LEDs have been around for a while—nearly 60 years ago GE scientist Nick Holonyak, Jr. accidentally invented the light that would replace incandescent bulbs. Holonyak was trying to make a visible semiconductor laser while his colleagues raced to invent an infrared laser. He lost the race by a week, but won the war against inefficient lighting when he created that little red semiconductor light.

In the years since, LED technology has improved drastically leaving many of its initial complications behind. Still, many of the myths surrounding LEDs persist.

 

“LEDs are too bright and too white”

There isn’t just one color or brightness level of LEDs anymore, so the bright white LEDs you may be imagining from 15 years ago are a thing of the past. Modern LEDs and control systems allow you to change color temperature and perceived brightness levels. If your LEDs are looking much whiter than the bulbs you previously had in their place, it may come down to simple overlighting. LEDs are measured in lumens—different to how traditional incandescent and fluorescent bulbs were once measured (in watts). Where it would take a 100-watt incandescent bulb to put out 1,600 lumens, it would only take an 8-watt LED to put out that same amount of energy and light. You should never replace a traditional bulb with the equivalent wattage in an LED.

 

“LEDs need time to warm up”

Not true! Unlike CFLs that come on slower or flicker, LEDs give full output, or ‘instant on’ from the time they’re turned on. They can also be switched on and off without shortening their lifespan.

 

“LEDs can’t be dimmed”

Sometimes the LED won’t be compatible with the dimmer already in place. This is often easily solved be replacing the dimmer switch, or finding a compatible LED—there are a lot out there! Traditional dimmers work by cutting down the amount of voltage that reaches the filament, but LEDs are designed to be either on or off, meaning the circuitry inside won’t be able to handle low current levels and will be damaged.

There are two types of light dimmers—leading edge and trailing edge. Leading edge dimmers are designed to work with high-wattage loads, making them great for incandescent bulbs, but likely not compatible with your LEDs. Trailing edge dimmers can control LEDs because they have a much lower-wattage range.

Dimmable LEDs have circuitry inside that allows them to respond to varying current levels or “pulsing” current waves—producing a dimming effect.

 


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“LEDs don’t give off any heat”

They do, but it’s minuscule compared to that of fluorescent and halogen bulbs. They do not give off radiant heat in the direction the light is being emitted—part of what makes them use less energy. They also don’t emit infrared light (IR), only visible light. You can’t see IR so it doesn’t add to the light’s brightness, it just makes the bulb hotter and uses more energy. In addition to being more energy efficient, the reduction in heat output allows LEDs to be placed in areas where traditional light sources would cause a problem.

 

‘LEDs are expensive”

This may have been true of first generation LEDs (in 1962, GE was selling Holonyak’s LEDs for $260 a pop!) but prices have come down a lot, and are often just slightly more than incandescent or fluorescent bulbs. Not to mention upfront costs are recovered quickly with energy savings.

 

“LEDs are bad for you”

Early generation LEDs were criticized for having too high a concentration of blue wavelength lighting, which, while helpful during the day for boosting mood, attention span, and reaction time, can interfere with circadian rhythm. (In recent years, we’ve been hearing about this as it relates to computer and phone screens.) Many manufacturers have solved for this by using violet light or coating the inside of bulbs to produce a warmer light. But, as stated above, nowadays there are virtually endless color temperature and brightness level options for LEDs, leaving it entirely up to you to determine how much blue light you want, and when you want it.

If you’re doing an LED retrofit, you’re most likely replacing fluorescent or incandescent bulbs. Fluorescent bulbs work by ionizing mercury vapor in a glass tube which creates UV light that is then converted into visible light by a phosphor coating on the inside of the tube. These lights are famously dangerous because the second a bulb breaks, you and everyone in your space has been exposed to the mercury once contained in that tube. Not to mention the other infamous virtue of the fluorescent: the headache-induing flicker.

Incandescent lights have a filament inside the bulb composed of the metal tungsten. When an electric current passes through the filament, it heats up to a temperature that produces light—and a lot of heat. If you’ve ever changed a lightbulb, you’ll have firsthand experience with this: scorched fingers and broken glass.

Unlike these traditional light sources, LEDs don’t contain mercury, lead, or other toxic materials and are completely recyclable.

 

“LEDs will need to be replaced”

Like all lightbulbs, yes, eventually you will need to replace your LEDs—but that time won’t come for many, many years. Most LEDs are rated for about 50,000 hours of use—approximately 50 times longer than an incandescent bulb, 20-25 times longer than halogen, and 8-10 times longer than a CFL. If your LEDs are on 8 hours a day, that means it will be about 17 years before you’ll need a replacement.

 

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