Lifetime isn't even my #1 concern with LED bulbs. It's strobing/flickering.
I film all the LED bulbs I buy in slow motion at 240 fps with an Android phone, and play the movie back on a PC with mplayer using the dot(".") key to move frame by frame. Here is a shot I made comparing 2 brands of LED bulbs: https://youtu.be/QbenId_F2RQ (Edit: yeah you don't have to transfer to a PC, just playing back in slow motion on the phone will still show the effect quite well.)
It's amazing how I find this way that most (but not all!) of LED bulbs flicker with a strobe effect at 120 Hz (frames alternate between bright and dim) because they have crappy power supply designs that fail to smooth the A/C voltage. As a result they flash one time during the positive phase and one time during the negative phase of the 60 Hz A/C mains frequency.
I find this unacceptable. Although not too noticeable in normal conditions, a 120 Hz strobing light is definitely noticeable when your eyes move or track an object illuminated by the bulb.
In my experience, Philips lightbulbs are one of the few brands that don't have this flaw because they take care of converting AC to a stable DC voltage internally. In fact they are advertised as such: https://www.amazon.com/dp/B07CFRCGKC "COMFORTABLE LIGHT: Our products meet strict test criteria including flicker, strobe, glare and color rendition to ensure they meet EyeComfort requirements"
LED flicker could prove harmful or fatal if you work with anything that rotates or reciprocates.
The rotating / reciprocating mass may appear stationary at some RPM.
Just a reminder to only ever use incandescent or halogen lights around machinery you can touch while in operation: drills, lathes, mills, slotting machines, etc.
Yeah, please don't rely on your eye sight to tell you if a tool is operating. Every time a tool is running you should know it is because you started it to a specific purpose.
Before you start a tool you should act out your planned motion. Then start the tool and only perform this motion. If something changes and you cannot complete the motion, stop the tool immediately. Following this and a few other safety tips I've operated power tools for years without incident and I'm legally blind.
Okay, but, say you've configured the tool wrong and now it's destroying your work. You stop the tool. How soon is it safe to grab your work away from the work surface—i.e. when will it go from "it's too dangerous, let it keep destroying the work" to "it's now slow enough to pull the work off of the tool while it's still—slowly—running, to save the work from further damage"? That's a thing you have to figure out with your eyes (and ears).
Just how likely is this to happen though, it would have to be the only light source and be flickering with exactly the same frequency as the machinery is traveling at (which i assume for most devices varies a lot).
Not saying it can't happen but it does seem stupidly hard to achieve.
It's not true that it has to be the only light source. All of the light sources have to be the same type and on the same circuit, which is fairly common.
Many AC motors are synchronized to the frequency of the power line, by the same principal that turbines in the power grid are. So 60hz AC often means 30hz = 1800 rpm motor, and 59.8hz AC means 29.9hz motor. So if you have LEDs with a half bridge rectifier and your machinery is 180 degree rotationally symmetric, it will appear to not be moving, even if the line frequency fluctuates.
Pretty common, about as common as the wagon wheel effect in 24fps film movies. In just the same way, the item can appear to stop, run slow, or run backwards, just as with film. No it does not have to be the only light source, just the nearest one to the machinery.
Fluorescent tubes are most noticeable, LEDs a little less. Tungsten or Halogen are the only sensible option for workpiece illumination.
Or, of course, just use a LED that properly smooths out the DC. It's not hard to do, and a quality LED manufacturer should get this right. The only excuse for flickering is a cheap LED that cuts cost for circuitry.
Oh I agree, but a surprising number of LED bulbs have some degree of flicker, even from those makes you might expect to do better. A purpose made work lamp should get it right though. Hopefully. Maybe.
For my hobby stuff, I just bought a couple of spare halogens that should see me out.
I would imagine there's a higher-than-average chance of this because most AC motors are definitely syncronized with the 60hz (or 50hz) AC source. There's a chance the lights might also derive from this.
> There's a chance the lights might also derive from this.
If the light is flickering it's absolutely guaranteed that it's derived from this.
But it's hard to imagine a lightbulb that emits a short enough pulse of light to make something look stopped. Even an absolute garbage one-way rectifier will be emitting light more than a quarter of the time. That can make a tool look odd, but it won't make it look still.
If the light is flickering it's absolutely guaranteed that it's derived from this.
Not necessarily. If it's a 50/60 or 100/120 Hz flicker then yes, but LED lights with a cheap switching power supply might still flicker at the switching frequency, which could be say 400Hz or something.
You have to be intentionally wasting money to put in a transformer big enough to handle 400Hz, and once you get into the lots of KHz where a supply like that is happy I think your "please don't explode" capacitor on the transformer is enough to prevent flicker.
It doesn't have to be going the exact same speed, a multiple would do the trick too. It can also be dangerous if it's close to the same rate since it can then look like it's going slower even if not stopped.
This is uncommon but not rare. Have you ever seen wheel blur or other artifacting of such? It's very easy to make happen artificially under controlled conditions which means it can't be that hard to happen accidentally.
Edited to add: Have you ever heard of a timing light for an engine? This works exactly the way you are describing.
Timing lights for engines work this way for clarity: The distributor on an engine has a spinning rotor and a number of points (one for each sparkplug) on the outside the circle the rotor forms while spinning are a series of contacts across which electricity jumps to send voltage to the spark plug.
The timing light is then pointed at the flywheel on an engine, which has numbers or marks stamped into it. Each time the spark plug fires the timing light (which is hooked into that same current via induction) lights up for a brief amount of time to show at what timing offset the engine is currently at. (this all happens at hundreds of rpms a minute).
The effect might not be rare but getting hurt by it is incredibly rare. Machines produce noise and vibration. Nobody is going to be fooled and try to pull a moving part out of a lathe because of some LED lighting except in the most exceptional or bizarre circumstances.
Machine shops are very loud (plus you'd be wearing ear protection) and a lathe/mill that vibrates noticeably is either broken or incapable of performing the very task its designed for.
Nobody? That is a high bar. Mechanics tend to be pretty cluey, but for the effort of getting proper lighting why nobody should be taking that sort of risk. Sight is one of those fundamental lets-feed-in-useful-information sensors for keeping situations safe.
Most people spec'ing out machine shops are not experts in lighting other than more = better. This is a really, really low risk we're talking about. Like basically the stars have to align for someone to get hurt.
Are there any statistics on this? That seems like the obvious way to settle this issue.
So far, the discussion sounds like it's a theoretical possibility. If it's a real possibility, then it's something that should have happened a number of times.
It's easy to miss those signs too. It's common to have earmuffs and sometimes a dust mask on when using power tools, and power switches often don't clearly indicate state. Many start/stop control boxes don't have any visual indication of state at all.
Someone might hear the noise and feel the vibration but think something is broken inside because the drill isn't rotating. I'm not sure exactly how that would lead to an accident but it might.
Multiple light source of the same general characteristic (don't even have to be the same type of bulb) may produce this result.
The rotation frequency would have to be close to a relatively simple multiple (or fraction) of AC frequency but the way electric motors are contstructed if the piece is directly connected to a motor it is very likely it is true.
I only buy Philips bulbs for this very reason, or from brands that advertise being flicker-free. With iphones, slow motion mode also makes the flicker very visible without the need to transfer to a PC.
Visible light impulses influence brain wave patterns (e.g. [1]), and it might not be beneficial to look at pulsed light with a frequency that is not well researched.
Same thing with screens, most LEDs are dimmed with pulse width modulation [2], so they flicker at most brightness levels except the very brightest one. Some iPhone X users claim they get a headache when looking at the phone at the lowest brightness setting (OLED is even worse in that regard than LED, IIRC).
Very good points here, I would add that 99% of the monitors are also flickering when you dim their ligth. This is why i started using the iris[1] app on my laptop. Keeping the brightness at 100% in the hardware settings will eliminate the flicker, then iris dims the lights from your graphic card. I can work without eye oain thanks to this method.
- [1] https://iristech.co
I had a small bag of Chinese position light LED T10 lamps for my car my dad had given me. I would change them every three to five months because the LEDs would burn out. Getting sick of sticking my hand in narrow spaces to replace the lamps, I ordered two Philips Xtreme Vision 4000K T10 LED lights. They've beeen running flawlessly more than a year now.
>Some iPhone X users claim they get a headache when looking at the phone at the lowest brightness setting (OLED is even worse in that regard than LED, IIRC).
And on iPhone XS this is even worst. I wonder if there are any solution to PWM problem.
What I've found to help weed out the worst of the worst is to only buy dimmable versions of the bulbs. They cost more but because they have to support dimming they're almost required to have a better power supply to handle the usual triac based control that most dimmers have.
The worst bulbs I've personally seen for flicker were dimmable ones.
The non-dimmable variant from the same range had no noticable flicker.
Price paid also seems to be no indicator of quality – I've had premium LED bulbs from major makes, bought from a reputable wholesaler, that have died after 6 months within days of each other.
I've had cheap no-name imports that have lasted years and had no flicker.
A lot of "dimmable" LEDs are actually shifting the flicker pattern to dim the light (shorter on phases). This is for LEDs where the user dims per remote control. OP was talking about the older "legacy" dimming, where you have a wall-mounted knob that reduces the current. Works well with incandescent bulbs. But only few LEDs support this. If they do, their internal power converter likely won't flicker, because of their more thought-out converter?
However, there are also LEDs that support legacy dimming, but again translate less current into different flicker patterns...
I've been trying to switch to all-LED in a home with lots of legacy dimmers and it's been painful. Even on circuits where I've replaced older dimmers with new Lutron CFL/LED dimmers, I get flicker.
In other places I don't have dimmers but have low-voltage (12V) cans. Lots of flicker issues there too, presumably due to the 120->12V transformer at the can.
And then I have a light fixture that's both dimmed and a custom 12V setup. I've given up on finding a working dimmer/LED bulb (MR16 GU5.3) there. Probably need new 12V transformers?
I'm really happy to see you post this. Everyone else I've brought it up too just says I'm crazy. I might be crazy but not about the damn flickering/strobe.
Especially when my dog bounces around it looks like she is in a strobe light. I did a couple of videos of it just to "prove" it in some fashion.
I use a salt shaker and pour salt onto a plate - if I can make out single falling grain of salt on the way to the plate, I know this light source is not healthy for humans.
A metal working friend told me recently that in Australia we're not meant / allowed to use fluorescent lights above lathes, as the flicker can disguise movement.
Yeah gas discharge lamps (CFL, neons, halides) will flicker at twice the mains' frequency on a single-phase circuit, makes it very dangerous to use them as e.g. factory lighting. You can mitigate that by using 3-phase power supplies, high-frequency controller, or by supplementing the basic lighting with incandescent bulbs around machinery.
The stroboscopic effect is really fun right until you're in a place with lots of moving parts at a multiple of the strobe frequency.
OTOH it's also used to fine-tune engine timing and such: set a stroboscope at a fraction of the frequency you want, the engine is properly tuned when everything looks completely stopped. Makes it very easy to notice mistiming.
Some turntables include a strobing light and rings of dots around the edge for different speeds. If it's spinning at the correct speed the corresponding dots will stand still.
Absolutely - the way he described it sounded like a horrendous accident waiting to happen, especially for smaller / home shops where the operator may not be aware of the problem. He was under the expectation that LEDs solved this problem, though he is using drop-in LED tubes that may have some better persistence through the off-cycles.
I do some occasional wood-turning, but usually augmented with ambient daylight - along with the dubious safety advantage of having a very noisy electric motor.
Plus I'm old enough to have used a timing light hanging off a distributor on my first car. Try explaining that to the kids of today. ; )
Shaking a hand with fingers spread out somehow works to spot flicker. If the light source flickers, you see oddly sharp finger positions in the air. It's not the most sensitive or easy to interpret method.
I calculated the airspeed of a rubber band this way once! My coworker shot a rubber band in my direction. I noticed three “shadows” of the rubber band as it passed by the CRT.
