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What Happened to the 100000 Hour LED Bulbs?

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Re: What Happened to the 100000 Hour LED Bulbs?

#51
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.

Re: What Happened to the 100000 Hour LED Bulbs?

#52
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.

Re: What Happened to the 100000 Hour LED Bulbs?

#53
post #20
post #12

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 Lon…

Do not buy "bulbs," they are hopeless. Just buy a whole fixture with a big aluminium PCB and directly bonded chips.

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.

Re: What Happened to the 100000 Hour LED Bulbs?

#54

> 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…

> 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.

Yeah, this is worth emphasizing. Just a handful 100W bulbs running from 5PM-11PM can consume several kWh every day.

Re: What Happened to the 100000 Hour LED Bulbs?

#55
post #19

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

Given the high failure rate of drivers, do these new bulbs have higher reliability?

Much, much higher. They are the ones which will most likely be replaced due to actual LED failures, and not other components.

The problem... they got copycated within months, even though copycats did not understand the importance of a fine tuned, custom made phosphor.

Re: What Happened to the 100000 Hour LED Bulbs?

#56
post #37

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…

To convert from AC to DC you need a transformer and a rectifier and there will be energy loss during the conversion.

Re: What Happened to the 100000 Hour LED Bulbs?

#57
post #52

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 yea…

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.

Re: What Happened to the 100000 Hour LED Bulbs?

#58

> 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…

> 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…

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.

Re: What Happened to the 100000 Hour LED Bulbs?

#60
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.
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