LED street light

Last updated
LED street light
Led streetlight.jpg
LED street light in the United Kingdom
Component type LED, street light

An LED street light or road light is an integrated light-emitting diode (LED) light fixture that is used for street lighting.

Contents

Design and style

LED street light beam pattern Led street light beam pattern.jpg
LED street light beam pattern

An LED street light is an integrated light that uses light emitting diodes (LED) as its light source. These are considered integrated lights because, in most cases, the luminaire and the fixture are not separate parts. In manufacturing, the LED light cluster is sealed on a panel and then assembled to the LED panel with a heat sink to become an integrated lighting fixture.

Different designs have been created that incorporate various types of LEDs into a light fixture. Either few high-power LEDs or many low-power LEDs may be used. The shape of the LED street light depends on several factors, including LED configuration, the heat sink used with the LEDs and aesthetic design preference.

Heat sinks for LED street lights are similar in design to heat sinks used to cool other electronics such as computers and smart street light energy saving systems. Heat sinks tend to have as many grooves as possible to facilitate the flow of hot air away from the LEDs. The area of heat exchange directly affects the lifespan of the LED street light.

The lifespan of an LED street light is determined by its light output compared to its original design specification. Once its brightness decreases by 30 percent, white (clear) an LED street light is considered to be at the end of its life.

Most LED street lights have a lens on the LED panel, which is designed to cast its light in a rectangular pattern, an advantage compared to traditional street lights, which typically have a reflector on the back side of a high-pressure sodium lamp. In this case, much of the luminance of the light is lost and produces light pollution in the air and surrounding environment.

A drawback of LED focus panels is that most light is directed to the road, and less light to the footpaths and other areas. This can be addressed by the use of specialized lens design and adjustable mounting spigots.

In performing a LED street lighting project, easy LED luminary models simplify the optimization for high-performance illumination designs. [1] These practical equations may be used to optimize LED street lighting installations in order to minimize light pollution, increase comfort and visibility, and maximize both illumination uniformity and light utilization efficiency.

Energy efficiency

The life span of an LED as compared to other light sources LED Street Light Life Span-1.jpg
The life span of an LED as compared to other light sources

The primary appeal of LED street lighting is energy efficiency compared to conventional street lighting fixture technologies such as high pressure sodium (HPS) and metal halide (MH). Research continues to improve the efficiency of newer models of LED street lights (modernizing with LED street lights). However, LED street lighting is not as efficient as low-pressure sodium (SOX) street lighting in the United Kingdom. [ clarification needed ]

An LED street light based on a 901-milliwatt output LED can normally produce the same amount of (or higher) luminance as a traditional light, but requires only half of the power consumption. LED lighting does not typically fail, but instead decreases in output until it needs to be replaced. [2] It is estimated that installation of energy efficient street lighting in the 10 largest metropolitan areas in the U.S. could reduce annual carbon dioxide emissions by 1.2 million metric tons, the equivalent of taking 212,000 vehicles off the road, and save at least $90 million annually in electricity costs. [3] [4]

As LED lighting fixtures normally produce less illumination [5] it is important to use a well-distributed illumination pattern in order to produce the same illumination as higher-lumen conventional fixtures. For example, different LEDs in one fixture can target different points on the street.

Advantages of LED street lights

Disadvantages of LED street lights

Malfunctioning LED street lights flickering
Defective LED street light turned purple Defective LED street light turned purple.jpg
Defective LED street light turned purple

Health concerns

References

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