Tech Theory

LED Home Lighting…Ready for Prime Time?

This morning, TechieInHell asked about your preferred type of home lighting. Since I work for a company that manufactures LED vehicle lighting, I had previously written an in-depth look at LED home lighting for my employer’s corporate newsletter. I present it here to AT readers in a slightly revised form.

Most people are aware of the advantages low-voltage light emitting diodes (LEDs) over incandescent lights for vehicle lighting and flashlights: longer life, vibration resistance, lower power requirements, less heat; the list goes on and on. Meanwhile, the bulk of the general public has converted at least some of their incandescent home lighting to fluorescent tubes and integrated compact fluorescent lights (CFLs) in order to save money on energy and help protect the environment. Far fewer have considered LED home lights, which are available commercially but remain more of geek/techie niche. Higher-voltage LEDs offer many of the advantages listed above, but some drawbacks remain. Are they ready for mainstream use?

LED lights are not practical for all uses, but self-contained LED “light bulbs” designed for use in home light fixtures are an attractive option worth considering. They are 30% to 50% more efficient than fluorescent bulbs, last much longer, and are much less prone to breakage. A typical residential LED room light can theoretically run six hours a day for twenty years. Granted, that is a maximum, under ideal conditions. Many bulbs will fail far sooner than that, mainly due to the failure of the internal wiring or electronic circuits, rather than the diode itself “burning out.” Even with these limitations, a real-world service life of seven to ten years is a reasonable expectation for LED lights. Also, most LED lights last about as long whether they are left on continuously or repeatedly turned on and off. The lifespan of fluorescent lights decreases significantly when they are switched on and off quickly and frequently, such as in a closet or an automatic garage door opener.

This chart is based on data that is now 3 to 4 years old.
Since then, LED bulb costs have gone down and energy costs have risen.


The first commercial white LEDs, released in 1996, exhibited poor color temperatures, often appearing too blue or too green. Today, many LEDs can be configured to generate light that is practically analogous to natural sunlight, and that natural color temperature is one of their advantages over fluorescent lights. Unlike fluorescent lights or natural sunshine, LEDs emit no ultraviolet light. This makes them ideal for spotlighting valuable art, artifacts and furnishings without the risk of fading, cracking, or other unwanted effects from radiation. LED lighting also benefits individuals with medical conditions that cause sensitivity to ultraviolet light and those who notice fluorescent lights’ potentially annoying flicker.

LED bulbs are safer. Unlike incandescent bulbs, LEDs run cool enough to eliminate fires and burns on contact, and don’t contain the hazardous mercury vapor found in fluorescent lights. While LED lights do have circuit boards containing hazardous metals and should therefore be disposed of properly, the hazardous material is encapsulated and does not present the health risk of mercury exposure from a broken fluorescent tube.

So why doesn’t everybody use LED lights in their home? Unfortunately, there are some significant issues with LED lights. One overwhelming drawback is cost. LED bulbs can cost forty times the cost of an incandescent bulb of equivalent output, and twenty times the cost of a comparable CFL. LEDs are cheaper in the long run (see chart), but at up to $120 per bulb, people often don’t have the up-front cash to invest in a large number of LEDs all at once.

Also, LEDs are not technologically ready for every application. Compared to CFLs and incandescent bulbs, the individual diodes in LED bulbs cannot generate nearly as much light. A clear-glass, 200-watt incandescent bulb puts out nearly 4000 lumens of light. The brightest household LED bulb can generate less than one-fourth that amount. LEDs are also directional, aiming all their light in one general direction. Because of this, bulbs that use the highest power diodes are usually designed as directional floods. While this helps them make the most efficient use of that output, it also means that they leave corners dark and do not provide the “all-around” glow most of us are comfortable with. LED bulbs that are designed to mimic omni-directional bulbs must have many smaller diodes mounted to a cylinder, pointed in every direction. The high number of diodes required drives up the per-lumen cost of these bulbs.

High-powered LEDs can generate enough heat to damage their circuitry, and are therefore equipped with some type of integral passive cooling device. This is usually a large metal heat sink, sometimes with cooling fins. The resulting bulb unit can be too large or too heavy to work in some light fixtures.

