Picture of the Cree™ 100w LED daylight 5000k dimmable A21 light bulb, operating In living room lamp.

Review: CREE™ 100w LED Daylight 5000k Cool White Dimmable Indoor Outdoor Light Bulb




We have several of the daylight white CREE™ LED dimmable light bulbs situated throughout our home, and if they last as long as CREE™ predicts, they’ll pay for themselves at least three times over by the time they burn out.



We’ve used two 18-watt (100-watt equivalent) units as nightstand lights in the bedroom for over two years now.  These bulbs have run in that time, at least two hours per day, without burning out, and cost us only $13 apiece at Home Depot in 2013.  No bulb failures have occurred for us so far.  But a conventional light bulb would have required replacement several times by now!

Picture of a CREE LED Light Bulb, 100 Watt, the Front of its original carton.
CREE™ Daylight LED Light Bulb 100W, Carton Front

While a bit more troublesome to clean up, when used in enclosed fixtures, dust exposure can be minimalized by operating the bulb in approved enclosures.  This keeps the dust off of them, preventing overheating and premature burnout.  But though still somewhat pricey, these CREE™ 100-watt LED light bulbs are fast-becoming the sensible lighting choice for small and large homes alike.  Finally, they make a light bulb that you may never have to replace again.  It’s good.

Picture of a CREE LED Light Bulb, 100 Watt, back of original carton.
CREE LED Light Bulb100 Watt, Carton Back.

These bulbs sport a substantial metal finned heat sink just above their bases.  So they indeed operate with SOME heating.  But they don’t become nearly as hot to the touch as the incandescent bulbs, although you still want to be careful handling them; particularly when they’ve been operating for over a half-hour (the heat sink does grow too hot to handle).

They run silently, without buzzing, even when dimmed.  On radios, they’re also very quiet; generating no detectable interference on the AM shortwave frequencies most vulnerable to interference.

Picture of the Cree™ 100w LED daylight 5000k dimmable A21 light bulb, held in hand.
Cree™ 100w LED daylight 5000k dimmable A21 light bulb, held in hand.

Benefits, Features, Advantages, and Pros

Popular 100 Watt Brightness

These bulbs come in 40, 60, 75, and 100 watt (reviewed here) incandescent equivalent outputs.  Note that this rating IS NOT the amount of power that this LED bulb actually draws from the mains.  Rather, it expresses the amount of incandescent lamp light output that you get with this bulb.

Cool, Daylight White Light Output

The color temperature of this CREE™ LED bulb is 5000k, which is approximately the sort of light you see from the sky on an overcast yet bright day.

Much More Light per Watt

For the CREE™ 100-watt bulb, you get the same amount of light that an incandescent light bulb emits.  Yet you only pay for 18 watts!    The 100-watt equivalent CREE™ gives a hundred watts of “incandescent” light, while drawing only 18 watts.

Cooler Operation

With so much more of the consumed power going into actually producing useful light, and less to wasteful heat, LED bulbs radiate far less heat.  CREE™ says that their bulbs can be up to 82 percent more efficient than incandescent bulbs.

Long Life

They rate these at 25,000 hours average life expectancy.

Durable Construction

Does not break easily when dropped.

No Warm-Up Time

You get full brightness almost instantly upon LED turn-on.

Near Flicker-Free Light

At full brightness, we detect no perceptible flickers, no matter the ambient room temperature.  Even when dimmed to very low output values, flicker is a bit noticeable but not severe.  Further, how much the bulb flickers is also a function of the quality of the light dimmer itself.  If your dimmer is cheap, or produces a very choppy power waveform, you’ll get more flicker.  But these LED bulbs minimize that effect while still being dimmable.

Full Brightness, Even in Winter Cold

Like incandescent lighting, but not like compact fluorescent lamps, LED bulbs operate efficiently even in very cold temperatures.  The CREE™ units are no exception. you get full luminosity even when the room is freezing cold.

Less Brightness Decrease as Bulbs Age

As incandescent bulbs accrue more hours of operation, the internal filament evaporates over that time, and the metal deposits itself on the inside of their glass envelopes.  So, by the time the bulb burns out, its light output has significantly decreased due to the darkened glass that results from these metal deposits.  However, LED bulbs do not experience this source of light output reduction.  They retain much more of their new-state brightness, even when they’ve neared the end of life.

Dimmable

This line of CREE™ LED bulbs is fully compatible with standard leading-edge and rheostat type dimmers, remaining silent no matter how dim you set them.