The CRT was a 17” running at 60hz. The rubber band sailed past in the span of about 2 screen refreshes, so it traveled that distance in 2/60 of a second. Distance was easy to calculate by the Pythagorean theorem or by holding a ruler to the screen, I forget which.
In the huge HN thread here¹, yeutterg mentioned² their Bedtime Bulb:
> “I am on a mission to make lighting healthy. That's why I made Bedtime Bulb: https://bedtimebulb.com/ It has the lowest flicker I've ever seen in a bulb form factor—even less than those claiming to be "flicker-free."”
In addition to that, a few other database sites that test for flicker were mentioned here³.
I've tested a bunch of bulbs for flicker with a handheld flicker meter and with a photodiode connected to an oscilloscope. It's funny that some of the bulbs out there claiming to be "healthy" have terrible flicker. One product from Soraa was flickering at over 50%, almost as bad as the cheapest/worst LED bulbs you can buy.
I don't have a database, but I can say that most (but not all) filament designs are terrible for flicker--ours is an exception. Philips products seem to have gotten worse in quality over time, probably to remain competitive, but they are better than the worst. Ikea's stuff is pretty good overall. I don't have a consistent recommendation for low-flicker general lighting right now, as every brand has good and bad products.
Thanks to GP for the links, I completely missed that previous thread!
And, yeah, I tried that Soraa healthy bulb, and it was shockingly bad, given how it was advertised. Even the regular Soraa bulbs were disappointingly flickery, though less so. Also, just looking at the pattern it makes on my phone's rolling shutter, the wave is quite saw-toothed, and I wonder if that makes it worse? I have some Ikea candelabra bulbs which were always pleasant, and I was surprised to see they also left quite a visible flicker pattern on my phone, though much more sinusoidal/smoother.
It's a shame about the flicker in the Soraa bulbs, since the colors really did seem nice.
The Soraa bulb looked pretty sinusoidal on my scope when I tested it briefly. But it's a lot of flicker regardless.
What's interesting is that the bulb seems to have a nice build quality (from the outside, I didn't open it) and is quite heavy. I suspect they are putting a BIG heatsink in there, as violet pump phosphors tend to degrade quickly.
The other thing that irks me about this product is the "zero blue" messaging. Yes, I can confirm the spectrum looks like what they are advertising, with a peak around 415nm, almost nothing between 440-490nm, and then all the rest of the colors from green to red.
But, green light is just as bad as blue for sleep! The ipRGCs are sensitive to both blue and green (up to around 600nm) This bulb has a lot of green, more than a lot of other light sources. It also has a very unpleasant greenish color (IMO) and low-ish CRI, around 78 on the bulb I tested.
Is it better than a normal 600lm bulb for sleep? Yes. Is it novel? Yes. Is it good in practice? I don't think so.
That's right, the Soraa Healthy was very green! So, even without the flicker, the fact that it makes everybody look like undead zombies would be reason enough to disqualify it as a bedroom night light.
Haha, totally agree! If you are still in the market for a low-blue, low-flicker solution, may I humbly suggest a look at my product, Bedtime Bulb [0]? I know I basically bashed the Soraa product here, but not without technical justification.
what does that mean? Duty cycle is 50%, frequency at something Hz? Not being snarky - curious whether there is some kind of standard that your tool compares against.
A duty cycle 50% (or any percent really) isn't bad in itself, it's the frequency that is the culprit. Too low PWM freq and you'll notice it.
When I refer to % flicker, I am talking about the modulation % as defined by IEEE 1789-2015 and some documentation from the Illuminating Engineering Society [0][1]. More correctly, invisible flashing is known as the stroboscopic effect or phantom array effect.
Two factors are often used to describe flicker for lighting:
- Modulation %, a.k.a. % Flicker [The height or modulation of the waveform, formula is 100% * (A - B) / (A + B)]
- Frequency [self-explanatory]
Flicker Index is also used (refer to [1] page 7 for more info) but rarely.
Duty cycle is not considered relevant, as you mentioned.
Some tools designed to measure lighting, such as my UPRtek CV600 [2], spit out % flicker, frequency, and flicker index, in addition to a bunch of spectrophotometry metrics. It's also pretty easy to calculate the modulation % with an oscilloscope and photodiode, it's just Vp-p / Vmax.
IEEE 1789 [0][1] roughly says that the higher the flicker frequency, the more acceptable it is to have a high modulation %. If you look at the graphic on [1] page 18, you can see this relationship. The white area is considered unsafe, the yellow area is "low-risk", and the green area is "safe." I don't 100% agree with this personally, as most incandescent lighting, with around 6-11% flicker at 100-120 Hz, would fall into the unsafe or low-risk category. But the Soraa product is definitely in the unsafe category.
For reference, I plotted my product (Bedtime Bulb) against an incandescent A19, Lighting Science's Goodnight A19, and Soraa's Healthy A19 on an IEEE 1789 graphic [3] with a Python tool I'm developing, Beautiful Flicker [4]. You can see that this incandescent, measured around 10%, is on the border between unsafe and low-risk by this standard.
I don't think I could have wished for a better answer, thank you. Love it when a new area opens up to me like that! While I'm not active within lighting per se, some of our customers are, and this will help me understand the complexities of their products better. So, thank you, it does help!
This concerns me. About a year ago I went onto a website and ordered 56 led bulbs for my entire house and thought I got a fairly good deal. They worked seemingly well but my eyes always felt strained when under them. Just took my iphone and can definitely see the flicker with slow motion. And when I look at items as I move my head across the room I feel like I can see it as you say and never really knew what I was experiencing before. As someone who always talks about having sensitive eyes to light I am definitely not happy about this and am now thinking about buying flicker free bulbs. Thanks for sharing.
I usually just move my phone really close to the lightbulb and watch the live camera view. At a certain distance/angle you can usually see the flicker as banding across the screen.
I saw a test in a Swedish newspaper lately that showed IKEA's cheapest lightbulbs as one of the less flickery ones in the test. IKEA art.nr 303.887.64. So much for the price to guide you.
Agreed. Most car manufacturers' LEDs flicker (just look at any slow-motion video, such as those on Top Gear or The Grand Tour), but GM's are at a much lower frequency that is visible if the vehicle is in motion, or you are in motion.
Some people are talking about using LiFi or high-speed IR communication for vehicle to vehicle communication. Seems like a great idea, but you can do it at a much higher frequency than what GM is doing today, so it's not distracting to humans.
You can dim LEDs by turning them on and off really fast using a process known as pulse width modulation (PWM). Ideally for something like brake lights you would use a constant current driver to control the light level to prevent flickering. I don't know why GM is using PWM, but I'm guessing they just use a cheap control circuit. I really hate their LED tail lights. Just moving your eyes from side to side is enough to easily see the flashing.
Also, due to leakage for large LEDs they are more efficient at higher current. That means that for a given power, you're better off driving them at a higher current for a shorter duration. You can increase the effective luminance without violating the power spec.
Cheap brands generally use some form of capacitive dropper scheme. These result in the 120/100Hz flickering but is cheap to produce as very little components are needed (X2 class capacitor, maybe some current limiting resistor(s) and a discharge resistor, bridge rectifier, or even skip the rectifier altogether). They are not to be used with a dimmer. Some info on them [1]
The switch-mode power supplies in proper lamps get the stuff done way better and there will be no noticeable flicker. Maybe in the order of several kHz in ripple which you cannot see.
Also; cheap off brands (looking at you china) sometimes have caps rated at 250V which is far from the peak mains rate of about 320V (in 220/230V countries).
I have electric heating and in the winter there is no energy benefit at all from LED bulbs. I want my incandescents back. They really feel comfortable in a way I can't explain.
They really do. I placed an incandescent on a floor lamp to use it for reading, and it's now the most pleasant light on my house by far. But it gives me anxiety to leave it on for a long period of time because I know it's a huge waste of energy. The second best are my Phillips SceneSwitches, which I really love but don't come in 100w.
I just went and tried to find a bright (1000-1500 lumens) Philips LED bulb with a cool temperature (3500-4500)... but it seems every Philips LED bulb is "warm white"* :/ That's fine for a living room, but not what I want in my home office, kitchen or bathroom.
Perhaps dimmable LED bulbs would be better in that regard? The LED dimmers on the market use a very high rate PWM (afaik) to prevent/minimize flickering at low brightness. I would guess that the dimmable bulbs are designed to work well with intermittent power and so wouldn't have the same problem.
Of course it's still hit or miss, compatibility between bulbs and dimmers seems to be very hard to judge without testing these days.
Dimmable LEDs are not automatically flicker-free. My father had very cheap dimmable ones, and I complained at every visit about the strobe effect until he bought flicker-free ones.
Most dimmers work via pulse width modulation [1], i.e. the power supply is switched on/off in a different interval (more off time means lower brightness). A true flicker-free dimmed LED has to be dimmed in an analog way (probably only feasible for "dumb" light bulbs). PWM of 20kHz or something might also work, but who knows what that does to brain waves.
I can't find the source right now, but I read that the fastest cells in the visual pathway can respond at a bit under 500Hz. Part of the reason the ieee suggests a minimum PWM frequency of 3000Hz is, for signal processing reasons I don't fully understand, that's the highest frequency the brain could likely detect, given 500Hz "sampling hardware."
In my experience, dimmable bulbs are no better. Most of them still suffer from the 120 Hz strobing effect. That's because even though they might PWM at 1-10 kHz to control the dimming function, when A/C voltage crosses zero, the "on" state of the PWM can still be a lot dimmer than the "on" state during the A/C voltage peak.
I would think a good LED would need something like a full wave rectifier with a good smoothing circuit to minimize flicker. I bet a lot of the bulbs on the market cheap out on the electronics though.
I tried this with my office lamps and saw the flickering so I bought the Philips bulbs you linked to. They just arrived and I filmed them but they also show the flickering when filmed on an iPhone in slow-mo mode.
Do I need to buy a specific model of Philips bulbs? Or is my Ikea lamp the culprit now? I paid a ton of money for a certified flicker free monitor so I'm very keen on making sure the lamps are flicker free as well.
I noticed the same thing when I was playing the guitar. The constant flickering combined with a vibrating string at a high frequency produces a nice looking effect [1], which can be observed with a naked eye (unlike the one in the video).
Interesting, I used to be very bothered by computer CRT monitors set at 60hz refresh and bright backgrounds. I'd go into the Windows control panel (most often) and increase it as far as it would go at the given resolution.
Through trial and error I found that 72hz was acceptable/ok and 90hz and above was great. Other folks generally didn't notice, but sometimes could if I showed them to look sideways etc. This must explain why I've never knowingly been bothered by 120hz LED flicker, it is below my ability to consciously notice.
Curious, I took a look at several bulbs, with the mobile at 240fps trick described elsewhere. A new Feit dimmable, new Ecosmart non, a several year old Ikea, and a no-name CFL. All showed flicker except the CFL. All the LEDs flickered, but the amplitude was larger on the ecosmart. Feit and Ikea had a small amplitude.
Perhaps they are putting half the LEDs out of phase to get the smaller amplitude, or they should?
Have you tried this with incandescent bulbs?
They flicker at 120Hz too... since they are P=I^2R and driven directly from 60Hz lines. I don't know the amplitude variation that bothers you, but then I don't mind LED bulbs.
Of course it's not the LEDs that do this but the cheap AC-DC conversion bridge rectifier.
Yeah, but because incandescent bulb filament's retains enough heat to continue to glow between peaks, their flickering is almost negligible - especially compared to poorly designed LED and CF bulbs.
Philips has some solid products. Our old television used to be Philips and it lasted a full decade and a half - we only got rid of it to get an LED TV. Most of our light bulbs have been Philips all my life and they have generally lasted a good while better than other brands we have used.
Yeah I can immediately tell when an area is illuminated by LED lights when I spot the strobing/flickering as I move my eyes and the saccade reveals the slow frequency of the light dispersal (or however it would be worded). It's super jarring and can be a bit disorienting.
