You often read that LED lights do not get hot, but technically that is not entirely true. LED light bulbs don’t get hot to the touch, but they do produce some heat, as all lights do.
All light sources produce some level of heat and LEDs are no different. However, the technology of LED lights allows for less heat creation and for the heat that does build up to escape.
So, how exactly do LEDs work and why are they not hot to the touch compared to other types of lighting technologies?
Read on to get the definitive answer on whether LED lights produce heat.
Why Do Lights Produce Heat?
All lights produce heat. So why is it that most LEDs are safe to touch while other lighting technologies are too hot to touch?
There are two reasons why a light source produces heat; energy efficiency of the semi-conductor and the production of infrared radiation.
You’ll often read that LED lights are more energy efficient than other types of lights such as halogen, fluorescent and incandescent lights. This has to do with how much of the energy consumed by a light element is transformed into actual light energy.
When a light source takes up electrical energy, some of this energy is transformed into actual light energy and the rest of it is transformed into heat and possibly infrared radiation.
Infrared radiation production is the main reason why other light bulbs become hot, which can, in fact, be intentional in some types of bulbs, such as the above chicken coup heat lamps.
Most LED lights do not produce infrared radiation so this already eliminates a large proportion of the produced heat. This leaves regular heat energy and light energy for LEDs.
This is also where the energy efficiency of an LED comes in. LED lights are able to transform more of the electrical energy into light energy compared to other light technologies
For example, the most energy efficient LEDs can convert up to 80% of the consumed energy into light energy. The type of LED technology used for home lights are not as energy-efficient, though.
How LED Lights Release Heat
No matter how energy efficient an LED light is, there is still some heat production. What sets apart LED lights from other types of lights is how this heat is released.
LED lights have a heat sink. A heat sink is a device that pulls heat away from the rest of the equipment and then releases the heat. On standard LED light bulbs, these are normally in the form of white ceramic sections or metallic ‘fins’.
On LED strip lights, or rope lights, a dedicated heat sink is generally not required as each light emitting diode is small and the light/heat output in one section is minimal.
LEDs produce less heat energy and the temperature released by the heat sink is generally less hot than other light types. However, the heat sink of an LED does get hot so be careful not to touch this part when the light is turned on.
Another reason is the materials used in an LED and the design of the fixture, which is why you should avoid cheap untested LED bulbs.
The quality of the heat sink determines how fast the heat is released into the surroundings. This is also influenced by the design of the LED and how conductive the materials used in the LED are.
Heat Production and Lifespan of LED Lights
How much heat LED lights produce and how energy efficient they are is the main reason why LED lights last longer than any other form of light bulb.
All lights produce an internal heat, also called the junction temperature of lights. LEDs are able to keep the junction temperature lower than other types of lights thanks to the heat sink.
A higher junction temperature of other light types is the reason why they have a shorter lifespan compared to LED lights. The higher internal heat affects the filament or structure of the light and over time creates damage.
The heat damage is why incandescent lights, halogen lights etc. fizzle out. Since the internal heat in an LED light is lower, the rate of damage is lower as well, resulting in a longer lifespan.
However, LED lights do not exactly die out. Instead, the junction temperature affects the efficiency of the internal structure which causes the LED to produce less light energy over time. This can be noticed more in LED tube lighting, as they’re often left on for 16+ hours per day.
The lifespan of an LED is measured from the start of use until the light starts to dim. So, technically an LED still works beyond its stated lifespan in the product description but will produce a dimmer light.