This would be the funniest thing to do. 100K Amps is doable, the question is for how long. That would be one very impressive bank of capacitors. And to turn a 00 into plasma would have some spectacular side effects, such as raining molten copper across a sizeable area. Just your reading glasses would indeed not be enough, there probably isn't any PPE that I would consider entirely safe other than sufficient distance from ground zero. But now I'm really curious. I have a spot welder that will do bursts of 5KA and that will happily throw the breaker every so many welds. 100KA sustained will be a fair engineering challenge.
Ah, that lego project... that was one I always wondered if I should have industrialized it but sourcing enough lego was a real problem.
Holy crap. That's a whole series of bad ideas extremely well executed. That guy probably has never seen what a lead acid battery can do when it explodes. He keeps hiding away from the hot metal but in the path of ~half of those batteries. Ignorance is bliss.
The 'what is safer' question for DC and AC at the same effective current and power has a mixed set of answers depending on conditions. For instance, DC is more likely to cause your muscles to contact and not let go (bad), but AC is more likely to send your heart into ventricular fibrillation (sp?, also bad).
AC arcs are easier to extinguish than DC arcs, but DC will creep much easier than AC and so on.
From a personal point of view: I've worked enough with both up to about 1KV at appreciable power levels and much higher than that at reduced power. Up to 50V or so I'd rather work with DC than AC but they're not much different. Up to 400V or so above that I'd much rather have AC and above 400V the answer is 'neither' because you're in some kind of gray zone where creep is still low so you won't know something is amiss until it is too late. And above 1KV in normal settings (say, picture tubes in old small b&w tvs and higher up when they're color and larger) and it will throw you right across the room but you'll likely live because the currents are low.
HF HV... now that's a different matter and I'm very respectful of anything in that domain, and still have a burn from a Tronser trimmer more than 45 years after it happened. Note to self: keep eye on SWR meter/Spectrum analyzer and finger position while trimming large end stages.
I have a couple of those narrow escapes one of which led me to put a significant chunk of Eastern Amsterdam out of power. Another involved Beryllium oxide. 9 lives are barely enough.
Ah! Perhaps you are a member of the gigawatt club? Eligible for entry once you have accidentally tripped off 1000 MW of load or generation! No sweeping that under the table
I think the real reason is because battery power didn't have to be converted twice to be able to run the gear in case of an outage, so you'd get longer runtime in case of a power failure, and it saves a bunch of money on supplies and inverters because you effectively only need a single giant supply for all of the gear and those tend to be more efficient (and easier to keep cool) than a whole raft of smaller ones.
Yes, and that tiny little difference can cost you a lot of expensive gear if you run it off the battery and plug in a serial port or something like that. You'll also learn first hand what arc welding looks like without welding glass.
Not going to happen. For the same reason that the US never converted to a higher domestic voltage even though there are many practical advantages. The transition from one system to another at the consumer level would be terrible, even if there would be some advantage (and I'm not sure the one you list is even valid, you'd get DC-DC converters instead because your consumers typically use a lower voltage than the house distribution network powering your sockets) it would be offset by the cost of maintaining two systems side by side for decades.
You could wire your house for 12, 24 or 48V DC tomorrow and some off-grid dwellers have done just that. But since inverters have become cheap enough such installations are becoming more and more rare. The only place where you still see that is in cars, trucks and vessels.
And if you thought cooking water in a camper on an inverter is tricky wait until you start running things like washing machines and other large appliances off low voltage DC. You'll be using massive cables the cost of which will outweigh any savings.
I'm not sure it's likely, but I could see DC lighting start to happen in new construction. Have a single AC-to-DC converter off the main service entrance that powers hard-wired LED lighting fixtures in the house. Would probably be better than running the individual (and usually very low quality) converters in dozens of standard LED light bulbs. Would need to be standardized, codified, etc. so probably not happening soon.
I suppose that still begs the question somewhat, since the US does have 240V (2 phase) already driving many appliances. Why hasn’t it ever become standard for luxury kitchens to have a European-style outlet for use with a European kettle? I know the US already has a different 240V plug shape, so it might have to be an unlicensed installation, but surely someone wanted hot tea faster and did that calculus before?
