Longer-lasting light bulbs: it was complicated

So... yeah. And I didn't even get into things like the effects of thermal cycling stress! Couple of fun facts that didn't make it in: one way to make an "energy-saving long-life" bulb is to design it for 130V, thus when on 120V supplies it's being underrun. And those are very weird because, for instance, it'll often be marked a "60W bulb" - but only at 130V. So in a sense it's like installing a dimmer that you can't go over 85% brightness or so. It works, but you have the same efficiency and output trade-off. And to touch on that thermal cycling stress, light bulbs for stage lighting were pretty niche and expensive, so stage lighting controllers would often have slow warm-up period upon power-up and never switch lights fully off when a show was going - instead, a very small amount of current was run through the filament to keep it hot, but not hot enough to glow. There were plenty of ways to extend the life of incandescent light bulbs, but every one had its own little unique trade-offs. Be glad we have better tech now!

"The world is complex, and you should be skeptical of simple narratives." That's a great message that is applicable far beyond the topic of planned obsolescence.

Congratulations on 2 million subscribers!

"Incandescent light bulbs are called that because they rely on the phenomenon of incandescence to produce light in a bulb." I love this explanation.

Remember those 90's batteries that you could pinch to see the color change to show how much charge was left? I'd be interested in a video explaining those.

Another important thing about the centennial light. They never turn it on and off, so it doesn't experience thermal shock like a bulb in normal use would.

"The world is complex, and you should be skeptical of simple narratives." So true. Such a simple, straightforward message and narrative. I'm not skeptical at all of it.

I wish Veritasium put a fraction of the effort into his videos that you do in yours.

You are a youtube treasure. Its very difficult to find a channel like this that places enough effort to carefully investigate a topic, displays well documented demostrations and with arecording quality that is just amazing. Thank you for your educational videos and greetings from Colombia.

One of the reasons LEDs burn out too quickly sometimes is that the electronics in their bases are heat sensitive. So installing them in a fixture that doesn't allow air circulation around the lamp, like most fixtures meant for incandescent and halogen bulbs, can make them overheat and burn out. So if you find you are changing LEDs often it might be due to the fixture not the light source.

Honestly, to me the most interesting thing here is the part about the tungsten evaporation process, as I always wondered why lightbulbs blacken over time when there's nothing in there that could form a layer of soot.

As far as planned obsolescence in LED bulbs, I have found paying like 5% more than the absolutely cheapest makes a huge difference in their longevity.

I've always wanted to see an incandescent bulb filament without the enclosure glass burn out. You've satisfied my life-long curiosity.

I was one of the people who used the Phoebus cartel story to prove planned obsolescence, so this was some humble pie for me, haha! Amazing and informative, as always. I love getting to learn something new--especially when it corrects something I'd thought before!

I just wanted to say thank you for the lack of ads. As someone who (occasionally) uploads YouTube content, I know it's possible to have it set so that ads periodically interrupt videos. This would probably make you more money, but you don't, and it is such pleasure! There's nothing like watching 20-40 mins of quality content with no interruptions. Again, my thanks!

This is consistently some of the best content created on this platform. No hyperbole. I would watch this with cult like devotion if it were on pbs, or British television, or if I had to pay a cable bill to see it. You are truly adding to the society you are a part of, while educating those who choose to watch. Thank you, and I hope you know your self worth, because it is immense!

I am so thrilled... I asked you about this topic on Patreon, you made a lengthy response concluding with "I've never really thought of making a video about this, but honestly you have me thinking about it now"... and here it is ! Thanks a lot !

As an electrical contractor this was an amazing dive into a niche area. Thank you

At my University in Germany this was actually the topic of one of my first lectures (mechanical engineering). So I want to contribute because you excluded Halogen-lamps: Halogen lamps use e.g. Fluorine to bind the sublimated tungsten and "refill" the tungsten wire at the thinnest spots. Thats why those lamps have a much higher life expectency and brightness/efficiency, though need a socket that can withstand higher temperatures. I remember vaguely that Osram had a warranty program where you could send in black-tinted halogen lamps, because it meant there was a defect in the manufacturing process, since the tungsten isnt supposed to "get" to the glass.

My coworker hit this case spot-on. Before energy efficient bulbs were a thing, he intentionally bought a 230v light bulb to install in a 120w fixture. This bulb would then run all day every day, and had clocked more than ten years of just sitting there cooking away energy to produce a modicum of light.