There are a wide range of LED bulb brands and types on the market, but local hardware and home stores will probably have only a limited selection, if they have any at all. The best selection and prices can be found at “techie” websites such as cyberguys.com, thinkgeek.com, and vendors that specialize in high-tech lighting such as ccrane.com.

Surface-mount flood fixture with Cree-knockoff 7-LED Edison bulb installed.

When I first installed LED bulbs at my house three years ago, energy savings was only a tertiary reason for the switch. Our house is equipped with two external floodlights in the second story eaves over the driveway. They are about 25 feet off the ground, and require an extension ladder to reach. I had long ago tired of constantly dragging out the ladder to replace the PAR 38 reflectorized incandescent bulbs – which I always seemed to be out of. After one fixture’s socket became so corroded I broke the bulb trying to remove it, the remaining bulb burned out yet again. I gave up and the floods remained inoperative for over a year.

Finally ready to tackle the task of replacing the lights, I wanted to fix the problem once and for all. I bought two new flood fixtures and went shopping for LED bulbs. Everything I found was not bright enough, too expensive, or not suitable for outdoor use. I finally bought two PAR 38-style Edison LED floods from an Ebay vendor for $94, including shipping. (Remember, this was in 2008; prices have come down since.)

When I received them, I was amazed at the heft and the impressive workmanship of the massive aluminum frame. Each bulb is equipped with seven whopping 3-watt diodes that pump out 700 total lumens, roughly equivalent to a 60- or 70-watt incandescent floodlight. Installation was straightforward, but I was glad I had purchased new light fixtures, as the LED floods would have been too large to fit inside the hood of the old lamps. As it was, the LED floods were so heavy they rested on the lower edge of the hood. If I had tried to install them in a fixture with nothing to support the bulb, I would worry that their weight might break the bulb bases out of the lamps.

I’ve been very pleased with the new lights. The color is rather “cold,” almost a bit blueish, but that is to be expected from the highest-output diodes and certainly not bothersome for outdoor floodlights. Their narrow, 30-degree pattern was just right for illuminating the driveway from so high off the ground. They’ve worked flawlessly in -8° to +100° F weather (-22° to +38° C). As energy prices rise, the fact that they now consume only a third the energy of the old lights becomes more and more attractive, too.

But, to find out if the switch to LEDs is really successful, I will have to wait and see if I have to climb that extension ladder over the next seven to ten years. But so far, so good.

  • tonyola

    A quick peek at Home Depot shows Philips 60W-equivalent LED bulbs going for $40 each. That's about 80 times as much as a 60W incandescent bulb at the local supermarket. They have a ways to go yet.

    • Same price on Amazon when I checked it out yesterday. Still too damn expensive for me, even with future savings.

      • P161911

        Really hard to swallow paying more for the bulb than the lamp/fixture.

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  • Charles_Barrett

    In configuring external lighting for the guest house we've built on the family ranch in Cornville, Arizona, the Yavapai County Planning Commission requires "Dark Sky"-compliant fixtures for all new construction, to minimize light pollution from rendering nearby Lowell Observatory less effective. Our front and rear porch lights may direct light downward only, not upward or to the side. The tight focus of LED lighting would work wonderfully in the pursuit of keeping the sky clear for optical observing.

  • Curly

    The problem I have with LED lights is the same one I have with CFLs: (despite using CFLs in nearly every fixture in my house) I don't believe the quoted lifespan. I'm sure that on average, certain elements of these lights experience wear 8 (CFL) or 50 (LED) times more slowly than incandescent bulbs, but whether due to environmental factors, power fluctuations, or the high frequency yapping of my noisier dog, I haven't experienced nearly that large an increase in replacement interval. 60k hours is a long time, man. Your house could burn down, there could be an earthquake, a flood–it's just a long damn time for any relatively cheap consumer good to last.

    A thought experiment: would you pay 8x as much for a car with a drivetrain (and hell, suspension, tires, electrics… the works!) guaranteed to last 5 million miles? Even if it looked and felt just like a G37 and got 150 mpg?

    That said, you're probably right that we're at the tipping point for LED practicality–and Charles Barrett's example of the *benefits* of narrow beam lights is a good one.

  • The savings is very impressive, but the cost of entry is quite prohibitive. I would love to be an early adopter, but, to get bulbs for our house, it would be a very, very steep investment.

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