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All Of Argentina, Uruguay Without Electricity After Massive Outage

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Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#101

Post by dep_b »

cesarb wrote: post #13
hfkajshfaks wrote: post #11

Earlier quoted context omitted.

I don't understand why BsAs temperature would drop just because the e got knocked off, or why it ceases to be an analog function after the cut :S

My guess would be that it's an average of several temperature sensors, and that a sensor going offline registers as zero. So when the sensors come back online, there's a sudden jump in the calculated average temperature.

The power drops so often that Argentina would be quite a bit warmer than officially registered here if it were true.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#102

Post by Filligree »

mulmen wrote: post #72
hfkajshfaks wrote: post #8

Earlier quoted context omitted.

It isn't really though. A cascading failure can knock out an entire grid. The Northeast blackout is an example. A line goes out. while (there some lines are still live): The current redistributes itself among neighboring lines. Neighboring lines trip end BlackStart() BlackStart() is fun. Having your plants and grid down is like having a dead battery (plants use ~30% of the electricity they gen on themselves) and no o…

Thanks for this, it is very informative and not something I had considered before. I'm curious about the statement about renewables though because it seems that with wind or solar the production is very irregular even in normal operation. Doesn't that mean there has to be some technology to balance individual generator differences which would make re-starting those installations easier? Re: Nuclear, how much energy i…

"Nuclear poisons" refers to neutron-absorbing substances produced through transmutation. When the reactor shuts down, it will continue to produce these for some time after the shutdown -- Xenon-135, particularly.

This proves problematic during reactor startup. Since it's absorbing neutrons, the controllers would need to retract the control rods further out than during steady state in order to achieve a replication rate of 1.0. However, xenon-135 stops being a nuclear poison after absorbing its neutrons... which means the replication rate will increase, and the reactor might run away.

This is part of what happened in Chernobyl, though they'd also disabled most of their safeties. (And dismantled the others.)

Regardless, nuclear poisons are something to keep a very careful eye on.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#103

Post by pjc50 »

amelius wrote: post #90
amaterasu wrote: post #31

Earlier quoted context omitted.

I'm trivialising the problem, but whichever station energises the grid first becomes the reference. An operating grid has what may as well be infinite inertia (it isn't infinite of course), so new stations coming online must match it (or try and change the phase of the grid to match theirs). I visited a power station in Melbourne many years ago, and they have the shattered remains of a turbine and generator that was…

Ok but imagine a circular grid of N nodes. Following the circle, the stations are connected to the grid. Of course there is a small, inevitable mismatch at every connection. Then, when connecting the last node, you might get a problem which can only be solved by adjusting the settings at the other nodes.

It turns out that this can be a substantial problem, resulting in wasted loop flows: https://iopscience.iop.org/article/10.1088/1367-2630/18/10/1...

Generally systems try to avoid too much loop power in the first place for this reason, setting up a directed but acyclic graph with some redundancy links carrying zero or near-zero power as standby.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#104

Post by Scoundreller »

agumonkey wrote: post #30
kabwj wrote: post #20

Earlier quoted context omitted.

>There is a common misconception that the number one driver of TV pickup is the boiling of kettles. In fact, this only creates a pull on the local network for a short period of time until the water has boiled, and can therefore be managed relatively easily, whereas flushing the toilet causes a longer surge at the water and sewerage pumping stations, and opening the refrigerator lets the chilled air escape, causing th…

dry toilets and solar concentrator kettles, yesterday

Or a wifi connected kettle or toilet that pre-heats pre-commercial or delays tank re-fill respectively.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#105

Post by sboctrl »

6thaccount2 wrote: post #64
sboctrl wrote: post #41

Earlier quoted context omitted.

The EPRI Power System Dynamics tutorial is a free resource that is really solid https://www.epri.com/#/pages/product/1016042/?lang=en-US .

Can confirm. This is one of THE best references out there for explaining a lot of key power systems topics. I didn't think it was publically available though?

It is one of the few products that is available to everyone. And frankly one of best deliverables from all EPRI programs. Period.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#106

Post by MisterTea »

ics wrote: post #48
MisterTea wrote: post #44

Earlier quoted context omitted.

Neat job. I've always wanted to poke my head into ConEd's system and see the whole thing from behind the scenes. Years back I remember ConEd was replacing two or three very large transformers down the street of a large venu I was working an event. Turns out we worked the same event the next year and amazing the same day ConEd again had the second transformer scheduled to moved into place. What an operation. Huge trai…

Heh, our most recent replacement a few weeks ago came in at almost 900,000lbs with oil. Depending on the speed of the replacement you can't always move the transformer dry because you need a certain amount of time between filling it and putting it in service.

That sounds like quite the transformer. That must have been at one of the big 345kV subs. And I assume shipping filled is to avoid the time needed to remove air bubbles.

I know a few people in the ConEd trenches, one guy is a lineman who does all the >=69kV stuff and the other guy worked in substations and was in mott haven last I spoke to him (cushy job).