More Constant Color Rendition Index (CRI) While Dimming

Unlike incandescent bulbs, whose color output changes from bright white to light yellow, to yellow-orange, to orange, to orange-red, and finally to deep read as you dim them down from full brightness, CREE™ dimmable LED bulbs do not change their color output nearly as much.  Even when dimmed to 10 percent of full brightness, you still get mostly daylight (5,000 K).  With these bulbs, you get just less bright but same-colored light.  The spectral output remains nearly unchanged, no matter how much dimming is applied.

Less Radio Static

Even during dimmed operation, since these LED devices draw less current through the dimmer, any leading-edge switching interference normally produced when dimming incandescent lamps, is way reduced with LEDs.

Less Dust Accumulation

With the lower heat output of LEDs, these bulbs run cooler, and so attract less dust and dirt.  The fine dust particles that do accumulate, do not stick as much to these, as they did on incandescent bulbs.

Nearly Omnidirectional

The radiation characteristics is very much like traditional incandescent lighting.  They give off light in nearly equal amounts in all directions except for directly underneath the bulb, toward the socket, although they radiate noticeable more from the sides than from the top; not a big deal when used in most lamps.

Lightly Frosted Glass and Plastic Envelope

Softens shadows and helps spread the light more evenly.

Ten Year Warranty

Picture of the Cree™ 100w LED daylight 5000k dimmable A21 light bulb, operating In living room lamp.
Cree™ 100w LED daylight 5000k dimmable A21 light bulb, operating In living room lamp.

 

Disadvantages, Cons, Problems, Limitations

May Not Fit in EVERY Light Fixture

The extra width of the heat sink near the base may prevent proper fitting of this bulb into some light fixtures and lamps.

Heavier than “Edison” Light Bulbs

Due to the internal support electronics and the rather massive finned heat sink, these bulbs can weigh up to several times as much as a traditional incandescent bulb.

Cleanup can be Difficult

Due to the tackiness on the globe part, dust can be harder than simply wiping off, to remove.  Also, the interior portions of the heat sink fins can accumulate dirt, particularly when these bulbs are deployed in dusty locations.  Too much “clogging” of these channels can spell premature bulb failure because when dirty, the sink does not as efficiently dissipate the component-damaging heat.  Improved heat sinking design (wider and fewer channels) may ease bulb cleanup problems.

Should Not be just Tossed Into the Trash

These bulbs, due to the electronics they contain, should be properly recycled.

Initially Expensive

Though CREE™ bulbs usually pay for themselves several times over throughout their entire lives, the initial cost of over $10  per bulb still turns away many consumers.  However, over the past few years, prices have fallen, with quantity deals becoming widely pushed.  So, we expect the higher single-unit prices to be temporary.

Picture of the Cree™ 100w LED daylight 5000k dimmable A21 light bulb, operating In living room lamp, with the shade removed.
Cree™ 100w LED daylight 5000k dimmable A21 light bulb, operating In living room lamp, with the shade removed.

Suggested Improvements

Get Rid of the Heat Sink Fins

Removing dust and debris from the small heat-flow channel spaces between each fin can be grueling.  Wider channels, or no channels, would allow for more complete and probably more frequent cleaning.  Hopefully however, increasing LED efficiency will reduce the need for such heavy metal radiators in future generations of this product.

Remove Outer Tackiness

This would facilitate rapid bulb wipedown.

Lower the Price

Many 100w LED bulbs these days cost less than half of what you pay for the CREE™ bulbs.

Our Rating

We’re pleased that CREE™ has created an affordable yet highly energy efficient product.  It’s now possible for the average consumer (our biggest population segment) to go green, without breaking the bank.  With the decade-long warranty, sub $12 price tag per unit, and shock-resistant construction, we’ve found the CREE™ bulbs highly durable, and given that warranty, we fear little over accidental failure due to excessive vibration.  The bulbs provide a decently full, natural-looking, 5000k daylight in most situations.

It’s great to see LEDs finally moving into mainstream lighting markets (they sure took their time getting there).   We believe that CREE™ has done an outstanding job ushering this technology into mass consumer markets.  They’ve helped convince many, by offering such a great product, that it really is worth the cost to upgrade from filament- and fluorescent-based lights to LED.  We’d therefore, rate this product at 94 out of 100, and if the price drops per unit drops several more dollars, our rating will certainly rise.



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References

Revision History

  • 2018-02-28: Revised tags and title.
  • 2017-02-14: Originally published.