Ever since electrical lighting became a household staple, there has always been a concern about the safety of the light bulbs used. Anyone over the age of 50 can probably remember older, large bulb Christmas lights and the worry over overheated bulbs on a dry evergreen. Fortunately, as the science behind light bulbs has evolved, the safety of light bulbs in all forms has improved.
LED bulbs are energy-efficient and cost less than previously used lights, like incandescent and fluorescent (or CFL) bulbs. Every variety of light bulbs will generate some heat — that’s just how the science behind electrical lighting works.
Even today’s incandescent bulbs are engineered to deal with the heat generated in safer ways. Whether or not LED lights get hot is a subjective matter. They will generate heat, but they are designed to diffuse the heat.
Anatomy of an LED light
When most people think about a light bulb, they consider it an incandescent bulb, which is a fairly simple design. This bulb has a socket that screws into the fixture to make contact with the electrical current. Above the socket is a glass bulb containing a filament and inert gas that produce light when electricity is delivered to the bulb through the socket.
An LED light differs from this more simple design. While the bulb may look similar in some ways — primarily the shape — the way that the LED light operates is very different. Think of an LED light as more of a very small appliance with the sole purpose of generating light.
An LED light still has a metal socket that performs the same function — it delivers electrical current to power the light. Above the socket is a hard plastic heat sink that actually helps to dissipate the heat that is generated by the operation of the bulb.
The heat sink is hollow on the inside, which provides the housing for the circuit board that runs the light. This very small printed circuit board is there to control the connection of the electronic components. The circuit board is connected to a small disc that contains the LED chips.
In earlier versions of the LED light, there were fewer chips, which resulted in a narrow focus of light. This didn’t replicate the light that came from incandescent bulbs, so it made LED light bulbs less desirable. However, more recent versions have increased the number of chips to solve that problem.
To protect the LED chips and disburse the light in a more pleasing way, there is a rounded cap above the disc called a lens or a diffuser. These items could be shaped differently, but for aesthetics and to make transitioning from incandescent bulbs easier, the LED lights are designed to mimic incandescent bulbs.
How hot is hot?
Any electrical appliance will generate heat when it is operating, and LED lights are no different. The good news is that because LEDs use much less electricity than other light bulbs — like incandescent, halogen, or fluorescent —they also generate less heat.
Knowing the anatomy of your LED light bulb is important because there are parts of the bulb that are safer to handle when it gets hot. You should always turn a light off before taking out a bulb, and if possible, keep the light off for a while to allow the bulb to cool.
If you can’t wait for the LED light to cool, take care when touching or removing it. As its name indicates, the LED light’s heat sink is there to dissipate the heat. This will be the hottest part of the bulb, so never touch the heat sink if you need to remove the bulb.
Some testing has indicated that the heat sink can get as hot as 140° to 210° F! The diffuser, or the top part of the bulb, is usually not as hot and is the best place to touch your LED bulb.
The temperature of the surrounding environment can affect your LED lights, so the same bulb in two different fixtures may vary in how hot they get depending on the room temperature. LED chips can be affected by an overheated environment, so consider where they will be used.
Some lower-cost LED lights may overheat — and malfunction — if they are used in a closed fixture. An example of this would be an enclosed dome as you would find in many ceiling fans.
While they do get hot, the heat generated by LED lights is low and gives everyone one more reason to make the conversion to LEDs. LED lights generate about half the heat of incandescent or halogen bulbs, and about 20% less heat than fluorescent bulbs.
Their low-heat properties make LED lights ideal for environments where a light bulb that produces less heat is desired. A smaller room, closet, or home gym would be great places for LED lights.