Well, as you say, it would not be according to code and the insurance company might have something to say about it. It's also single phase but not quite the way you do it in the USA, it would be a neutral and a phase whereas in the USA I think it is 2x110. Finally, it's 50 Hz rather than 60 which would work fine for resistive loads but not so well for inductive ones such as transformers and motors.
In all likely not worth the trouble. When I moved to Canada I gave away most of my power tools for that reason and when I moved back I had to do that all over again.
> In all likely not worth the trouble. When I moved to Canada I gave away most of my power tools for that reason and when I moved back I had to do that all over again.
If you ever have to do it again, you can probably get a transformer rated high enough for power-tools for cheaper than replacing all of your power tools.
I wired a UK kettle to an unused 240V range outlet in the US once. It was amazing, boiled a liter of water in just under a minute. Obviously kinda sketchy.
You can run 240V circuit to kitchen for kettle and put in NEMA 6 outlet. But few people care about fast boil and importing European kettle. Most people use the microwave or stovetop, and 120V kettles are fine in most cases. It will never become a standard thing.
> I know the US already has a different 240V plug shape, so it might have to be an unlicensed installation, but surely someone wanted hot tea faster and did that calculus before?
How expensive would a proper AC->DC->AC brick for that power level be?
Not so simple, you'd have to use a 'drier' or 'welder' socket for that otherwise you won't have enough power. A single circuit in Europe is 240V 16A or 3840W!
A pure sinewave inverter for that kind of power is maybe 600 to 1000 bucks or so, then you'd still need the other side and maybe a smallish battery in the middle t stabilize the whole thing. Or you could use one of those single phase inverters they use for motors.
I just wish I could run my air conditioner and my desktop computer at the same time without flipping the breaker. The RTX 5090 is a space heater and will easily peg at the 600W it’s rated for, and so with that and an air conditioner window unit, I have to run a long cable from another unused room if I want to do anything that stresses the video card.
HVDC is a miracle of modern engineering that could not have been done in the days of Tesla. It removes several sources of losses that otherwise would have turned valuable power into heat. That said, it isn't without drawbacks: the cables are quite expensive, harder to repair and somewhat fragile, and 'local stepdown' which otherwise would just be a properly rated (capacity and insulation) transformer now turns into a much higher technology exercise. HVDC is for now relegated to a long haul role not unlike oil pipelines compared to the AC network which is far more interconnected and wide spread. You are unlikely to see HVDC used for lower level distribution in the next decade, just as you are unlikely to see your local gas station hooked up to an oil pipeline.
DC is also much harder to switch than AC; the latter has zero-crossings which tend to extinguish any arcs that form, but DC will just keep going. Look at the DC vs AC ratings on switches and you'll see a huge difference.
> the cables are quite expensive, harder to repair and somewhat fragile
Nope, HVDC uses the same style of cable as AC. I'm not sure why you'd think they'd be different.
The HVDC cables that can be expensive are meant to be submerged. A feat that only HVDC can do. HVAC can't be submerged due to the capacative effect.
But otherwise I agree. It's more a pipedream for me that HVDC becomes more common place as I believe it'd make grids ultimately more stable and resilient.
Hm, yes, you are right, I must have been reading on submerged cables, but it's a while ago.
The devil is in the details here, AC tri-phase cabling can not easily be re-purposed for HVDC purposes because you only have a pair of conductors rather than three 120 degree out of phase lines. So while technically the cable itself can be the same the carrying capacity of a triple of conductors would be reduced and one of the conductors would be idle, so if this is an in-ground or overhead cable not specifically made for DC that is a lot of wasted carrying capacity.
> With a bunch of AC microgrids joined by a DC major grid, you can completely sidestep that problem.
Not necessarily. Big local consumers will be large relative to the microgrid, which will not have a lot inertia. This is one of the things that you really notice when you go 'off grid', your grid is essentially your house and whatever else you decide to power from it and unless there are a couple of beefy motors already running starting a new one has a high likelihood of tripping the inverter, even a very beefy one. Start-up currents for larger consumers can be really high and you need a lot of inertia in your grid to overcome that.
> Start-up currents for larger consumers can be really high and you need a lot of inertia in your grid to overcome that.
This is true of an AC grid as well. Big inductive loads will often have to buy special equipment before hooking up to the grid because of their impact. It'd be the same with a DC first grid. To overcome a large startup current they'd likely need to buy a bunch of capacitors. Which, funnily, is exactly what they'd have to do to run on straight AC.
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