The Great Lightbulb Conspiracy (2014)
spectrum.ieee.org
spectrum.ieee.org
Another problem is that manufacturers overdrive components. To make bulbs cheaper they just use few more mA of current, that makes LEDs run hotter, more smoothing is needed and caps get hammered by switch mode power supplies.
Without changing light fixtures to be open, allowing circulation of air nothing really can be done for standard e27/bayonet bulbs. I have personally experienced this and had clearly seen the huge difference in LED bulb lifetime between light fixture - glass globe with hole in the bottom (no air vents at the top) and another one that was just a bowl with open top. Never had to change a bulb in second one versus 5-6 changes in globe one.
but I had some bridgelux 10W that I just threw in some copper tubes on an aluminum slug with a minor affordance for cooling (some slots cut in the Al to promote convection). These ran at 80C and lasted for >5 yr at at least 80% brightness. and still the primary failure mode was the little meanwell dc/dc converters playing thermal runaway. and that whole assembly cost $10
it just has to be penny pinching at the end of the day.
In Dubai they actually have efficient and long-lasting LED lights [1]. These exist in order to satisfy strict government regulation there. They’re not sold anywhere else because they’re more expensive to make (more LEDs per bulb running at lower output).
In 90% of cases where LED need replacement problem happens in this transformer unit. In rest 10% it's on LED fault - but it's also problem because they are series connected and when one is gone whole circuit stop. If they are parallel connected such issue won't happen.
They don't appear to be available in the US though, that's true.
I think I'll get a couple to try for those places where I think "60w incandescent equivalent" is sufficient, although cynical experience tells me to expect 40w at most - but for low single digit wattage power draw I'll accept that in some places.
Mostly I like to see though, so I'll keep buying their 150w equivalent bulbs.
- LEDs light bulbs are overdriven to show better numbers on the box
- they are designed for universal voltage range: AC 90-264V
- which leads to extra overheating in the US/Canada and passive component failure, due to high current on the primary
- in 230V range, the common failures are the LEDs, themselves (black dot of death), due to lack of decent heat dissipation (and generally overdriven)
- as a general guidance - buy the heaviest bulbs at a specific lumens, they may have Al heat sinks, better heat dissipation, better passives
Overall the LEDs cannot retrofit well in the existing sockets, e.g. E27, esp E14, for incandescent light bulb. The LEDs need to have enough room to dissipate heat and run AC/DC converter with decent passives. OTOH, near custom ceiling LEDs driven at decent currents (with no terrible drivers) would last many years - but they require some electronics background to repair.I have never thought of that, since it's not a problem on its own. But yeah, this makes the first point way worse than it by itself. It's enough to explain all the geographic difference in quality I have noticed.
> as a general guidance - buy the heaviest bulbs at a specific lumens
But this does not work very well. You can easily get a 20 times difference on the power supply waste between bulbs. If the one that is 20 times worse is 10 times heavier, it will still have a much shorter life time.
An example of a similar (LED based discussion) a year back: https://news.ycombinator.com/item?id=35371750
One thing we noticed with other brands was that not only many fail after a year or so, the ones that still work have significantly redeuced efficiency.
LED bayonet fitting bulbs in the regular light fittings in the rest of the house seem to only get a few years though.
I think it's reasonable to be skeptical about numbers. But to imply that modern LED bulbs are unreliable is IMHO absolutely ridiculous.
Good news is we can solve the problem if we ban incandescents and mandate light fixture replacement renovations.
The cartel tested their bulbs and fined manufacturers for bulbs that lasted more than 1,000 hours. A 1929 table listed the amount of Swiss francs paid that depended on the exceeding hours of lifetime.[11] Anton Philips, head of Philips, said to another cartel executive, "After the very strenuous efforts we made to emerge from a period of long life lamps, it is of the greatest importance that we do not sink back into the same mire by paying no attention to voltages and supplying lamps that will have a very prolonged life."[6]
So, yeah that looks exactly like the evil actions of a cartel unless maybe you're claiming this isn't factual. If so, I'd be very interested in your source of information.
Higher current (hot filament): 1000 lumen, 100 W, 10 lumen/watt, 1000 hour lifetime
Lower current (colder filament): 333 lumen, 50 W, 6.66 lumen/watt, 3000 hour lifetime.
To emit 1000 lumen for 3000 hours you'll use 3 of the former lightbulbs (one after another) and consume 300 kWh, 100 per lightbulb.
And you'll also use 3 of the latter lightbulbs (in parallel) but you'll spend 450 kWh, 150 per lightbulb.
[1] https://upload.wikimedia.org/wikipedia/commons/1/19/Black_bo...
Remember, an incandescent light bulb is primarily a heater -- even in the very best case, most of the energy input becomes heat.
This heater just happens to be so hot that it glows white and produces usable light.
What does that translate into in practical terms for a lightbulb manufacturer?
The cartel was more of a marketing self-regulation conspiracy so that one manufacturer can't make claims that their bulbs are more cost-efficient when they're just plain dimmer.
Dubious. Most people would not rewire a room in their house to install a new ceiling light because a new bulb was half as bright as the old, because the new bulb would probably still be adequately bright and the new light level is something they could adjust to (much easier than rewiring their ceiling.)
In other words, there isn't a linear relationship between bulb brightness and the number of bulbs people use. The number of bulbs people use is relatively unresponsive to bulb brightness because bulbs need fixtures and changing fixtures is a pain in the ass.
Imagine you sold a 2000 hr bulb that has two filaments in it, in parallel. It would fit the same fixture and make the same light as the equivalent 1000 hr bulb, but it would consume more because it runs at lower current and temperature.
You would make more money: almost all of the cost is the same as for the 1-filament version, but you could sell it for a higher price because it lasts twice as long. The buyer would pay for it slowly in the electricity bill, and ultimately be screwed.
