference between the object and the road becomes more small. Under LED street lights, we cannot accurately distinguish the stones on the road from the road surface.
In addition, because the LED street lamp does not have a reflector bowl and there are many luminous bodies, the actual light emitted is relatively scattered, giving people a bright and not concentrated feeling. The high-pressure sodium lamp is the opposite, because the light is more concentrated due to the reflection of the lamp bowl.

3. Penetration ability in rainy and foggy weather
Although there are a lot of data on the Internet to prove that the penetration of LED street lamps is better than that of high-pressure sodium lamps, the actual situation is that in rainy and foggy weather, especially foggy weather, we can see more clearly under high-pressure sodium lamps. Although LED street lights have an advantage in brightness, I can only feel the whiteness in the fog. The brightness is enough, but nothing can be distinguished.

Fourth, the stability of the light source
Domestic LED street lights will have high-frequency flicker. If standing under a street light, the human body will obviously feel faint, which will seriously affect the vision of drivers and passers-by, posing a traffic safety hazard. In addition, many LED street lights on the road have a certain decline in illuminance as the use time increases, that is to say, the more they are used, the darker they are.

Five, LED street lights are expensive
The price of LED street lights is ~ times that of traditional street lights, and the cost is high.

Everything is good or bad, there is no absolute good or bad. LED lights are still in a process of continuous evolution. With the continuous advancement of energy saving and emission reduction, it is only a matter of time before LED street lights fully replace high-pressure sodium lights.