On an iPhone - at least the 6S I have - you don’t even need to record a video. Just switching to slow motion in the camera app will instantly show you flicker in the live preview, I assume because it’s interpolating frames from the 120hz input.
You say "don't have this problem", but given sufficiently unstable mains input, the Philips bulbs too will do this.
Source: I just had a problem with a malfunctioning light switch (not even a dimming switch, a plain two-state switch) wherein sometimes it would poorly complete the circuit, and one bulb out of the four on the circuit would start oscillating on and off. (If you removed the one bulb, another would start. If you plugged the first bulb back in, in the original slot or another, it would happen to the first bulb only.)
I was in a hotel room a while ago which had some seriously flickering LED lights, just everywhere; moving around you could definitely see it. Wasn't pleasant.
I bought some LED string lights for my bedroom because they were cheap. They turned out to be incredibly annoying due to the 60Hz flickering. Staring at them, it wasn't noticeable but the moment you moved your head or moved something quickly you could see the strobe effect. I trashed them and bought some incandescent lights.
My Philips Hue bulbs visibly flicker when they are dimmed, but not when they are at full brightness. I never had that problem with the old style bulbs. I wonder if that could be fixed with a firmware update?
Yes, I also have the flickering issue with some LEDs, and I can confirm that (to my eye) the philips LEDs I bought do not flicker. I also have a few OSRAM LEDs that don't flicker.
I've taken every single LED bulb that has failed on me to pieces and it's always the same failure mode. The heatsink compound isn't applied properly to the back of the LED board. The LEDs immediately in the gaps smoke out.
Alas this isn't a problem. If a lightbulb goes, Amazon send me a new one out now free of charge and tell me to throw the old one in the trash.
This is one manufacturer, prevalent on Amazon, the Long Life Lamp Company. Long Life my ass.
They have been replaced by Philips and Ikea LED bulbs now which the oldest are 5 years old now and still going strong.
Edit: one thing to note is the really cheap ones run pretty hot. They have 105 oC rated capacitors in them. If you look at the derating curves at the running temperature they are clearly designed to last just past a year.
I replaced around 25 bulbs in my house with cheap Walmart "Great Value" LEDs just under 3 years ago and they've all been fine. Previously, I had replaced around 4 bulbs with Cree LEDs from Home Depot, and half of those were dead within a few months.
The Walmart bulbs without any special pricing were way cheaper than the Cree bulbs from Home Depot, but even better, there was some sort of automatic rebate or something like that in cooperation with the local electric company that made the Walmart bulbs $0.17. By "automatic rebate", I mean that the bulbs rang up on checkout at $0.17. No rebate forms to send in or anything like that.
"Previously, I had replaced around 4 bulbs with Cree LEDs from Home Depot, and half of those were dead within a few months."
Were those the original Cree bulbs with the heavy, finned metal heatsink around the base ?
I currently have a bag of about 14 of those that I bought (with great enthusiasm) and that burned out (or turned weird purple colors) within 2-3 years.
New style cree bulbs appear to have these issues solved. In fact, I continue to buy them as they perform better than other (satco, fein) bulbs that I have. In most cases I get satco/fein as long as they have the color temperature and output I want, but if I am having issues with a dimmer, etc., I get a cree bulb.
Those early Home Depot Cree bulbs were definitely defective. We bought a ton of them and have since replaced nearly all under warranty... twice. The first round they replaced with identical ones, which also quickly failed. (Always the same; started with an intermittent flicker, which progressively got more severe and regular.) More recently we've gotten a new design back, which seem better. Fortunately, after the first ones, it's been as simple as replying to the email thread and telling them how many more replacements I need!
The Cree bulbs have been a disappointment for me as well. There was so much buzz about then when they came out, but I've had so many where one of the elements fizzles out and kills the whole bulb because they are wired in series and the elements fail closed or very high resistance.
If I cared more I might try to take the bulbs apart in a way that I could get them back together and just bypass the failed LED with a resister to bring the bulb back to life (at 15% reduced capacity or so).
I have been very disappointed in how hot the bulbs run as well. It feels like they must be wasting a lot of energy to run that hot.
That's funny I had 3 LEDs die in a week and they were all great value. I believe I bought them 4-5 years ago. I've also had a cree die. Overall though waaaay better than incandecent or even compact CFL.
I bought about 100 regular incandescents in various wattages at Lowes before they were banned. I wish I had bought a lot more. They were about $0.25 per bulb at the clearance sale prices. CFLs and LEDs are poor substitutes from a quality-of-light standpoint. Also AFAIK there is no hazardous waste in a burned-out incandescent. You can throw it away with a clear conscience.
Can you not still buy halogens? I like the light they give out and while they are nowhere near the efficiency of an LED bulb, they last pretty long by incandescent standards and they are somewhat more efficient than the old argon bulbs.
The guy in the other comment apparently paid led .17$ and they are all still good after 3 years..
What is the percentage of survival of the incandescent light and how much electricity are you wasting until they die?
Similarly, I replaced all my bulbs around 2011/2012 after buying a new place and I have yet to have a single one fail on me.
These were fairly expensive, about $11 each (the going rate at the time), and were TCP brand, but it was unpleasant to read that newer bulbs might be far worse when it comes time to replace them, even if they are cheaper. I love the fact that they die so infrequently that I don't have to keep any spares around.
I have had good but not perfect luck with the TCP bulbs. I've had two or three die (out of perhaps 40 or so). They also have mediocre color compared to a newer design.
Nobody is going to deliberately sabotage their LED bulbs because nobody really has a monopoly on them. They probably use cheap components that are only rated for the warranty period, but that isn't "planned obsolescence".
Nobody is going to sabotage them, but they’re also not going to spend money making them list one minute longer than they really have to. If you’re focused on the short term or think reputation isn’t a big driver of your sales, then your product really doesn’t have to last very long.
I think it gets worse as time goes on, because manufacturers gain experience with the lifespan of their components and learn exactly where they can cut. If you’re not quite sure how long something will last, you’ll probably err on the side of caution and engineer it to last longer than needed in case you got it wrong.
A competing manufacturer can always offer a product that last longer and warranty it, and people might choose to purchase it depending on the price.
However, as the article notes, people may not be interested in paying a premium for a product that lasts 10y instead of 5y or 20y instead of 10y, since the tech can change or maybe it’s susceptical to other kinds of degradation.
For bulbs that are really cheap, people won't keep their receipts and warranty information. I think it will be hard for bulbs to differentiate by warranty.
If you buy at Costco, you can return them at any time in the future without a receipt. The return desk will lookup past purchases using your membership card.
I can't even trust that the company will be around in 5 or 10 years. Or that they won't come back with some BS why they won't honor the warranty, and how it's my fault the bulb is bad. Long warranties are basically worthless anymore.
That is true. It is not directly "planned obsolescence". But our whole economic capitalist system is based on the idea of consumption. That means that products by default do not need to last.
My flat has some sort of bad-quality switches and when switching on/off the lights I often used to have some failures when using classic light bulbs (I have no clue about electricity - in any case in some way when I press the on/off-button the transition seems to be "dirty").
4 months ago I bought a new lamp and decided to give OSRAM-bulbs a go (it's a well known brand in Europe but up until then I always used Philips) => 2 LED-bulbs failed within 2 weeks (I put in the 1st bulb => failed after 2 weeks => replaced it with a 2nd bulb => failed again after 2 weeks).
I then went back to using Philips-bulbs and the one I used to replace the last one which failed is still working now.
Philips seems to be, at least in my case, definitely better or at least more "lenient/tolerant" at least concerning my the switches installed in my flat.
Anybody having negative experiences with Philips or positive ones with OSRAM or the opposite?
It is a problem in the sense that it creates waste and pollution. There is a cost to throwing things out, and for shipping things across the country without limit.
two usage cases, one obvious to me but one wasn't.
the first being, areas with vibration meaning near doors and garage door openers. great locations to eat LED bulbs. this might be related to your heat sink adhesive issue.
the second is the upside down tulip light fixtures common in bathrooms, apparently they cook quite well unless ventilated at the top.
My friend's bathroom light that is now a strobe light and the landlord has yet to replace because it requires an electrician to replace the whole fixture would like a word with you.
>requires an electrician to replace the whole fixture would like a word with you.
Kind of like how replacing a gas dryer "requires" a licensed plumber to make the gas connection or you're "required" to drive no faster than the speed limit at all times.
You're getting the runaround. If it was in a vacant apartment that they were showing to people it would already be fixed. If they cared about getting it done ASAP they'd either shell out the big bucks or ignore the law.
Edit: I think a lot of people on HN don't realize how simple swapping failed parts is. Swapping a failed water heater or electrical fixture (especially light fixtures) is a waste of the skilled tradesman's time and the customer's money. Even an incompetent landlord or maintenance service should be able to get it done.
I have experience in this (US Midwest)
Most licensing regulation for these things are for professional commerce, and the more general the more they about demonstrating financial means to cover liability and/or a means of taxation, education or demonstration of work is of minimal to no importance. Aquiring general contractor licenses I often found myself using a web 2 fax service to submit pdf documents to a fax number... over T38/VoIP to the building department who could print the fax from their email as they required physical copies to be filed.
It's rarely criminal for homeowners to DIY within building code regulations, permits be damned. When the bank owns part, appraisal or home sales happen, insurance policies are involved non disclosure can be fraud.
My 2¢ on DIY from general contracting experience,
Water:
Undetected water leaks can be fucking expensive, consider location and worst case scenario when making decisions. Don't use shit like AS SEEN ON TV toilet tank gaskets or tool free water valves in a production environment.
Gas:
Thread seal tape is a lubricant that helps seat solid metal (usually) connections to create a seal, not a sealant. (can be welding agent for polymers)
Water, dish soap, spray bottle helps test connections.
Gases have different smells or lack there of, different densities (sink, rise, displace oxygen), can combust in different concentration ranges, etc so understand this.
Electric:
Changing the load or adding potential for increased load on a circuit (new fixtures, receptacles, breaker, fuse, conductor, etc) could cause arcing and lead to fire in unexpected ways. Sections of copper wire get replaced with smaller gauge at some point over a properties history and then get sealed back up in a wall, among all kinds of other wacky shit. Understand the physics and dangers.
Connections are important, and common points of failure. They should be appropriately terminated and enclosed. Use the proper size wire nuts.
All:
Valves, switches, and people are flaky so plan accordingly. Test shut-off or failsafe mechanisms and have a plan for the worst case scenario.
The law once mandated that you hire the services of a licensed electrician to replace a lightbulb. Imagine if the same laws where applied to tech. Need to update Microsoft office? No way arround it you need to hire the services of a licensed IT professional! You might get electrocuted in the process not being a professional. So it all makes sense.
It's not really possible to burn down your apartment building if you fail at updating Microsoft Office, so that's one big difference for gas/electrical laws.
Actually it is the law at every trade show I've ever exhibited at, just about to the point where you can't plug in anything without a union electrician doing it. One can usually get away with plugging in a laptop, but certainly if you need anything more than the single standard 10A 2-outlet power drop, expect to pay and wait for the official electrician (and they will kick you out of the show for violations).
Edit: I've seen this at least in NY, Florida, California
Generally, a landlord wants someone licensed with insurance to handle something like that on the off chance something goes wrong. I was going to fix the fixture in my bathroom that was shorting a bit and burning out bulbs myself. Thankfully I called my owner and he had an electrician come in because it turns out a lot of the conduit above the fixture needed replacing due to age.
Judgement proof typically means you have no money/assets to come after, so even if someone wins a judgement against you they aren't getting paid. That's why you ensure you hire a handyman with liability insurance, so that there's something (the insurance payout) to collect in the event of a problem. Do you mean something else by judgement proof?
> As long as you're just replacing the fixture and not running new line a handy man type person can do it legally.
That likely depends on local codes; not sure about light fixtures specifically, but I definitely have encountered variations in different cities in the same county when it comes to ceiling fans.