First, I assume you mean half as bright. Half as dim seems like the opposite of what you mean, or a very strange way to phrase it.
Second, you're saying that bulb lifetime scales linearly with brightness?
Looks pretty close to it
If that matches the meaning of "evil conspiracy" isn't something that people will settle on.
We can make just the LED itself replaceable without having to swap heatsinks.
We can make it future proof with pins for RGB and color temperature.
Why aren't there any standards for modular LED lighting?
Here in Japan, ceiling lights have a standardized socket[0] so ceiling lamp fittings are easily user-replaceable without people being stuck with old bulb fittings, and so ceiling LED lamps are not fitted as bulbs but typically a large flat metal plate with the LEDs mounted to it[1], which results in fantastic cooling and good lifespan.
[0] https://www.garageland.jp/wpimg/hikkakeceiling_topimg.jpg
[1] https://kensroom.c.blog.ss-blog.jp/_images/blog/_bda/kensroo...
Edit: Our apartment was built in 1998, at the height of "CCFLs are the future", and the hallway lights are all recessed "G24q" bulbs, which I had never heard of before.
There were supposed to be the CCFL-native replacement for Edison screw bulb sockets, where instead of having to build the CCFL ballast into each bulb, it was external in the ceiling socket, increasing longevity and decreasing the cost of the bulbs themselves.
We have yet to need to replace any of them, a much longer lifespan than I've ever had from one of those CCFLs with the ballast embedded in the base of the Edison bulb. With a less-compromised ballast they also work much better (light quicker, less affected by temperature)
A set of reflector spots (replacing 45W halogen bulbs) all in recessed ceiling fixutres in one specific location within the house failed within a few months of one another.
Another spot in the kitchen, in an exposed can, failed within a year or so. It was located directly over the sink.
I suspect moisture / condensation as issues in both, as the ceiling cans have minimal insulation between them and the roof, and the kitchen fitting would be exposed to steam / vapour coming off the sink.
Other than that, a couple of stick-style closet bulbs have failed, also apparently electronics. And one fixture in the garage which seems to have been physically struck.
That's over roughly a decade's experience and roughly 30 bulbs / fixtures. Far better than incandescent or even CF bulbs. Though still not quite meeting expectations.
I think the biggest difference is that these downlights have separate driver modules and a short wire to the lamp itself, which must make the thermal aspect a lot easier to manage. This also puts the electronics up out of the condensation.
The bulb in a regular socket in the bathroom on the other hand has the driver electronics there in the bulb, being heated by the lamps, so they're getting a lot hotter, and also it's there in the steam from the shower etc.
I'd suspect that in/near the fan might reduce condensation / humidity. Lavatory moisture is no joke.
There’s only a few bulbs I’m aware of that follow this pattern. The Philips Dubai Lamp takes this to an extreme. A 60W equivalent uses only 3W. Other 60W eq. LEDs tend to be ~3x that. All that heat has to go somewhere.
I just picked up a 40W eq. bulb from IKEA that has double the normal amount of LED strands- they’re unusually long, too. It also uses about half the power of the LED bulb it replaced. I expect it to last quite a long time.
Heat is a primary killer of many electronic things, including LED bulbs and their constituent parts.
And LEDs -- the diodes themselves -- do tend to become more efficient (in terms of lumens produced per Watt of input) when not pushed to their extreme operational limits.
And it is definitely possible to create a longer-lasting, more-efficient LED bulb.
It's absolutely trivial to do this, even: To start, just add more LEDs, reduce their individual RMS current, improve heat sinking and dissipation, and use better capacitors.
But it does cost more to do these things, and regular consumer products are all built down to a price.
This isn’t some weird surprising tendency. The forward voltage (the amount of energy needed to shove each electron through the LED) increases with current, approximately according to the Shockley equation. The external quantum efficiency (photons out per electron in) is no more than 1, and tends to get lower at higher current [0]. The wavelength of the emitted photons is pretty much constant. So you get the best efficiency when the current, and hence voltage, is low.
Incandescent bulbs, in contrast, don’t have a meaningful quantum efficiency, and they produce a more useful spectrum as they get hotter.
[0] There’s a ton of detail here, for example https://www.degruyter.com/document/doi/10.1515/nanoph-2018-0...
Approachable explanations like this are a huge part of the reason I hang out here.
The RAB bulbs have a weird stair step warm-then-cool when turning on and off. They also have a huge non-linearity when dimming. That makes the Philips version more desirable, but they’re 2700k.
This may or may not be the only thing in play for that much of a difference, but my absolute favorite thing about LEDs is that their power consumption vs brightness is not 1:1, so taking an LED to 50% brightness will use <50% power. (So then doubling the number of LEDs means you will always get more brightness or less power or I suppose both if you split the difference.)
The IKEA bulb’s rated at 450 lm, 2700k, 90+ CRI. It uses 2.8W. Both are dimmable and I suspect the IKEA bulb has a higher R9 value.
I haven't bought a Cree product since then no matter how cheap Costco marks them.
They were, for sure. However, in 2019 they were sold to another company and I do not know what may have changed since. All of my Cree lights pre-date that.
> I had one of their CFLs
Cree was founded entirely on the premise of creating LED lighting, I am pretty sure they have never done CFLs.
Don't get me started on blinding LED headlights. It's so hard to see on the road at night these days.
See https://FlickerSense.org for a PhD scientists personal account, and, https://LEDStrain.org forum full of people that get migraines, dizziness, eyestrain and headaches from LED lights and other forms of flicker like temporal dithering.
Shitty light, and they consistently averaged a shorter lifespan than cheap incandescents across two houses. Nope. Done with that tech forever.
https://www.techbriefs.com/component/content/article/15641-t...