Short answer:

LED lights produce heat, but do not use heat to create light.

Long answer:

LEDs do not use heat to create light

Up until the advent of LED lighting, we solely depended on heat to create light. Fire, incandescent, and florescent light all use heat as their primary way to produce light. Incandescent light bulbs heat up a wire to a high temperature until it glows. Florescent lights heat mercury to a vapor then introduce the vapor to a phosphor, which produces light. On the other hand, Light emitting diodes (LEDs) use semiconductors with electron holes that when introduced to low-level voltage release energy as light. Before LEDs we ultimately had to find ways of making a light source hotter in order to increase its brightness or lumen output. Thanks to LEDs we no longer think of increasing heat, but decreasing heat for better efficiency and lumen output.

LEDs produce less heat

Though LEDs do not need to produce heat in order to create light, there is some heat produced in the semiconducting process. The difference is that the heat produced by LEDs is significantly lower than other lighting technology. This is why you often hear LEDs being cool to the touch and incandescent and fluorescent lights being hot to the touch. To show you the contrast, an incandescent light runs around 327 degrees Fahrenheit, CFLs are around 167 degrees Fahrenheit, and LED lights are around 107 degrees Fahrenheit.

Benefits of a cooler light

LED lights have many benefits, but what benefit do you get from LEDs being cool to the touch? When it comes to heating, ventilation, and air conditioning (HVAC), it means a significant reduction in cooling costs during the summer and reduced structural damage caused from ice dams, etc. in the winter. It also means no more waiting for your lights to “warm up” or burning your hand as you change out a light bulb… Ouch! Cheers to a cooler technology!