Incandescent and halogen convert only 5% of energy into visible light, roughly 95% of energy into heat, LED converts 40% of energy into visible light, still 60% of energy into heat. Many customers may believe that LED will never produce any waste heat because everybody is saying that it is high-efficient.
LED is one kind of semiconductor component, the basic unit in LED is transistor, same as the transistor in CPU in laptop. As we know that CPU in laptop needs a copper heat guide with a mini-fan to dissipate heat, LED also needs to dissipate heat by heatsink. If CPU temperature gets too high, the laptop speed will slow down, if LED temperature gets too high, the efficiency will decrease.
“But why I feel almost the same temperature as halogen when I take off the LED track light head from the rail?” Some customer may have this question. Firstly, LED track light head consumes much less power than its halogen equivalent, for example, 6.5w LED track light head, with 500-lumen output, is an equivalent of 50w halogen light bulb, 16.5w LED track light head, with 1200 lumen output, is an equivalent of 75w halogen light bulb. Even the same amount of heat is generated, LED is more efficient with less power consumed. Secondly, heat is dissipated only by conductance for LED, for halogen, only a small part of heat is dissipated by conductance, a large part of heat is dissipated by radiation, if we consider radiation heat, LED is even more efficient.
To keep LED modern light fixtures working efficiently and durably, we must help LED to dissipate the heat out, that’s why we see different kinds of heat sink for LED light. In the case of LED track light head, the heat sink is the aluminum cylinder. The key is keeping LED working at an acceptable temperature, so the key temperature is LED working temperature, instead of the temperature of the heat sink. If you touch the LED light, actually the heat sink of the LED light, and feel it’s hot, it maybe indicates that the heat within LED is successfully dissipated.