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A lightning bolt would be worth only about a nickel (2015)

engineering.mit.edu

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Re: A lightning bolt would be worth only about a nickel (2015)

#121

Post by themitigating »

csdvrx wrote: post #77
themitigating wrote: post #63

Earlier quoted context omitted.

The typical house has 240 volt service in the US (two legs of 120v). I would also say a decent number of homes have 200amp as well

> The typical house has 240 volt service in the US (two legs of 120v). Can we wire that in a way to would allow installing .uk or .de Schuko Type-F plugs? It would be funny (and weird!) to have 220V available on a european socket for say a desktop equipped with a 1.5kW PSU for the upcoming Nvidia 4090 :)

Maybe motors because you can replace the neutral (in eu) with a hot (us) and it's basically doing the same thing.

Re: A lightning bolt would be worth only about a nickel (2015)

#122

Post by themitigating »

yourapostasy wrote: post #117
themitigating wrote: post #63

Earlier quoted context omitted.

The typical house has 240 volt service in the US (two legs of 120v). I would also say a decent number of homes have 200amp as well

A surprising (but still tiny) number of US houses also can have three-phase brought out to them by the electric utility. Some utilities will charge you upfront for stringing it up and lighting up the wires, but another surprising number of utilities will just amortize it from the monthly cost of service. It's still rare enough you have to ask ahead of time if you want it for any building you get into, but in some maj…

3 phase gets you 108v on each hot leg. Many items will specify 110v/120v . 108v is close enough

Re: A lightning bolt would be worth only about a nickel (2015)

#123

Post by MonkeyClub »

andrewla wrote: post #106
MonkeyClub wrote: post #93

Earlier quoted context omitted.

Same here, I find the KWh to be a very useful unit for daily calculations of that sort, where I want a quick upper bound on things to make estimations. Last year I switched off my fully-functional 2008 workstation (a lovely Fujitsu Celsius W370 on OpenBSD, a furry joy) because of such an upper bound difference (300W vs 65W for the ThinkCentre that hides among the books on my desk's side). This sort of works in a simi…

> 300W vs 65W A watt to watt comparison is fine. Why hours? I can tell you right now that the big one uses ~4.5x the power. Is it really that much easier to convert the time you're using the device to seconds? If you're going to multiply by the electricity cost anyway, might as well break out the calculator one step early.

Yeah exactly, I didn't even need to take time into account, I was looking for the upper bound presuming it's always on with a simple Wattage comparison.

But that was mostly because that workstation, albeit lovely, had a very long boot process.

The ThinkCentre boots in under a minute, so I actually end up only booting it when needed.

(Some of my work can be done offline, and I jump at every opportunity to `halt -p` and be in the quiet offline space/state.)

Re: A lightning bolt would be worth only about a nickel (2015)

#124

Post by whoomp12342 »

trelane wrote: post #115
whoomp12342 wrote: post #82

if so little power, how does it fry a tree?

It's not so little power, it's so little _energy_ (power over some period of time). It's a crap-tonne of power, just over a _very_ short period of time. And yes, power is what fries the tree: https://en.wikipedia.org/wiki/Joule_heating

mind=blown. I never considered the time factor
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