I believe that most people have the experience when they are flying: on a clear night, looking out the window of the passenger plane, most of the cities below the plane are bathed in bright orange light. This is mainly because the light is emitted by thousands of high-pressure sodium lamps. Lighting expert Ron Bednarick said: "From the sky, most cities look like orange spots."
However, with the road lighting revolution, LEDs have gradually replaced high-pressure sodium lamps with the advantages of longer service life and better light generation, and this is beginning to change.
It is estimated that the total number of street lamps in the United States is between 45 million and 55 million. Among them, most street lamps are high-pressure sodium lamps, and a small portion are metal halide lamps.
Lighting expert Ron Bednarick said: "The adoption speed of LEDs may have tripled in the past two years." "Because of the use of LED lamps, the quality of light is significantly improved, and the cost savings are also significant."
He believes that LED street lights have three major advantages: First, the light of the well-designed LED street lights is clear, controllable and beautiful. The precisely designed optics in the LED luminaire ensure that the light illuminates where it belongs, which means less wasted light. Second, LED lamps have lower maintenance costs and lower energy consumption. Since most road lights are owned and operated by utility companies, the use of LEDs can reduce energy consumption by approximately 40%. At the same time, the more important savings are maintenance. Since the lumen output of the high pressure sodium lamp is reduced, the high pressure sodium lamp must be replaced at least every five years. Material and labor for a single bulb replacement can cost between $80 and $200. Since the life of LED luminaires is three to four times longer than HID, the cost of a single maintenance can be very large. Third, decorative LED street lighting is growing. With the improvement of technology and the reduction of manufacturing costs, lighting manufacturers can provide a wider range of decorative lighting options, can imitate the lighting design of old gas lamps, and so on, which is very aesthetically pleasing.
A few years ago, LED luminaires only accounted for a small portion of the road lighting market. The high cost of LEDs makes it difficult for most towns to convert compared to HID lamps. But today, with the advancement of LED lighting technology and the decline in prices, the pace of LED adoption is accelerating. In the future, road lighting will be LED.