/diy/ - Do It Yourself

>>1215930
5% voltage drop is not going to make a 1,000 hour bulb last 10,000 hours. Not even close.

https://en.wikipedia.org/wiki/Lamp_rerating
I actually have a spreadsheet template for running these calculations quickly and easily. I have some sort of autism for incandescent lighting.

In my experience, they are fairly accurate in practice, especially if you don't go into extreme adjustments.

A 5% voltage drop (down to 114V for a 120V lamp) doesn't even get you to 2000 hours. In order to break 10000 you need to reduce all the way down to 99V, and you end up with rather poor efficacy, as expected.

Doing any better than this would require a lamp of superior design than the norm to begin with. Lowering the voltage is not magic, it's a trade-off that kills your filament temperature and efficacy in exchange for lifespan.