Wikipedia:Reference desk/Archives/Science/2022 December 26

= December 26 =

Everlasting lightbulb
Is it true that it would be possible to create a lightbulb that never burned out? But that Big Lighting don't do this because it's in their financial interest for people to keep buying replacement bulbs. — Preceding unsigned comment added by 146.200.126.234 (talk) 02:59, 26 December 2022 (UTC)
 * Never? It wouldn't be possible to create anything material that would outlive the heat death of the universe. 42.189.193.127 (talk) 03:07, 26 December 2022 (UTC)


 * In a case of "they don't make 'em like that anymore", there is the Centennial Light in Livermore, CA. ←Baseball Bugs What's up, Doc? carrots→ 04:34, 26 December 2022 (UTC)
 * We could still have those if brightness inflation didn't happen. At first you could buy extremely low temperature ("warm" color) incandescents that were only a few watts and about as bright as a candle but brightness inflation happened and we get wasteful 100 watt "cool" white incandescents that are about 150 to 130 candles depending on clear or frosted. I unscrewed all but a single clear 15 to 25 watt incandescent in a cheap chandelier and put the dimmer switch way down and could still read and avoid a minefield of Legos at ridiculously low brightnesses (the light was way warmer than without dimming). An incandescent can be easily designed to last over a century if it's dim enough although max duration might need very few turn offs per century (including blackouts and uscrewings). But at least now we have rapidly cheapening 50,000 hour LED bulbs with way more and rapidly increasing light per watt than incandescents. Which is already leading to 300 watt equivalent LEDs as soon as efficiency raises the "brightest LED we can make that lasts a sane time" to that. People are never satisf
 * ied. Sagittarian Milky Way (talk) 18:03, 26 December 2022 (UTC)
 * "might need very few turn offs per century " : maybe this is the most important point. Turning on/off and cooling down/heating up places a strain on it much higher than simply emitting light. Bumptump (talk) 11:56, 29 December 2022 (UTC)
 * That bulb's fate is told in "17776" iirc. —Tamfang (talk) 18:46, 30 December 2022 (UTC)
 * I'm not sure about never, but you used to be able to buy "long-life" filament bulbs that simply had a thicker filament so they were not very bright. But there is some truth in the idea of their planned obsolescence. See Phoebus cartel. Shantavira|feed me 09:20, 26 December 2022 (UTC)
 * some good advice here: Dr Dima (talk) 00:25, 28 December 2022 (UTC)