LED technology has a lot of advantages. But in practical, applications of LED lighting sources still have many restrictions, which have been the largest obstacles in the path of LED highway applications.
1) Heat dissipation.
Improving the heat problem of LED lights is always one of the biggest challenges for LED manufactures. The working condition and heat dissipation is the two major factors that can determine the real light efficiency of LED lamps and certainly the service life of them. Generally, when we discussed about the light efficiency of LED lamps, we were talking about the light efficiency with an junction temperature of 25℃. However, due to cooling designs and influences from surrounding temperatures, it is usually higher than 25℃ in practices. That means, in real applications, the measured light efficiency will be less than the theoretical value. A theoretically 100lm/W LED chip used in LED highway applications may only have a real light efficiency of 60-70lm/W.
LHP is an advanced cooling technology for LED lighting products which has been recently invented by a technological company from Taiwan. This technique was first invented to replay traditional heat sink, which has well solved the problem mentioned above and dramatically increase the service life of LED chips. In order to prove the superiorities of LHP, thousands of LED chips were selected to take a 3-year special aging test (light attenuation test). During these tests, selected LEDs should take constant work for 12 hours per day. After 3 years, the measured light attenuation was less than 3%. It is estimated that after 10 years, the average light attenuation of these chips will be only 20%.
2) Cost-effective problem.
Presently, prices of LED chips were still in a high level, causing LED street lights cost much more than traditional street lamps. However, there are also some people believe that prices of LED lighting applications will drop into a much more reasonable level, for the reason that LED is a kind of semiconductor components and the continuous development of micro-electrical industry. At present, the highest light efficiency of LED chips is around 150lm/W. And it is estimated that after ten years, the light efficiency of LEDs can reach up to 350lm/W. Thus it can be seen that LED highway applications actually has huge potentials.