Few plumbers or electricians with a license are going to waste their time replacing your dryer or light fixture. They probably will send their (unlicensed) employee who's paid a couple bucks over minimum wage to do it. Their time is better spent on jobs that actually require their expertise. You know, the kind of jobs where you'd pay extra for a credentialed expert anyway. They probably will never set eyes on whatever you called them for.
Those laws (especially when combined with licensing requirements that exclude all but those who have a full time career in that field) are a massive hindrance to individuals and many businesses. They usually amount to little more than a potential transfer of liability. If your house burns down maybe you can try to point the finger at the licensed professional (good luck at that). The only thing it accomplishes is making it (slightly) harder for people who are habitually grossly negligent to keep working in that field. This is a non-benefit IMO because so much business is based on reputation anyway. The downside is that by artificially raising the minimum price access to access skilled labor you cause all sorts of work to be forgone because people can't afford it.
Plenty of house fires have been started by people who couldn't afford to pay an electrician but could afford an extension cord.
Edit: Since I'm apparently so wrong does anyone want to explain why. A down-vote without a reply is roughly synonymous with "your opinion is inconvenient to me but I cannot refute it"
...is using the downvote correctly. Downvoting is for comments that are not productive contributions to the kind of discussion desired on HN, responding to any post that merits a downvote is increasing the noise-to-signal ratio.
Why do you even need a landlord or maintenance service to swap a light fixture? Replacing a fixture is a bit more work than replacing a bulb, but it's not exactly hard.
There's a wide range of quality ceiling light fixtures that you just clip into place, and the LED chips are on a huge metal heatsink so they run very cool https://panasonic.jp/light/led/products.html
I used to think that, and I changed my mind. The fancy retrofit fixtures are almost universally flood lights where the diffuser is close enough to the ceiling plane that it’s visible from far off axis. The result is that the lights on the far side of the room cause unpleasant glare.
With a retrofit lamp, you can use a high quality trim baffle (these things cost about $12, are quite well designed, and are probably already in your house and put a civilized PAR30 or PAR38 LED in, and you get a much better light distribution.
Back when lamps were all standardized incandescents, fixtures could focus on quality. Now, with LEDs, I suspect that manufacturers focus on how cheaply they can build a driver and assembly that meets some minimum performance criteria. So, with retrofit lamps, at least the fixture design is separate.
(There are exceptions, of course. Very high quality dedicated fixtures exist, but they’re quite expensive.)
I was surprised at the early failures of my Sylvania bulbs. Had expected that going with a brand that has been in the light bulb industry for a long time, I would get decent quality, but they've all died in under a year. Now IKEA bulbs are my go-to, the mix of selection, quality and price is impressive compared to what I've seen but I haven't thoroughly researched this. Do Philips or GE do better?
I have only my anecdotal experience, but I'm happy with the Philips & GE bulbs. As I said, they both seem to run pretty cool. Philips makes what seem to be inexpensive-but-quality bulbs, as well as dimmable LED's that red-shift like incandescent used to. They also make a 60W yellow bulb that has very low blue emissions, uncommon for LED bulbs. Some of GE's LED bulbs have really high CRI which I like for making the basement more cheery.
One thing to pay close attention to on the package is whether the bulb can be run in an enclosed fixture. The package should always specify. Following this guidance and picking the right bulb for the fixture will help ensure you get the service life you expect. I don't think I've found any 100W equivalents that are OK'd for fully enclosed application, and 60W equivalent is like 50/50.
The last I looked at them, Ikea bulbs ran hot the packaging advised not to be used in small/enclosed fixtures because they could overheat. Do you find that to be the case with the ones you're using?
I have a couple of 2W/80lm ikea bulbs for bedside lighting, and they are room temperature.
I also own some 5W/400lm ikea bulbs for general room lighting and they do run warm, maybe something like 40°C ± 5°C. The fixture/thingy around the bulb is roughly the size of a fist.
The bulbs are pretty new so I can't say anything about the lifespan of the bulbs, but the price is reasonable, they are not the fancy smart bulbs.
I bought one of these for my basement hallway when I was finishing it out. My only concern is that a normal fixture has few failure modes; just the bulb. But if this fixture fails, I have to find a new one that will fit in the same spot. Hopefully it will last til I'm dead.
I've started doing this. Bought a large panel fixture and a separate high-quality LED current source and it has been absolutely great. Next time I build a house I'll probably run all the lighting circuits on a hefty 24VDC main power supply with small DC/DC regulators on every fixture. There's no reason nowadays why lighting circuits should be 120 or 240VAC.
Like I said in a previous comment, with LEDs, power requirements are small and distances within a house are small. Coupled with a resonably high but safe voltage (like 24 or 36VDC), there's no reason why 14 gauge copper wire couldn't work just fine for a lighting circuit.
I wish there was more selection available of that kind of thing— when I last looked a year or so ago there was basically just one option at Home Depot, and it had the aesthetics of something you'd put in the laundry room.
Worse than that, though, it was unusable with a dimmer switch; the whole thing visibly flickered every few seconds. I felt bad returning it because I really wanted it to work out, but the quality just wasn't there.
I have an LED fixture that I got from home depot that is dimmable, no flickering. It's connected to a normal dimmer switch. I bought it about a year ago.
My other LED fixtures were ordered through aliexpress. The fixtures were fine, but the transformers that came with the fixtures all failed and had to be replaced (overheated, melted the plastic casing). This turned out to be tricky, because the LED drivers available on ebay and aliexpress are never the same, there are constantly new shoddy ones from noname brands, and the ones I had bought before tend to be nowhere to be found when I need a new one.
I didn't know that the fixtures themselves had dimming features. I put "dimmable" LEDs in my can lights in the basement, and I'm really unimpressed with them. They don't flicker[1], but they don't get very dim, either.
[1] Except after a power outage - then they eerily flash on and off like something out of Stranger Things.
That is the constant frustration of this economic model. Either you buy the driver (or the LED bulbs for that matter) from a shop in your own regulated economic area (like the EEA) and have them handle quality assurance (including the selection of the product) and warrantee, or you get the same product directly from China for a fifth of the price and have to handle the occasional failure yourself.
The sad thing is that the latter is still cheaper than buying from a 'local' shop.
I have had good success with, and have been happy with the quality of _MeanWell_ LED drivers and power supplies. You can get them through Mouser, Newark, Digikey etc.
This is in contradiction with the article, which says that the driver is the cause in 90% of cases.
EDIT: This was not entirely correct as the article says:
> The US Department of Energy (DoE)’s solid-state lighting program supports research and development of LED technologies, and their website contains volumes of data on LED lighting systems. Their Lifetime and Reliability Fact Sheet contains data on the failure rate of 5,400 outdoor lamps over 34 million hours of operation. Interestingly, the LEDs themselves account for only 10% of the failures; driver circuitry, on the other hand, was responsible almost 60% of the time. The remainder of failures were due to housing problems, which may not be as applicable for bulbs in indoor use.
It never answers the question. It has an anecdote about the author's own lamps that ran an estimated 15-20k hours with an advertised lifespan of 30k and have degraded to the point where they will replace them. That's n=1 and nowhere near 100k hours, or even 50k as the author mentions early-adopters will remember seeing advertised.
The article contains a lot of info, but does not actually answer the original questions it poses in the title and the second paragraph.
Closest I saw to an answer was the last sentence of the "Color Shift Happens But is Unpredictable" section.
>It’s possible that the reduced lifetime ratings we see on current bulbs simply reflect better knowledge about actual performance of existing LED technology over time.
It's implied in the conclusion that 100,000 hours are not necessary because the progress of technology results in more efficient, brighter, and higher CRI bulbs.
Is it in this case. I presume that at one time there were actual bulbs which said 100,000 hours on the physical box. What specifically happened here? Do we have the same bulbs today and the marketing was wrong, or are bulbs today de-engineered?
I'm not positive on this one, but out seemed the article alluded to the idea that the 100,000hr life was measuring to LED failure and ignoring the possibility of driver failure, whereas now there are stricter standards both for measuring the potential of a driver to fail and measuring the lifetime of an LED as the point at which out drops by 30% rather than the point of total failure.
So, engineering lead of a (outdoor) led Luminaire manufacturer here. And our sales director used to work for one of the biggest Asian light bulb OEMs. Happy to answer specific technical questions out there that this article triggered.
Since the article never answered the question, do you know what happened to the 100k hours LED bulbs? Were the initial estimates just over-optimistic? Was it all marketing hype?
I can only guess that the marketing department wanted to put the biggest numbers forward against what was plausible calculations for the early LED lifetimes.
I know for a fact that some of the testing houses have done extended on/off cycle testing for some of the big box retailers looking to keep the lamp vendors honest on real lifetime performance of A19 class bulbs. I've been in such a test chamber.
My guess is that is has to do with IKEA's improving smart home trend [0]. I like the fact that the work with all three major platforms so I don't necessarily have to be all in on one if I decide to switch in a couple of years: "Trådfri [has] compatibility across Apple HomeKit, Alexa, and Google Assistant".
Seconded that. I switched to Ikea lamps back in the CFL days and today use their LED bulbs and lamps with no problems at all. Of course they're not manufactured by Ikea, but whichever is the maker it seems a very reliable one.
More of a non-technical question, do you see demand for outdoor lights at the red end of the spectrum?
Supposedly that's better for night vision, light pollution and various animals. But everywhere I go I see yellowish sodium vapor lights replaced with white LEDs.
I think it's a shame sodium vapor lamps are being replaced. Low pressure sodium (LPS) is actually highly efficient, provide a very soothing color for nighttime, and for me most importantly are easily filtered by astronomical observations (their spectrum is nearly a single line). Their size and unwieldiness is justified in utility street lightning setting.
We've certainly been asked about amber LEDs for coastal environment projects, so I think there is some demand. Amber LED performance, on the other hand, is a different story.
The lumens out of a legacy high pressure sodium lamp are very high. It is still an engineering challenge to get comparable lumens out of LEDs at price point the market will bear.
Is there a way for me to know whether or not an LED bulb will have a proper driver that does not throw away half the current and produce a "strobe" before I buy it? The flickering (in the presence of moving things) drives me crazy.
As above, look for architectural bulbs that are deep dimming rated (< 10% dimming). They cost more. I personally have had good luck with Cree, but probably the other top shelf vendors have similarly good products.
From the perspective of efficiency, defined as maximum perceived (by human eye) luminosity per watt used, what's the best color for LED bulbs? Is white as good as it gets, or is there any advantage with pure green LEDs?
The green LEDs are not necessarily the most efficient in terms of amount of light emitted per watt of energy used, if I understand correctly. Hence the question - is the increased sensitivity to green enough to overcome that inefficiency, compared to white?
Why do so many of the bulbs run hot? Like so hot you can't hold them in your hand if they were on when you unscrewed them. Isn't this a lot of wasted energy?
Partly because they are running tiny cheap power supplies pushed near their limit, and also because many of the actual LEDs they use aren't nearly as efficient as they could be. Also available surface area, in order to fit in most standard bulb locations they need to be small leaving little room for adequately sized heat fins.
yes theres multiple kinds of inefficiencies concerning the external circuitry etc, but there is also the intrinsic inefficiency of current LEDs: some of the high energy photon are downcoverted to a low energy photons by phosphors, so there is non-radiative (heat) generation in the phosphor itself. In theory it is perfectly possible to use "quantum cutting" i.e. 1 photon -> 2 photons instead of 1 photon -> heat + photon. There is quite a lot of research on quantum cutting phosphors, both for LED's and for VUV excitation etc, so these higher efficiencies will probably come, but I don't know how far out in the future. If someone knows of commercially available quantum cutting phosphors (or products using them) I would be very happy to know about them for some physics experiments...
I think they might have began quoting the LED lifetime on boxes, which is still true, but in reality something else in the bulb usually breaks before the LEDs themselves. I guess manufacturers have either taken it upon themselves or have been forced to reduce the quoted lifetime since the famous 100,000 hours marketing.
