LED Street Lights VS Conventional:Which Lamp Is Best For Road Lighting?

LED street light takes light emitting diode as light source, because it is a kind of solid cold light source, it has the characteristics of environmental protection, no pollution, less power consumption, high light efficiency and long life.LED street lamps are gradually coming into people's sight due to these advantages of directional luminescence, low power consumption, good driving characteristics, fast response, high seismic capacity, long service life, green environmental protection etc.It has become a new generation of energy saving light source which has the advantage of replacing traditional light source.Therefore, LED street light is the best choice for energy saving transformation of road lighting.

I The features of LED street light

Compared with conventional high pressure sodium street lamp,the light source of high-power LED lamp adopts low-voltage DC power supply, high-efficiency white diode synthesized by gan-based power blue LED and yellow phosphor powder,which has the unique advantages of high efficiency, safety, energy saving, environmental protection, long life, fast response speed, high color rendering index,can be widely used in urban road lighting.The housing can be made of PC pipe, with high temperature resistance up to 135 degrees and low temperature resistance up to -45 degrees.

The light-emitting diode (led) is based on the weak power of the semiconductor pn junction to light the efficient solid-state light source, and in the positive partial voltage and injection current, the injection of the hole in the p area and the electrons injected into the n zone are emitted by the radiation of the active zone and the photons are generated by the radiation, and the electricity is converted directly into light energy.

II Advantages of LED street light

1. Intrinsic characteristics of LED lamps:unidirectional, no light diffuse, to ensure the efficiency of lighting.

2. The LED street lamp has a unique secondary optical design, which irradiates the light from the LED lamp to the desired public lighting area, further improving the lighting efficiency to achieve the purpose of energy saving.

3. The light source efficiency of LED street light has reached 110-130lm/W, and there is still a lot of room for development, theoretically can reach 250lm/W.While the luminous efficiency of conventional high-pressure sodium lamp increases with the increase of power, so the overall luminous efficiency of LED lamp is stronger than that of conventional.

4. The color rendering of LED road light is much higher than that of conventional lamp. The color rendering index of high-pressure sodium lamp is only about 23, while the color rendering index of LED lamp reaches more than 75.From the perspective of visual psychology, to achieve the same brightness, the average illumination of LED street light can be reduced by more than 20% than the conventional lamp.(Refer to British lighting standard)

5. LED street lamps have low light decline, less than 3% in a year, and still meet the illumination requirements for road lighting after 10 years of use.While the light failure of conventional lamp is high,decline over 30% after one year.Therefore, the power of LED street lamps can be designed to be lower than that of high-pressure sodium lamps.

6. LED street lights have automatic control energy-saving devices, which can reduce power as much as possible to meet the requirements of different periods of lighting and save electric energy.Intelligent LED street light researched & produced by EXC Streetlight can achieve computer dimming, time control, light control, temperature control, remote control, automatic inspection and other humanized functions.

7. LED is a low-voltage device, driving a single LED voltage for safety voltage, the power of a single LED series of products are 1 watt, so it is a safer power than the use of conventional high-voltage power supply, especially suitable for public places(such as:road lighting,factory lighting, automotive lighting, civil lighting etc).

8. Due to the small size of each LED chip, devices of various shapes can be fabricated and adapted to changeable environments.

9. Long service life: can be used for more than 50,000 hours, providing three years of quality guarantee. The disadvantage is that the life of the power supply is not guaranteed.

10. High light efficiency: Using the chip of ≥100LM, can save more than 75% energy compared with the traditional high pressure sodium lamp.

11. Easy installation: the lamp cap is directly installed on the lamp pole or the light source is nested in the original lamp shell without embedding cables and rectifier.

12. Reliable quality: high quality components are used for the circuit power supply, and each LED has a separate overcurrent protection, so there is no need to worry about damage.

13. Uniform light color: no lens, no sacrifice of uniform light color to improve brightness, so as to ensure uniformity of light color.

14. Led does not contain the harmful metal mercury,unlike high-pressure sodium or metal halide lamps, which can be hazardous to the environment when scrapped.

Based on the above principles, the energy-saving effect of high-power LED street lamp is remarkable, and it can save more than 60% electricity instead of high-voltage sodium lamp.Low maintenance cost: Compared with traditional street lamps, THE maintenance cost of LED street lights is very low. After comparison, the investment cost can be recovered in less than 6 years.

III Disadvantages of LED street light

1. Low power of a single LED.In order to obtain high power, multiple parallel connections are required.

2. Low color rendering index. The color displayed under LED irradiation is not as true as incandescent lamp, which is a technical problem based on the analysis of spectral distribution.

3. Light spot. The "yellow circle" problem is easy to be caused by the defect of white LED manufacturing process and the matching error between white LED and reflection cup or lens.

4. LED irradiation uniformity problem.If the secondary optical design is not carried out, the irradiation of LED lighting products is relatively concentrated, so it is necessary to carry out the secondary optical design, so that the light intensity distribution map is bat-shaped.

5. LED light decay problem.Compared with low-power LED, the light decay problem is not so bad of high-power LED street lamps.

In order to improve energy efficiency, protect the environment, to cope with global climate change, as the most advantageous new high-efficiency energy-saving lighting products, LED lighting products are the key promotion products of energy-saving lighting fixtures worldwide.Previously, due to the higher price of LED lighting products compared to traditional lighting products, its market penetration has been at a low level.

As countries around the world increasingly pay attention to energy conservation and emission reduction, the improvement of LED lighting technology and the decline of the price, as well as countries have issued a ban on the production and sale of incandescent lamps, the promotion of LED lighting products under the background of favorable policies, LED lighting product penetration is increasing.The global LED lighting penetration rate reached 36.7% in 2017, up 5.4% from 2016, and rose to 42.5% in 2018.

IV Development prospect of LED street lamp

Although LED is affected by the efficiency of lighting and light source, it is also favored by customers for its high luminance, long service life and outstanding energy saving.The lighting performance of outdoor led road lighting lamps is developing towards the comfort, will not blindly pursuit too much in the term of high lighting efficiency, can find a balance point between the light efficiency and price.

In the future, additional functions such as light control, time control and Internet of things will be added to the commercial LED street lamps, which can not only improve the added value of lamps, but also meet the development needs of smart cities in the future.

In short, whether LED can be applied in a wider range of practice, so as to unify the overall situation of street lighting application, the determinants include safety and reliability, economic practicality, lighting effect and other multiple factors.And with the development of 5G, LED street lamps will usher in a major "reform", to ensure stable product quality, affordable, strong use effect, will win more trust and use.Only by strengthening technological research and development and continuous innovation,can ensure the development of LED lamps in a scientific, green, efficient and sustainable direction.