I'm always amazed how much new tech con ed has installed and how much old stuff is still kicking around. I live in south queens and we're all 4kV overhead fed from area subs in turn fed by 27kV. Some of those 4kV poles have westinghouse transformers from the 30/40's still in service, glass insulators, and leftover wooden pins from older insulators. Some are so old the primaries have fallen off and just hang between two adjacent poles, some the crossarms are half falling off. Amazing this grid doesn't go down more. Then the next pole is brand new, composite strain insulators, cutouts, reclosers, metering, etc. All modern hardware. And I know some areas they upgraded the 4kV overhead to 27kV. The secondaries are in even worse condition, ancient cloth insulation half weatherd/baked off. But it all still works.

I really love how there's this massive network of cabling and systems which orchestrate the flow of power from multiple synchronized generators so it can get to your humble wall socket and charge a phone or turn a light bulb on.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#107

Post by cesarb »

kragen wrote: post #85
pdonis wrote: post #75

Earlier quoted context omitted.

5000W seems like a very low power draw for heating on the spot. Heating water requires about 4000W per degree Celsius for a flow rate of 1 liter/sec; a typical shower flow rate is maybe a third of that, so call it 1000W per degree Celsius of heating. So 5000W would only give about 5 degrees Celsius of heating, which doesn't seem like much.

While you're right that 5000 W is only 1.2 kelvin liters per second on water, typical shower flow rates are about 8 ℓ/minute, 133 mℓ/s in SI units, and at that flow rate you get about 9°C of heating. This may be a reason electric showers are more popular in tropical countries like Brazil, Perú, and Costa Rica: ΔT = 9° gets you from 28° to 37° just fine. And you always (well, usually) have the option of lowering the s…

> And you always (well, usually) have the option of lowering the shower flow rate to get a wimpier flow of much hotter water.

Don't overdo it; when I was a child, I burned a shower head by doing exactly that (lowering the flow to get hotter water).

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#108

Post by cesarb »

L_Rahman wrote: post #66
kragen wrote: post #38

Earlier quoted context omitted.

I haven't tracked the cellphone network status continuously, but here in Buenos Aires, I had a VoIP call from 8:30 to 9:00 which worked fine. Until it didn't, at about 9:00, but that's par for the course with fucking Movistar. I was using cellphone data because the power was out in the house. I didn't realize it was out in the entire country. Here in Argentina, municipal water is totally reliable (I've never heard of…

Not OP, but deeply interesting to me and especially so as I travel around South America. I am completely fascinated by the home infrastructure choices in different parts of the world. I'm currently in Sao Paulo and the hot water setup is a little scary. There's no hot water reserve or hot water plumbing at all. The only hot water source is in the shower. It's heated electrically in real time by a 5000W appliance that…

> I'm currently in Sao Paulo and the hot water setup is a little scary. There's no hot water reserve or hot water plumbing at all.

While that's a common setup, some homes have instead a "boiler" which is a large water tank heated by a electric resistance. The disadvantage is that, once you've used up all the hot water, it takes a long time to heat up again; electric shower heads are instant. Another common setup is a gas-powered heater; I never liked these, since they're dangerous (you have to be very careful to always leave the window open while they're operating, and always be mindful of leaks). Sometimes a home has more than one setup at the same time (like having the gas-powered heater for the kitchen and one service bathroom, while the main bathrooms are on a boiler or use electric shower heads).

> In homes with bad grounding

Or no grounding; I live in a relatively modern building (~30 years old) which predates the newer three-pin power plugs, and all sockets have no ground. I suppose, though I'm not certain, that the power panel for the apartment has no ground wire, with the neutral being connected to the ground only near the meter in the ground floor.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#109

Post by el_isma »

kragen wrote: post #38
Scoundreller wrote: post #15

How resilient has the cellular phone network been in this outage? How resilient is the municipal water system in an outage like this? Do most people in Argentina and Uruguay cook with (piped/tank) gas or electric ranges?

I haven't tracked the cellphone network status continuously, but here in Buenos Aires, I had a VoIP call from 8:30 to 9:00 which worked fine. Until it didn't, at about 9:00, but that's par for the course with fucking Movistar. I was using cellphone data because the power was out in the house. I didn't realize it was out in the entire country. Here in Argentina, municipal water is totally reliable (I've never heard of…

> Uruguay has much less use of natural gas, for regulatory reasons: gas appliances can only be installed indoors if the room in which they are installed has a window to the outside that cannot be closed, thus removing the risk of explosions in the case of a gas leak. Consequently in Uruguay gas stoves are almost unheard of, and nearly all cooking is electric. Many hot-water heaters in Uruguay are still the gas-powered tankless type that is nearly universal in Argentina, though. They're just installed outdoors.

Uruguayan from Montevideo here, and I disagree with this. I've seen very very few electric kitchens. Almost all the stoves I've seen are gas powered. Most use gas tanks, and some have piped gas into their homes. Hot water heaters are usually electric, and installed indoors. You'd only have a gas heater if you have piped gas.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#110

Post by [deleted] »

EGreg wrote: post #78

I really take no pleasure in saying this THE PROBLEM IS CENTRALIZATION!!!! In this case, of the electric grids. In USA there are a few huge transformers that can be knocked out with an EMP, carrington event or otherwise, and plunge the USA into a similar situation. We need to decentralize: Electric grids (solar, etc.) Cellphone towers and ISPs (mesh networks) Social software and collaboration (open source software pl…

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