Yes, LED lights can die, but their lifetime is comparably much longer than standard halogen, incandescent, and compact fluorescent lamp bulbs. A common rule of thumb is that an LED bulb has a life expectancy of 50,000 hours (though mileage may vary between manufacturers), or in other words if you used an LED light string for 12 hours per day it would theoretically last about 11.4 years. That’s quite some time before an LED would need to be replaced!
LED Lights Last Longer
“First, the latest LED bulbs last up to five times longer than traditional fluorescent bulbs, and nearly 50 times longer than incandescent bulbs. Additionally, new LED light bulbs use half the electricity that compact fluorescent bulbs use in the same allotted time, and less than a quarter of the electricity used by incandescent bulbs,” according to a research report prepared for the Worcester Polytechnic Institute.
This energy efficiency is an important matter when considering why LED lights don’t die as quickly as their counterparts — slight tangent, but it relates back to the second law of thermodynamics, which states that with each energy conversion from one form to another, some of the energy becomes unavailable for further use, according to an energy education program from the University of Wisconsin-Stevens Point.
Translated to light bulbs, the electrical energy that powers the bulb is partially converted to visible light and the rest is emitted as heat. How lights are made will affect light efficiency and longevity, partially because that heat will degrade the materials that make up the bulb. Different types of bulbs output different levels of light efficiency and lose different amounts of energy as heat.
Incandescent bulbs typically only convert 5 to 10 percent of the input electrical energy into visible light while the rest is radiated as heat. Compact fluorescent lamps are 20 percent efficient. Comparatively and impressively, LED light bulbs are around 90 percent efficient.
While incandescent bulbs have a filament that wears out and breaks, LED lights generally just get dimmer until eventually they do not produce a useful amount of light. This is called “lumen depreciation” and it determines the overarching “lifespan” of an LED light, which is technically when the light output decreases by 30 percent.
Heat Affects Light Lifespan
Heat still affects the material of LEDs.
“Since LED lighting systems don’t radiate heat the way an incandescent or CFL light bulb does, the heat produced from the power going into the product must be drawn away from the LEDs. This is usually done with a heat sink, which is a passive device that absorbs the heat produced and dissipates it into the surrounding environment. As a result, this allows the LEDs to keep from overheating and burning out,” according to Life of LED-Based White Light Sources.
Thermal management is an important factor in LED performance over the lifetime of the product. The higher the temperature at which the LEDs are operated, the more quickly the light will degrade, and the shorter the useful life will be, according to Energy Star.
Structurally, an LED works by passing electrical energy through a microchip, thereby illuminating the small light sources within it to produce visible light. A heat sink will be located near it, but could vary from manufacturer to manufacturer.
The lifetime cost savings of switching from incandescent to LED light bulbs is another reason to consider LEDs over incandescents, as was discovered in one article published by the North Dakota State University Extension and Ag Research News.
“[One] business replaced 100 65-watt incandescent bulbs with 8-watt LED light bulbs, which saved 5,700 watts of electricity while the LEDs produced the same amount of light,” according to the news release. “The business saved approximately $172 a month in lighting energy savings, according to [Russ Schell, owner of RJ Energy Solutions of Fargo]. The total savings was even more because air conditioning was not required to remove excess heat produced by the incandescent bulbs during the summer.”
With all that being said, it’s critical to think through a replacement strategy for LED bulbs that diminish in output over time. The good thing, though, is you can probably be a bit more relaxed with making that schedule. They’re not going to burn out any time soon. In the event you have light strings you’d like to run continuously for that long, LED Lights Unlimited has LED light strings with removable bulbs in case of burnout.
Just think about the daily use, multiply that over over time, and mark it on your calendar 50,000 hours from now. Simple enough, right?