LED FAQs

Get the facts, then prepare to be enlightened.

1. How long do LEDs last and what is the degradation/failure?

When operated properly, LEDs do not burn out like normal light bulbs, but rather dim over time. The current standard for rating the “lifetime” of an LED is the point at which the light produced is only 70% of the initial value. Under proper operating conditions, LEDs can have a lifetime exceeding 50,000 hrs (> 6 years of continuous operation.)

2. Why are LEDs so energy efficient?

Light-emitting diodes are a special type of transistor that uses the electricity to create an electric field inside the tiny chip. This electric field enables the very highly efficient creation of light inside the chip. Unfortunately, due to tiny defects at an atomic level and optics of packaging surrounding the chip, some of this light never escapes to the outside world where we can see it. Today, the best chips are producing about 30% of their theoretically expected efficiency, but many industry experts are confident that this value could be increased to 60% or greater in the years ahead.

3. How do I change the LEDs?

For high-quality products, the LEDs will last the life of the fixture. Light-emitting diodes do not burn out, but rather very gradually get dimmer. A typical LED light, used 24 hours per day, will have 70% of its initial output after 6 years.

4. Cost/payback?

Currently, LEDs are more expensive than traditional light sources, but the performance of the LED chips themselves continuously improve at about 30% per year at a fixed price point. While many factors contribute to the payback of this additional up-front investment, LED lighting uses 50% to 80% less electricity than conventional sources and enjoys a greatly enhanced interval between replacements by a factor of up to 20x.

5. Why are LEDs so cool?

Light-emitting diodes produce only visible light. Most conventional lights such as filament bulbs produce the vast amount of their light in the infrared region of light, which humans cannot see but is readily absorbed by most objects, thus producing a “warming” effect. Light-emitting diodes do produce heat, but with proper engineering and design, this heat is easily dissipated in a manner that is unnoticed by the user of a light.

6. Are all LEDs the same?

While all LEDs operate under the same general principle, they can vary greatly in their performance and lifetime based upon the design, quality of materials used in their manufacture and know-how of the manufacturer. Leading companies manufacturing chips for Permlight have extensive experience stretching more than a decade to a time when relatively few companies were investing in LED technology.