Or they quote the lifetime figure for a single LED, but then wire up a dozen or more in series to make the light. Any one of them fails and the whole assembly goes dark.
#1 more die. More die means less current per die, which helps efficacy in a nonlinear way (google "LED droop")
#2 better passives. Aluminum polymer caps, for instance
#3 lower temps, in however you want to achieve that aim
#4 some TVSS element if there wasn't one already
1) Better cooling: non-tooth paste thermal compound, more space for heatsinks
2) Not overdriven LEDs
3) Introduce DC power lines (within the house/building) - galvanic corrosion still might be an issue
4) In lack of point 3 - more efficient AC -> DC converters, preferably with lower temp threshold,
having 150C default for the internal mosfet on 8pin LED driver is really high.
4a) AC-DCs require quality passive components: coil and caps.
There's a myriad reasons why flicker and buzz occur, because there are a number of ways to achieve dimming. But all of this comes down to cost.
If dimming is important to you, there are a number of architectural grade bulbs that offer deep dimming to 5% or 1%.
Personally, for this application, I've had good luck with Cree bulbs of this type at home (on Leviton dimmers). And in the house of worship environment with Cree bulbs on Doug Fleenor dimmers (http://www.dfd.com/dmx8dim.html)
Second that Doug Fleenor recommendation. They make some fantastic lighting kit.
I'd also like to add that looking for lamps with the CEC Title 20 & Title 24 certifications should be helpful in finding bulbs that dim well, as California has much stricter regulations on dimming flicker and buzz than the rest of the country.
For LEDs, LM-80 data is used to extrapolate lifetime data via the TM-21-11 methodology. Its not great, but it is what we have. If you read the standard, it has pretty good summary of the drawbacks of the current approach to lifetime extrapolation:
Any bulb with switch mode hardware to control the LED drive current will exhibit RF emissions.
The cheaper bulb in the original article has linear current control. Inside the ASIC, this could be as simple as a BJT or FET in saturation with a (somewhat) controlled base/gate voltage, maybe with some temperature compensation.
The linearly regulated bulb will have less RF emissions, though you could theoretically still have a bit of rf trash from edge effects depending on the rectifier and filter cap.
Any bulb that has passed FCC Class B will have an upper bound on conducted and radiated emissions, but you can pass such tests on a wide range of margins, and therefore certification isn't useful to clarify which bulbs have the lowest emissions.
The trick is that you have passive cooling (a heatsink) in what could be a completely enclosed space (like a glass shade/globe on a flush-mount fixture). The heatsink can't be too big to occupy a similar volume to a 'normal' A19 bulb, or it won't be able to fit in lots of existing fixtures. I suppose we might see some bulbs try active cooling (with a fan on that heatsink), but people are already very aware of hums and buzzes from their fixtures, so it'd have to a quiet one.
I cannot speak knowledgeably to this for A19 type products, but generally there is no need to have such low temperatures to achieve good lifetimes. There may be temperature requirements this low for bulbs mounted in certain locations, but that is not a part of UL 1598 that I have in my brain.
Can't speak to any of that. The appearance to me as a consumer walking around with an engineering eye, is that the early days of expensive higher end, store exclusive home LED bulbs (e.g. Cree at Home Depot) has given away to an all out price war.
None. Our industrial customers require minimum 5 year warranty at 12hrs on per day, 365 days per year. We work hard to make both the lighting producing and mechanical aspect of the luminaires last.
I also have been disappointed with LED "bulbs". They get too damn hot in recessed fixtures but NOT because of the LED's. It's all because of the shitty power converter embedded deep inside the bulb getting too hot and failing. The industry has necessarily had to retrofit to where incandescent bulbs are supposed to go.
I think that we'll start to see improvements in this area as people move away from "screw-in bulb" as the form factor and towards using external power converters delivering power to to LED fixtures that are just LED's and their heatsink + mounts.
As an amateur radio operator, LEDs have been the absolute bane of my (and thousands of other city-based hams') receiver. Those same modules not only produce ungodly amounts of heat, but also loads of radio-frequency interference that has been contributing to the increase of the global HF noise floor over the last decade.
I think jandrese is referring to the fact that even a DC current through a plasma generates loads of RF, for example fluorescent tubes emit THz radiation!
Every so often, I come back to the "I should have DC power on demand in my house!" until I'm reminded that DC power loss over a distance can hurt bad, even 48VDC telecom power.
Perhaps USB-C PD might help? USB power adapters are compact and PD offers standard, useful high power DC. If the adapters become ubiquitous, you could see "USB-C lightbulbs".
Slight tangent but "in-building DC" exists, and is rapidly gaining popularity but not via the medium many assumed: Power Over Ethernet.
You can buy PoE LED light fixtures now, which are both powered and controlled over ethernet. You buy a single PoE switch, run some low voltage Cat6, and you can power an entire floor's worth of lighting.
EEPoE (Energy Efficient PoE) offers more efficient PoE too which claims up to 94% efficiency.
Definitely a space to watch. Particularly as the cost savings of running low voltage Ethernet cable compared to high voltage electrical cable (110v) are substantial.
Microsemi's exclusive EEPoE technology cuts the power losses on Ethernet cables by 50%, through the utilization of all the copper available on cable when a Microsemi EEPoE PSE IC or Midspan is used. It is 100% compatible with IEEE802.3at, and the savings work with ANY IEEE 802.3at Type 2, Type 1 or IEEE 802.3af compliant PD. In practice, devices that consume 25.5W would consume less than 27.75W, instead of the worst case 30W when a non-EEPoE PSE is employed.
So they use all 8 wires for power instead of just 4 to halve the power loss on the wire. For the worst case device that makes the 20% loss be a 10% loss.
Definitely watching. I once was in the LED industry when it was still hot. The company was called Zega.
They tried every random thing, including putting a small real ARM server on the bloody thing to do remote control. It was back then when I first stumbled on Espressif people and Teo. They got lightyears ahead of us with all-in-one SoC.
? Must be either very low current lighting or that's some pretty beefy Cat6. I think the average Cat6 cable is only 24 gauge and that won't carry a lot of current very far.
PoE+ will deliver 30W to the far end of up to 100M network cabling. Given that those cables radiate out to endpoint devices from a central point, rather than powering multiple devices in a ring/loop topology, the potential to power lots of devices over a wide area is huge.
Biggest problem tends to be accommodating the central power delivery device. Those big PoE switches run hot and loud.
He's talking about running a separate cable for each and every bulb. It's a wasteful solution compared to running all of the lights off of a single circuit (or limited number of circuits) like a normal building.
Certainly at the household scale this is true. I cringe at the inefficiency of rooftop solar panels, hooked up to inverters, powering transformers that supply phones, lights, and electronics. AC in the house is great for an electric oven, vacuum cleaner, or fridge compressor, but so many modern electronic devices would be happy to run off of 5V or 12V.
Look on the bright side- in terms of real power, the electric oven, vacuum cleaner, AC compressor, and fridge compressor totally swamp the entire load, waste and all, of those 5V devices.
In a perfect world we'd have both AC & DC, and could use whichever was most appropriate. We could feed DC straight from the solar panels to the cell phone. But in terms of what consumes most of the power, in the typical home it's AC loads.
In a perfect world your fridge and vacuum would use BLDC motors and be happy with whatever dc or ac voltage you give them. As my washing machine already does.
>Look on the bright side- in terms of real power, the electric oven, vacuum cleaner, AC compressor, and fridge compressor totally swamp the entire load, waste and all, of those 5V devices.
This isn't an appropriate comparison. Those appliances actually do useful things that need to get done so the energy isn't just wasted like it is with power supply inefficiency.
Sure a 12vdc circuit would be nice. It wouldn't be nice enough or efficient enough to be worth paying for.
The point is the power delivery system we have does a good job for 99% of real power consumed (or whatever the number really is).
I hate waste; my mains-connected smoke detectors (1% efficient) and garage door opener (15W standby) gnaw at my soul. But that's scope for improvement, not an efficiency crisis.
A smoke detector doesn't need that much power, so efficiency of the power supply is less of a concern. You have to find a useful compromise between efficiency and use of materials. Those additional components for higher efficiency need to be produced which uses resources and energy.
Although 15W standby for a garage opener seems excessive.
Those aren’t a waste, they are critical life safety equipment. If their 1% efficient power supply lasts the full 10 year lifespan of a smoke detector rather than 6-18 months like a typical LED lightbulb, I’d say that’s the appropriate level of reliability.
Yeah, they're important & valuable. However, battery-powered smoke detectors do it with 1% of the power.
If every home in Australia had two smoke alarms, that means 5,600 kW of continuous and largely wasted energy consumption. I don't mean wasted in purpose: smoke alarms are essential. The wasteful part is the fact that 99% of the power going into smoke alarms goes to converting AC power to DC power.
As far as I'm concerned, that's 99% scope for improvement.
That is an incredible amount of energy and I agree that it is worth trying to reduce, but I’m skeptical of adding numerous DC-DC converters to the chain. In the current state, it’s all passive devices between the turbine at the power plant and the smoke detector on the ceiling. I wouldn’t trade that reliability for power savings lightly.
Grid-scale transformers are very efficient. The tiny pole-mounted ones used in the US and some other countries probably not so much, but everything north of 50-100 kVA gets into 99+ % efficiency.
Just because generator/machine set transformers and 380/220 kV step transformers require semi-active cooling doesn't mean they're inefficient... just means that they handle a huge amount of power (MWs), so even at very high efficiencies that translates to a lot of heat in absolute terms.
The goal in my thinking was to eliminate a complex or costly power supply at the point of consumption. Higher voltages require a beefier step down (isolation, caps, whatever) and AC requires a rectifier. I wanted to eliminate it all.
Sorry, I was being a little too loose for HN. Also, I'm not an EE but I play one on the Internet :).
Power loss (I^2R loss) over distance is not caused by DC; it's caused by the combination of low voltage and high current. If current usage and distance are both small (as they would be in an LED-lighted house), wiring a house for DC is a perfectly reasonable thing to do.
Also to note that your 1KW appliances need 83 amps in a 12V DC system. This is a huge amount of current and requires special cabling (which has a not insignificant voltage drop due to the resistance of the wire) and special connectors.
Yes Please for DC power. Especially if it can remove all the power adapters. I think I have more adapters than wall sockets in my house now. Phones, Tablets, electric toothbrushes, shaver, router & switch, wifi access point, rasp pi, cameras, Laptop, Monitor, streaming device, reading light, electric piano, toy train. good grief
Isn't that a function of voltage and not modulation? There might be a cost argument, I'm not sure if solid state step-down DC-DC converters are cheaper than good old cheap transformers.
>A shock from a DC supply will cause heart fibrillations at lower voltage than AC, because of the way muscles receive signals from nerves
That is opposite to my understanding. The extra shock hazard of AC vs DC was an argument used against AC power distribution back in the day. The 50V limit is to prevent shock altogether.
As a counterpoint, I've fitted 6 LED lightbulbs in recessed fittings more than five years ago, they're used maybe 10 hours a day and they're all still going strong. It depends on the model, I suppose.
> I think that we'll start to see improvements in this area as people move away from "screw-in bulb" as the form factor and towards using external power converters delivering power to to LED fixtures that are just LED's and their heatsink + mounts.
These already exist. Nearly every architectural grade fixture has a separate 24VDC driver, the LEDs, and a heatsink. Here's a cutsheet for a Lithonia recessed can as an example:
These run for $175-200 a piece. They list 70% lumen maintenance at 50,000 hours. That's 20 years at 12 hours a day for 220 days a year. Some architectural cans are a bit cheaper, some are a bit more.
I'm surprised that there is no mention in the article of "filament led" bulbs (and very little mention in the comments): https://www.greenbuildingadvisor.com/article/led-filament-bu.... They are based on the simple idea of stacking enough small LED's that they can run on mains voltage. You still need a rectifier to go from AC to DC, and a capacitor for smoothing, but no voltage conversion means there are fewer parts to fail. And multiple smaller LED's makes the heat dissipation much easier, so they tend to run cool.
