
20kW Bulb Turns Night into Day - bane
http://nerdist.com/watch-as-a-20000-watt-light-bulb-turns-night-into-day/
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x1798DE
This may be a bit OT, but I feel like it's unfortunate that "watts" (i.e.
power consumption) is the default unit used in lighting. It's like measuring
the speed of a car in miles per gallon.

Seems like it's changing a bit after CFLs came out and they started putting
luminosity outputs on the packaging, but I think people still mostly go by
"incandescent watt equivalent".

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fulafel
Power = energy flow per unit time. So you can talk about radiation output,
radiant flux as it's called in physics, in terms of watts: 683 lm of light at
555 nm wavelength equals 1 joules/second (=1 watt) in radiant flux[1]. 20 kW
in light output would be about 14 megalumens.

[1]
[http://www.dfisica.ubi.pt/~hgil/fotometria/HandBook/ch07.htm...](http://www.dfisica.ubi.pt/~hgil/fotometria/HandBook/ch07.html)

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Keyframe
You can get 12kW/18kW with ballast for cool ~$40k
[https://www.arri.com/lighting/m_series/products/arrimax_1812...](https://www.arri.com/lighting/m_series/products/arrimax_1812/)
Arri had, and Mole Richardson still has a 24kW version too. Here's an 18K
burning insects:
[https://www.youtube.com/watch?v=74ub_bysnl0](https://www.youtube.com/watch?v=74ub_bysnl0)

Passing by one (a few meters away) feels like you could (and you probably
could) grill a chicken in-front of it.

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saganus
Can someone explain to me what's going on with the control panel? I see three
round things and rotating things below that. What are those?

Also, isn't it dangerous to have that equipment indoors in a carpeted room?
Obviously he probably knows what he's doing and so I would guess it's not
_that_ dangerous because of that, but still looks scary.

Finally, how do you get that amount of power in a house? does he have a
special installation that provides more power that a regular house connection
would?

~~~
PhantomGremlin
I'll take a stab at this:

 _I see three round things and rotating things below that_

It's some variation on this variable autotransformer:
[https://en.wikipedia.org/wiki/Autotransformer#Variable_autot...](https://en.wikipedia.org/wiki/Autotransformer#Variable_autotransformers)

that's a way to gradually increase voltage.

 _isn 't it dangerous_

I was also more than vaguely disturbed by how casually he was operating. That
bulb perched on a stool didn't seem all that stable. But as you say, "he
probably knows what he's doing".

 _how do you get that amount of power in a house?_

"two hundred amp service" is very common in the USA. I just checked the
breakers in my garage. My main breaker is labelled 200 Amps. It has two
"poles". Which means there are two separate 120 Volt inputs (referenced to
Neutral). The inputs are 180 degrees out of phase, so across them is 240
Volts. 240 * 200 = 48,000 watts.

~~~
saganus
Ah. It definitely looks similar to that. I also noticed that he would move the
skull shaped lever up and down and that would change the rotation on the
transformer so I guess it's also to show the power up process.

Yes, I was also thinking about that fragile thing leaning over and causing
damage.

Aha... that explains it. I knew I was missing some math!

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jhallenworld
I wonder how much uv it is generating.

