Lamps / luminaires for walk-in freezers

I have seen China-made 100W 120V lightbulbs sold in the USA to mostly have rated light output of 1100-1200 lumens among the ones that dare to state a claim of lumen output that can be believed by those who know what to expect... Along with life expectancy usually in the 1,000-1,500 hour range.

Compare to a "Big 3" 120V A19 incandescent achieving 1170-1210 lumens while having rated life expectancy of 750 hours, and longer life versions with 50% more life or double that life still achieving 1050-1100 lumens.

I would take the 25 watt decrease in power consumption available from a

75W "Big 3" lamp over a 100W Chinese one of similar light output!

Did you research power consumption and light output of that one or any other of the famous lightbulbs lasting a century?

If you can check out the light output and the power consumption, I would bet my favorite bicycle that whatever "century bulb" has light output less than 60% of that of a "big 3 brand" "prime" 750 hour or 1,000 hour or

1,500 hour one of same design wattage and same design voltage.

Keep in mind that having an incandescent lamp operate at a filament temperature on the conservative side for impressively long life expectancy usually increases electricity cost of achieving a given illumination level more than lightbulb replacement cost is decreased if the life expectancy is designed to be increased beyond both 750 hours and roughly

250-300 megajoules of energy handling by the filament at rated voltage.

The resistor that reults in a 150W 120V lightbulb receiving 120 watts...

That is roughly 103 volts delivered to the lightbulb, with roughly 17 volts across the resistor. With 1.15-1.16 amps through the resistor...

This is roughly 19-20 watts of power dissipated into the resistor, and beware that a 20 watt "sandstone style" resistor can fry a small piece of bacon at roughy 12 watts!

And what does this gain?

Power consumption reduced by about 8% or about 12 watts (from 150 to about 138 watts)

Life expectancy of a 750 hour lamp increased to maybe 5,000 hours

Light output reduced from about 2900-2980 lumens to about 1730-1800 lumens - awfully close to high endf of 120V 100W A19!

Do please consider the cost of 38 watts of extra power consumption against savings of making 750 hour lamps last maybe 4700-5,000 hours!

- Don Klipstein ( snipped-for-privacy@misty.com)

This is so ridiculous that it is hardly deserving of a response. But, since it has been cross-posted to a non-lighting group, it should be answered. I can't prove a negative, but I know how hard lamp design engineers work to optimize both life and efficacy in the face of both energy regulations and market forces that demand the lowest cost product. No responsible company would throw away product life, though they do trade life for better efficacy as is well known to those who understand incandescent lamps. Also, remember that when a lamp burns out a company has no guarantee that the consumer will buy their brand as a replacement.

This is not proof of anything other than an outlier or a misapplication. There have always been lamps that ran at lower operating temperatures than normal due to manufacturing mistakes and also lamps that were operated at lower than rated voltage due to wiring problems - which will also reduce filament temperature and greatly extend lamp life.