I've been using them for a couple years, and think they are so much better than the previous generations of CFL's and heat sink LED's that would quickly fail, especially in enclosed fixtures. I'm buying cheap ones from Amazon, and occasionally I get early failures, but lifespan after initial burn in has been excellent. Like others, I often wonder why they haven't taken over the market: http://www.eevblog.com/forum/chat/why-haven_t-filament-led-b...
There’s no reason they can’t smooth out the power like other lamps (except space). The linked article mention manufacturers already doing this in 2014, surely you’ll find flicker-free versions. These are all over home improvement shops over here.
My father in law is a general contractor and religiously keeps all his LED bulb receipts. If anything goes out before the listed hours he returns it to HomeDepot. He hasn’t had any issue so far including some of the older bulbs described in the article.
Worth noting that in the UK the "statute of limitations" for getting a refund on a defective product is 6 years according to the Consumer Rights Act (what used to be the "Sale of Goods Act").
AIUI in EU we get default 2 years of warranty on all goods. And we get a 14 day cooling off period on goods that are the result of solicited sales (cold [phone-]calling, selling at your door), or are bought online.
If an LED bulb should last 10 years then up to the 6 year point you should be able to get 40% back on a failed unit. Up to 2 years, get a replacement, repair, or full refund (at the sellers choice).
With the CRA the right is against the /seller/ and not the manufacturer though.
I’ve found that Cree is very responsive for warranty replacement. I usually just email them with a picture of the dead bulb and approximate date of purchase and a new bulb shows up in my mailbox a week or so later.
Pro tip: Home Depot recently started to allow receipts to be pulled up and items to be returned with just a credit card. Ikea does this too if you always scan your Family Card.
Sure, but not for any other purpose, and that's what GP means.
It's like GPS tracking: I track every trip I make with OsmAnd's tracking feature automatically when it starts routing. But I wouldn't trust Google Maps to do the same with their location history feature. Their usage of the data isn't limited to what's in my best interest, so I'll collect it myself.
if you don't pay cash, you are also being tracked (credit cards)... and soon/now you will also need a mask/burka to avoid being tracked (facial recognition).
Because most POS systems now use a thermal printer system that for some reason - even when kept at a "proper temperature" - the receipt fades over time, to where it is virtually illegible.
The conspiracy part of me thinks this was done on purpose to reduce returns and warranty claims...
This works. I did the same when I switched all our lighting to LED, and was able to replace two faulty lamps that stopped working way earlier than specified for free.
This makes me wonder if we shouldn't have an AC and DC circuits in the house. I mean, it could be all AC coming in, but at the box it splits into (at least) two different circuits (an AC one and a DC one).
AC circuit would still be used for things that have motors, but everything else uses DC.
Imagine how simple LED lighting could be on a DC circuit. Just an LED and resistor.
I only took a few electrical engineering classes so correct me if this is a bad idea.
Having an AC to DC converter at the mains to your house would be great. Using a reasonably safe 48V DC in the home seems reasonable. Modern high efficiency motor driven appliances all use internal AC->DC converters and a 3-phase DC->AC driver anyway. I'm still on the fence about what the DC voltage should be - upwards of 60-80 are still nice and require less current for a given load but you don't want your PC and TV to need too many stages to get low voltage.
It would be nice if some people got together and wrote a standard for DC powered homes. Preferably without a bunch of patented stuff included in the standard. Then all the pieces could be produced by various industry players and we could switch.
I have a big 48 port PoE switch (Ubiquity) and power tons of devices from it. You can get a GbE PoE “uninjector” which will give you a 5V micro USB output and use that to power tons of things all over the house, while also leaving the GbE usable at full speed (on Amazon). I also buy PoE versions of things whenever possible. I even have PoE switches powered by the core switch and home automation gear powered by PoE (e.g. Control4). Great low wattage DC distribution, and getting greater with PoE++ (I have just one 4 port PoE++ for now, but it is also 10GbE.)
A current limiting resistor isn't ideal for LEDs bright enough for home lighting. It's not very efficient compared to a proper constant-current LED driver. Losing the terrible power supplies in most LED lamps wouldn't be a bad thing, though.
The breadth of products like this [1] tells me you're far from the first person to think of that problem. Distributed circuits for DC is already a reality. Now we just need more light USB LED lighting solutions for around the home.
Right, but my question is would it be better to do the conversion once for the entire house or to make every single device bundle in its own transformer and rectifier as we are currently doing?
I was not clear. The point I was trying to make was that transformers are not perfect in the conversion even when there is no load there is some power loss in the form of heat. Not sure if it is a real problem or not.
You need the transformer to step down the voltage For example: going from 120V AC (in US) down to something the rectifier can use to produce the DC line voltage like 5V. An AC to DC converter will have both a transformer and rectifier.
For one, you don't need a transformer for stepping down voltage, as you can see in essentially every piece of consumer electronics nowadays. Your typical CPU nowadays runs in the 1-2 volt range, but PC and laptop power supplies and batteries provide various voltages between 3.3 and 20 V. Your typical desktop mainboard takes most of its power to feed the CPU from the power supply's 12 V rail. Yet, you won't find a single power transformer outside the power supply--the only transformers you will find on a mainboard are probably Ethernet signal transformers.
All of that is done by switching regulators, and those work perfectly fine for regulating 120 V down to 5 V as well.
Then, rectifiers really don't have a problem rectifying 120 V. Some of the cheapest diodes you can find are perfectly capable of rectifying 120 V mains voltage. In fact that works so well that almost every power supply, at least for consumer electronics, nowadays does just that: The input is fed through a rectifier and a filtering capacitor to first to procude (in the case of 120 V input) ~ 170 V DC. After that comes some sort of oscillator that then generates more or less AC from that, but at a much higher frequency, in order to feed that through a transformer--primarily for isolation, but if you have to have a transformer anyway, you might as well use it for reducing the voltage as well. The output from the transformer then is rectified again for most applications, which is a lot more difficult to do efficiently due to the high frequency and the low voltage.
I have 48vdc on my phone line which is thin wire and plenty enough power (amps) for very bright lights. This 48vdc phone line has been in my house for twice as long as I've been alive.
It seems like an efficient house would at least want a "lighting circuit" where you have a single transformer/rectifier/controller driving a bunch of LEDs all throughout your house. That type of lighting scheme seems like it could last decades if you use quality LEDs.
The usefulness seems questionable. LEDs have to be driven with current, so either you would have to have all LEDs in your house in series, with short-circuit switches for light switches, or you still have most of the electronics in every lamp/bulb anyway (saving only the rectifier and maybe needing only a smaller input filtering cap). The former is highly impractical (complete rewiring, one broken lamp makes all lamps in the house go dark, massive peak voltages if you have many lamps, ...), the latter isn't worth it either in device costs nor in efficiency gains (a shottky full-bridge rectifier probably eats less than half a percent of the lamp's power consumption at ~ 100 V supply voltage, less at higher voltages).
As others have mentioned, it seems all backwards that each bulb is converting AC/DC internally, and does not appear to have much in the way of heat dissipation for the converter or the LED chip(s).
I've built a lot of LED lighting setups, and even with the most efficient chips and converters, extremely underdriven, the footprint required to run efficiently and dissipate heat in a way that will let them last 10-20 years is an order of magnitude larger than what would fit in a bulb.
I've thought about the idea of wiring my entire house with DC for the lighting parts, for exactly this reason. But the fact that I'd have to sell my house one day stops me.
I've built a custom LED-lighting setup in my living room. There is one 10cm × 4cm × 30cm AC/DC transformer (with its jet-intake-like 4cm fan replaced with a quiet 8cm fan intended for gaming rigs) that supplies 12V from a central location, passing through a panel of MOSFETs driven by a PCA9685 controlled by a Raspberry Pi, onwards to the custom armatures in the ceiling. I can set it to all the colours of the rainbow (RGBWW LEDs), but the warm-white LEDs mean I can mix anything from a very low-key ambient amber evening lighting to a brighter and colder light useful for doing things that require, well, light.
I've only done this in the living room as an experiment, and have no intention of doing this anywhere else exactly because of the maintenance overhead and the breaking with convention.
> But the fact that I'd have to sell my house one day stops me.
“Here. It works now. Here is a manual that describes how it works, here is a box of spare parts. You are welcome to rip it all out and replace it with conventional gear. There is no warrantee on this thing, even though it's awesome.”
My experience has been totally positive, although limited to an early release of the full color Philips Hue bulbs which are like $50/each.
The Hue app kinda sucks but those bulbs have been going strong for 4-5 years. No failures of course, and one bulb that was left outside (covered) in NYC and always on for almost two years. No issues at all, and runs very cool.
Economically it’s a disaster but technically Hue lights are a wonder. Every bulb is a Hue @ my house. I can make it a 80’s Miami nightclub or make the rooms feel bigger with bright light. It’s nice.
From the article -- "The new $5 BR30 LED bulbs I just installed in the kitchen are amazingly bright and crisp: tests with a lux meter show the illuminance is more than 60% higher. Plus, they’ll more than pay for themselves in electricity savings compared to the old, inefficient LED bulbs they replaced."
This is what amazes me, I've been an early adopter of LED bulbs (Google even gave out a bunch at one time to employees) and have seen my share of failures, from color shift, to brightness degradation, to controller failure. That said, they nearly always cost less to operate than the previous incandescent lamps they replaced.
When the LED 'tubes' which replace fluorescent bulbs became cost effective I replaced all the bulbs in my garage. And when a credible can light with acceptable dimming came out I replaced all of the recessed lighting in the family room and living room. I now don't have a single incandescent lamp in the house and it has reduced by monthly energy by anywhere from 35 to 55 KWhr per month. That represents about a $50 a year in energy cost savings. The cost has come down to the point where the bulbs pay for themselves well within their lifetime range (my experience over a population of 62 different bulbs has been 7.5 years MTTF).
That said, I haven't been as diligent in figuring out exactly why a bulb has died, if it is just the power supply I expect they could be resurrected less expensively than a new bulb, caveat the reassembly of the light diffuser bulb.
This is pretty annoying as I replaced every bulb in my house with LED under the assumption that they would last at least a decade. I didn't even think to check a powered-on time rating.
Not that using incandescent bulbs is a good option anymore anyway.
At 10c/kWh, you only need about 700-1000 hours to pay back a $5 80W-equivalent LED bulb, so financially speaking something lasting only 7500 hours isn't that big a deal. It's more important in terms of house design, for instance there are a lot of fittings with inbuilt, unchangeable bulbs which are being used, if they last 20 years that might be justifiable, but if they last 2-5 years it's going to be an enormous hassle.
I did this as well and was very disappointed/frustrated when bulbs started dying only a year later. Usually they would start flickering more and more frequently until it was really annoying to be in a room with flickering light and I would remove it.
GE even had a warranty so I shipped them back on principle (shipping was nearly the cost of the bulbs themselves) and GE never responded with replacement bulbs. What a crock.
Phillips is pretty good on warranty. They either give me a cash back or replacement bulbs. I didn't even keep the receipt so they just ask for a picture of the bulb id information.
Let me guess: you've switched from yellow light to white light?
White lights emit more blue light than yellow lights, which can negatively affect your sleep. It's the real-world equivalent of uninstalling redshift/f.lux on your device.
I've invested in "smart" LEDs and I change their color based on the position of the sun. If the sun is up, the light is white. If the sun is down, the light is dimmed orange.
As I understand it, even though LED output is yellow, the primary light range emitted is blue. No idea if this study [1] is good, but the abstract explains it a bit.
I once worked for an offshoot of Sunfor - a chemical company making LED phosphors.
The first driverless, flicker free LEDs on the market were their invention. Basic idea is that if you fine tune phosphor components, and their ratios, you can make a direct 120hz AC driven LED with close to no visible flicker for as long as your output colour temperature is in between 5500 to 6000 Kelvins
> as long as your output colour temperature is in between 5500 to 6000 Kelvins
color temperature is really important. I despise 3300K+ headlights and bulbs.
Philips has a dimmable LED bulb where the temperature varies between 2200K and 2700K. I've also found standard 2200K bulbs. But mostly I prefer using single-color red orange and yellow bulbs.
My understanding is that white LEDs are basically blue/ultraviolet LEDs with phosphors to knock down the energy level of the photons. Do you have any links about the phosphor components used for different color outputs?
I was an early adopter thinking it would save a bunch of money in the long run. I went all Cree and happened to have a few Philips. The Philips are still standing tall, one burned out of the two after like 7 years. However there's these eco incandescent lights I installed in my parent's bathroom that are connected to a standard fixture powered trough one of the Lutron Maestro dimmer switches. Those bulbs have never failed possibly going on 8 years+. I'm pretty convinced that their fade in fade out dimming when you turn on/off the switch makes a graceful ramp of current that the filament never gets shocked to suffer rapid thermal expansion that eventually fails the bulb.
Cree has a good 10 year warranty though, I've sent in boxes of dead bulbs to them. However many substitutes are dying out too and they're included in many of the replacements that are going back for my next batch.
I have some electronics with LED displays/indicators that have been on 24/7 for over 30 years, or 256k hours, and haven't failed. The difference between those and the ones in bulb replacements is that the latter are driven much harder, to the point that they dissipate a lot of heat. Indicator/display LEDs don't get hot or even noticeably above ambient.
Thus it seems that, just like with incandescent bulbs, LEDs will last practically forever if they're run dimly. The difference is that LEDs are actually more efficient at lower current densities, where they're converting more of their input power to light instead of heat, but cost considerations has lead to typical bulbs driving them at much higher currents for more brightness but correspondingly less life and efficiency. They're still far more efficient than incandescents, so I guess that's what counts...
I toured a house looking to buy, 20 years ago. The old lady owner said "The light bulb over the door is going with me! I've had it 20 years and counting." It was a weird antique-looking thing with lots of wires and stuff in the clear glass bulb. Dim as hell. But 20 years! They don't make them like they used to.
The expected life of incandescent bulbs follows power laws with pretty big exponents: w.r.t. intensity its to the third power, w.r.t. voltage to the sixteenth power. So if you e.g. put a 230 V bulb on 110 V power, it will be dim as hell, but boi will it last!
So what this is saying is that light bulb companies engineered their bulbs to need regular replacement and we could have had much much longer lifespans with somewhat dimmer bulbs?
"A light bulb at a fire station in Livermore, California, has been on almost continuously since 1901. In 2015 it was recognized by Guinness World Records as the world’s longest-burning bulb.... Giles Slade, in his book “Made to Break,” traces the term “planned obsolescence” to a 1932 pamphlet, circulated in New York, titled 'Ending the Depression through Planned Obsolescence'.... the lamps market will bring in an estimated thirty-eight billion dollars this year, L.E.D.-bulb makers are already reacting to the spectre of declining sales."
Why are they putting electrolytic capacitors in these light bulbs? The SM2082D datasheet specifically calls for an electrolytic cap, but wouldn't a power ceramic cap last longer? 4.7uF is doable with ceramics. Is it just a really minor cost thing, and hoping the bulb fails so you have to buy a new one?
That's a bleed resistor to discharge the capacitor when turning off, else it could keep dangerous charge for a long time.
ESR limits current inrush into the capacitor, with ceramic caps you would need some additional current limiting.
Voltage should not be that much of a problem, but there may be other issues with ceramic caps (like cracking due to thermal stress, voltage dependent capacity, microphoning, ...)
You have to take into account the voltage that the capacitor runs at. 4u7 200V X7R MLCC is going to be huge and certainly several orders of magnitude more expensive than Al electrolytic.
I was recently excited to find an ”award winning” Ikea Riggad LED lamp on the ”take for free” shelf by the recycling area of my building.
Plugged it in, did not work. Tried dismantling it with the help of these photos — https://www.youtube.com/watch?v=jhfZ-vwau8c — but some screw sockets seemed damaged and the screws would not come off. I could not see anything wrong with cables or soldering as far as I got, so I wonder if the LED or circuit board is the problem.
Good design needs to consider sustainability, longevity and ease-of-maintenance in addition to how something works and looks.
It says more that customers overwhelmingly prefer cheap products.
A 1962 washing machine was 184.95 [1] ($1523.97 today) and a 1959 model was $209.95 [2] ($1729.97 today); which are both more expensive than all but the highest end front loader currently at Best Buy. The vast majority of top loaders are in the $500-700 range, top loaders $800-1000. There simply isn't much market for $2000 machines that will last decades.
It's a similar story for almost all home appliances I've looked at.
> The vast majority of top loaders are in the $500-700 range, top loaders $800-1000. There simply isn't much market for $2000 machines that will last decades.
Those "high end" washing machines will also fail in the same time range that the low end ones will.
There is a market for them, but it will remain unfulfilled because the manufacturers make more money in the short term with the low-reliability ones.
Just recalculate the price of the built-to-last appliance from 1980 into 2018 dollars. For the same amount, you'll buy a very decently made device today, too.
By the same token, all the large CFL and LED lamps in my house are expensive high-CRI lamps. I've seen two CFLs go due to a failure in internal electronics, likely as a result of a power glitch. The longest-running CFL I had to date ran for 7 years, for 12+ hours a day.
> For the same amount, you'll buy a very decently made device today, too.
For most products I find this to simply not be the case anymore. What I find is the more you pay, the more "gizmos" and "features" you get that ultimately lead to earlier device failures than the cheap models.
And the same may be said about the products we make today 40 years from now. Survivorship bias is the logical error of concentrating on the things that made it past some selection process and overlooking those that did not.
It's no problem to get 50,000 hour LED bulb but you going to pay $10+ for each one. Mainly due to the metal heat sink. American companies are still machining blocks of metal. The Chinese adapted other heat sink technologies to make thinner heat sink fins, when combined do the same with less materials. I'm pretty sure the next leap will come from LCD scale LEDs combined into bigger arrays which require even less for cooling since they can be printed onto various materials.
I have another issue with LEDs, I am designing an indoor device that use solar panel for recharge, and if I put my current solar panel (IXYS panel) under a LED vs under an halogen light, which are both similar in light intensity "to the eyes", I have like 100 times less energy on my panel under the LED.
I just discovered that a few days ago because I was using a LED maglight to test my panel and realized I had incredibly small power output with it. Now I am building a small circuit to measure and datalog the power output of different solar panels under different type of artificial lights (vs having to use the multimeter + oscilloscope which is not very portal outside my labs).
If you designed solar powered device for indoor use and have heard of this issue, I'm very interested.
Article does not so much as mention Philips which are the gold standard here. The off brands he’s looking at are the problem. Cree is a fine brand for LED components but not for the entire bulb assembly in my experience.
> Plus, they’ll more than pay for themselves in electricity savings compared to the old, inefficient LED bulbs they replaced.
Sure, eventually, but without further context this obsession with light bulbs always sounds a little bit penny wise and pound foolish to me.
The relative cost of lighting on the monthly electricity bill is tiny so those savings are pretty small. Getting a more efficient fridge, washing machine, TV or (in our profession) computer typically has a much bigger effect on electricity expenses. And that is assuming your heating and cooking is done with gas.
> The relative cost of lighting on the monthly electricity bill is tiny so those savings are pretty small. Getting a more efficient fridge, washing machine, TV or (in our profession) computer typically has a much bigger effect on electricity expenses. And that is assuming your heating and cooking is done with gas.
The switch from using tiny space heaters for light to using LEDs that consume a tenth of the power was a huge savings. It only takes a few 100w bulbs to equal or exceed the energy consumption of a modest desktop computer.
I don't know about you, but I had long switched to CFL's before LED bulbs came around. CFLs are definitely not as efficient as LEDs, but at least they're still a fraction of the power that incandescent bulbs use.
Modern fluorescent lamps are surprisingly efficient and the electric ballasts seem to be more reliable than any LED bulb I've seen so far. The tubes do fade eventually, but the tube itself only costs 1-2 Euros and the environmental impact is pretty low of these where the mercury cycle is closed.
>"we asked to more than 1,000 people at the end of 2009. Then, 68% surveyed threw their last energy saving light bulb in the bin." (Which? [0]) //
Bit out of date but indicative of the UK situation I imagine.
The best I could do for the USA situation was that [1] shows about 1.5M recycled CFLs in 2010, vs [2] shows about 300M sold in 2009, 0.5% recycle rate ...
The problem here is that no one knows where to recycle them. There's only a few locations in the US that recycle them and they don't accept consumer drop offs. Local recycling centers and waste centers generally don't accept them separately and just tell you to put them in the main trash. I had 15 years of bulbs stashed in a box in the garage because I didn't want to dump mercury in the landfill even though they told me that was perfectly fine, which I knew was wrong. Eventually an acquaintance told me that they had seen small tube collection boxes near the customer service desk at Home Depot. This is not advertised and is not known to the recycling centers. So the experts just tell people to landfill them when asked. If people knew where to take them it would be more than 0.5% doing it. It wouldn't be 100%, but maybe 50%.
They never became decent. They were always loaded with toxic mercury that became a hazard if the glass broke, and they had short life and though some good one existed, the market was overrun with bulbs with long warm up times, bad color, and buzzing.
Yeah, I switched a few bulbs to CFLs 10 years ago when they "became decent", and then switched them out every 6 months (i.e. when they burned out) until LEDs "became decent"... Haven't had as much trouble with LEDs as CFLs, but I'm definitely not paying $10+/bulb like I did with CFLs.
those $10 CFLs burned out almost as quickly as I could replace them. Kinda spoiled me on the whole "spend more for something that will last longer" theory.
They were decent 20 years ago. In my experience, the quality dropped sharply around 10 years ago or so. I've seen at least one CFL fail within a few weeks of buying it.
LPT: Don't buy the globe ones that go over your bathroom mirror. They are practically pre-burned-out for your convenience.
CFLs are everywhere, but came with a lot of downsides. My personal observation was that they were never more than 50% of the bulbs in a house (that I ever saw).
Even a moderate desktop with no dedicated graphics would idle at around 30 Watts. I tried taking this further a couple years ago with an i5 and a 200w PSU that was targeting low loads and got to 18w idle.
They're basically at the same level if you don't use high end CPUs and gaming GPUs. Also see here: http://www.extremetech.com/extreme/135719-5-9-watts-the-worl... - tldr: 30w idle for an unmodified average system.
Mind you this was 2012, mid range systems surely haven't gotten more power hungry since then.
That's an order of magnitude more than an idle laptop.
And they're not talking about any sort of "average system" they're ballparking a "reference desktop" which tops out at 150W under load, that's not just "don't use a gaming GPU" that's "don't use a GPU at all". And if you're building a "desktop computer" with an APU and an SSD… why are you building a desktop computer?
I have to admit that I have used only CFLs for decades (with a few exceptions where the produced heat was a positive side-effect, not a negative) and had not considered there are plenty of households that still use incandescent light bulbs.
> Sure, eventually, but without further context this obsession with light bulbs always sounds a little bit penny wise and pound foolish to me.
Might be, might not be, it all depends on the usage of the various items e.g. let's say I've a 100W incandescent kitchen bulb, it's lit 5h/day on average, an equivalent LED would be 12~15W for ~$5 and will save ~3000Wh per week.
Going from a Class A to an A+++ washing machine would save ~500Wh/cycle. And I can buy 50~100 bulbs for the price of the washing machine, so that'd be both penny foolish and pound foolish.
Maybe "without further context" you should avoid hard and fast assertions, should run the numbers and should help people try and profile their energy usage instead of putting down their efforts?
> Going from a Class A to an A+++ washing machine would save ~500Wh/cycle.
The major energy cost for clothes washing is heating the water. A rooftop solar water heater dramatically reduces energy use, often more than one would get from using the same space to install solar panels.
A front loading washing machine uses less water than a top loading one and will also use less energy for water heating.
> The major energy cost for clothes washing is heating the water. A rooftop solar water heater dramatically reduces energy use, often more than one would get from using the same space to install solar panels.
Most modern washing machine are cold-water only, washing machines with a hot water inlet tend to be prosumer. Same with dishwashers.
OK, that's very interesting. It's not true in the US, never seen a cold only machine.
Wait, are you talking about the machines that have an electric heating element inside the washer? And you can still wash warm and hot cycle, but they don't require a connection to the hot water heater? Or are you talking about machines (which I've never seen but am willing to accept exist in other countries) that actually only offer cold cycle as a washing option?
If we're talking about ones with an internal heating element, those generally use about twice as much energy to operate than ones that rely on a hot water intake. But with the two input machines one has to figure out the energy to heat the water as a separate cost, which is what I was mentioning. Gas heated hot water heater will be more efficient than electric heated, and solar heated will be most efficient of all.
> Wait, are you talking about the machines that have an electric heating element inside the washer? And you can still wash warm and hot cycle, but they don't require a connection to the hot water heater? Or are you talking about machines (which I've never seen but am willing to accept exist in other countries) that actually only offer cold cycle as a washing option?
The former. I don't think I've seen a consumer-grade dual-intake washing machine in 10+ years.
OTOH Japan might actually have the second, I dimly recall my sister mentioning something along those lines.
I don’t think anyone making such policies thinks that those things alone will save the planet. It’s about a mentality into the daily choices we make that makes the difference.
That said, leds that are 13-15 watts instead of 60 watts does make a big dent into saving electricity at the country scale.
I mean, without any numbers it's difficult to know what your understanding of "much of a difference" is, but replacing 60W incandescents with 10W LEDs can save MWh/year for a single property.
A single bulb used 5h/day[0] on average means 90kWh/year. Aside from lowering the load somewhat, depending on the electricity prices the LED bulb might pay for itself in a year.
[0] which is not really difficult, 6 to 7 in the morning and 18 to 22 in the evening and you're there.
These wins are all relatively easier than weening the country off massive cattle farms, personal gasoline cars and jet fuel vacations, and they can still be environmental wins. I think the energy they take from larger problems is immaterial and so there isn’t any harm done.
Of course a person with a house the size of Gates' would think it cute. Every house in Medina, WA could switch to LEDs, and the carbon footprint of Gates' house would make the savings a rounding error for that town.
> The relative cost of lighting on the monthly electricity bill is tiny so those savings are pretty small.
Only because of the successes up to this point. Marginal gains in LED efficiency aren't going to do much, but the shift from incandescent to LED has had a big impact.
There's a simple joy in trading out some dying halogen bulbs for so much brighter LED bulbs which use the same power. It's absolutely optimizing in the wrong place, but it's super satisfying.
Given the starting "plus" of that sentence, it's obvious that the author's concern isn't so much the energy savings of the newer bulbs over the older ones, but the improved quality of light over the now aged bulbs. With that much yellowing on the older bulbs and a per-bulb price only 1/9th of what it used to be, I'd replace them too without a damn about the electricity savings -- that they would lead to any savings at all would be a bonus.
Getting a more efficient fridge, washing machine, TV
And after I've done all of that? Or maybe I'm looking for easier, less expensive wins than dropping $700 on a fridge? Let's not poo-poo the choice of replacing inefficient, CO2-producing tech by being quick with the "yeah, but...".
And why is he comparing to Incandescent anyway? He should be comparing to CFL, and against CFL LED bulbs are rather poor - more expensive, same energy efficiency, same life. Why do it?
I have LEDs in my house, but only because my local utility pays for most of them. If not for that I'd use only CFL's - they are cheaper, and just as good.
All my LED lighting had better efficiency numbers than CFLs. There's not the same saving as going from incandescent because obviously you can only make that saving once. But they're definitely better.
LEDs also don't care about cycles. A CFL doesn't like being cycled on and off very much. So that leaves a temptation to say well, I'll be back in here again in a minute and leave it switched on. No temptation to do that with LED.
My personal biggest problem with LED bulbs is that my entire (100 year old) home is wired with neutral free light wiring and a lot of 3-way switches. This makes using dimmers very hard and most do not support 3-way and many will not work with LEDs and no neutral wire. Some do - Lutron Caseta makes a nice neutral free dimmer that works on many of my bulbs - but others don’t and I then just use high efficiency incandescents. Shame. Maybe there is a good “neutral free dimmable LED” that allows reasonable leakage current so the dimmer can work.
Personally I love the heat that an incondecent bulb emits, I can actually keep my hands warm on my keyboard while lowering my room heat. 75 watt bulb with heat versus a 3000 watt space heater.
Depending on where you live, the energy “inefficiency” of a light bulb is no such thing.
In the UK, for example, during winter (and spring and autumn) the heating is appreciated! However, it is 2-3x more costly than using gas central heating. (However however something something whole house vs room-specific heating.)
In the summer, it’s a complete waste though.
Directed infrared heating panels may be the most efficient because they do what you describe - heat you up directly, rather than heat the air in the room.
It's also heating the ceiling, which will reduce the efficiency further.
It's a straightforward issue of separation of concerns, there are some occasions where you want heating and lighting always tied together, but they are niche. Almost everywhere in the world you have large periods of the day or year when you want lighting without heat.
There are far infrared heater bulbs that just emit IR and don't get too hot, so you can keep them on the desk without distracting light or getting burned while also keeping power consumption low.
One potential solution would be to standardize the driver and lighter assemblies and allow them to be independently replaced. You could even then have lamps with a single large driver which connects to many small lighter assemblies without duplicated effort. Of course, that standardiZation process could take a very long time and have a wide variety of form factors, output levels, etc... which is sort of where we are anyway with light fixtures and bulbs today!
Reading about bulbs lead me on a journey and I somehow stumbled upon limelights (aka oxyhydrogen bulbs), which was the original theater lighting 'bulbs'. Basically, you can direct a torch over a block of lime (or a cinder-block I guess) and it will become extremely bright.
As pointed out in the article the LEDs just fade away. This means that if you define "lifetime", you also need to define how much you can lose brightness to still considered it to be alive.
Could it be that with the initial 100k LEDs the definition was different than with current ones? As mentioned, the industry is now using the 70% of brightness as the limit. Since such figure was probably not defined early on, maybe the vendors put the limit much lower.
So it seems like part of this answer could be that the age statement could have changed even if the bulbs did not. After a dozen or so years on the market they have learned to promise less.
The article goes into how the color and brightness degrades naturally over time, so it may also make sense that they counting more of that behavior as failures rather than the traditional "burn out".
Although the article talks of LED wearout, I think the key data was a survey of outdoor LED systems: 10% of failures are the LED itself, the other 90% is support components that fail causing shorter lifetimes.
I'm curious how it compares to the LED filament lighting which can use much simpler power supplies with fewer components which should mean much lower failure rates.
The AC-DC or DC-DC converter will likely die long before LED's junction. Primary failure mode is capacitors "drifting" and closing the mosfet inside the buck converter too early.
This is why I tell people to buy simple "driverless" LED bulbs. A shitty constant current driver is worse than not having it at all.
Cree's 1st generation LED bulbs are one of the worst purchases that I've made. I outfitted my entire house with them, but they started dropping like flies. The failure rate was around 50% and the cost of shipping back a bulb under warranty was the same as buying a new one.
I personally haven't have a LED bulb last 2 years yet, most last 3-6 months. I get them from dollar stores, Walmart, and Ikea. Maybe there is some magical lighting store that sells good ones, but I think there are 3 burnt out ones in various places in my house as I type this.
The biggest advantage of LED over fluro for me is light quality. High quality LEDs can put out a pretty nice spectrum which for me makes them ideal to replace halogens or incandescent. I use 100W (actual) LED flood lights for my loft and I love them.
Two of my Cree bulbs failed a couple months from each other about five years into a 22-year advertised life. I realized it wasn't worth it to pay to ship them the bulbs for replacement, so I just decided not to buy more Cree bulbs.
Three years in on a bunch of very cheap Ikea GU10 LED bulbs, haven't seen any failures yet. Though one of them occasionally likes to buzz softly at random times.
The fittings are open-backed (not ceiling-recessed) which probably helps.
First generation "high power" LED (I have a bunch with E27 socket) had a small cooling fan... If you ever owned a laptop for a while, you know what happens to small fans after a (admittedly long) while.
In some of the fixtures in my house, I've thought of installing small fans running at low speed (resistor in series with the fan slows it down) to stir the air and help cool the lamp.
Bad LED bulbs, like bad headphones, or TVs that emit high pitched whine, brought to you by undiscerning people with broken senses who nevertheless insist you're crazy.
Somewhat related, I am collaborating with someone on building an indoor aquaponics system, and he's ready to pick out LED lights. We both are really confused by all the acronyms (PAR, PPF, PPFD, etc). Does anyone have a good, ELI5 (or ELINP: Explain Like I'm a Normal Person) article on what to look for?
And why does every single LED stoplight I see have large segments of unlit LEDs?
Seems like some municipalities got sold a pile of crap. At least they work even with the missing lights, but who knows how often they are having to replace those?
All the failures I've torn down over the years had failed power supplies and perfectly functional LED's. I've got a drawer full of the for little projects.
Most of mine have lasted about a year. So a few times longer than incandescent, sure, but cost a lot more. And I am sure the energy cost of manufacturing them (including mining for rare earth minerals) is so greatly more that over their lifetime they use more energy than incandescents which were made of simpler materials.
I bought some G9 bulbs, and they are not performing like the halogens... It doesn't give me the full RGB like halogens and my house looks pale white(lacks red) instead of full color.
I might go back, I do not like the look of my house, and I find myself turning on my living room lights AND dining room lights. The brightness wasn't there.
There is massive improvement to be made on LEDs still.
If you're getting a pale white, "operating room" color - look into "warm white" (instead of cool white or "sunlight") LED bulbs. I've found them to be the closest to an incandescent you can get. Be aware, though, that some "warm white" bulbs are toward the "cooler" end of the range and look more white; you'll need to try a few brands to find the color temp you like.
There's a wide variety of products on the market - not all led bulbs are the same. Google for example: led CRI
G9 is probably quite challenging for high-performance LEDs because the size is so small. In the other sockets like E27 and GU10 there are lot of options available and also products designed for commercial use (where you need certain characteristics because you want to make your products look good under the light).
Seems like a capitalistic society will never get away from products with built-in planned obsolescence. It's all about the profits. Buy and replace consumers...
There's a great documentary on planned obsolescence for those that haven't seen it.
I film all the LED bulbs I buy in slow motion at 240 fps with an Android phone, and play the movie back on a PC with mplayer using the dot(".") key to move frame by frame. Here is a shot I made comparing 2 brands of LED bulbs: https://youtu.be/QbenId_F2RQ (Edit: yeah you don't have to transfer to a PC, just playing back in slow motion on the phone will still show the effect quite well.)
It's amazing how I find this way that most (but not all!) of LED bulbs flicker with a strobe effect at 120 Hz (frames alternate between bright and dim) because they have crappy power supply designs that fail to smooth the A/C voltage. As a result they flash one time during the positive phase and one time during the negative phase of the 60 Hz A/C mains frequency.
I find this unacceptable. Although not too noticeable in normal conditions, a 120 Hz strobing light is definitely noticeable when your eyes move or track an object illuminated by the bulb.
In my experience, Philips lightbulbs are one of the few brands that don't have this flaw because they take care of converting AC to a stable DC voltage internally. In fact they are advertised as such: https://www.amazon.com/dp/B07CFRCGKC "COMFORTABLE LIGHT: Our products meet strict test criteria including flicker, strobe, glare and color rendition to ensure they meet EyeComfort requirements"