Submitted by larsattacks94 t3_ycog36 in explainlikeimfive
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Comments
patchinthebox t1_itnkgru wrote
I work at a power plant and this is very accurate.
>Brownouts would progress rapidly to full blackouts within a day or even hours as Grid demand far outstrips the supply,
We'd be in a total blackout situation within the first 24 hours for sure. A few units would trip and the others would quickly be overwhelmed due to no actions happening and a cascading blackout would occur. Once units trip they're not coming back for a long time.
bandanagirl95 t1_itonk08 wrote
I wouldn't even bet on it surviving for 12 hours. Too much supply will destroy some units just as easily as too much demand, and the daily shift in power usage can do that either way.
calladus t1_itozs5y wrote
What if the load wasn't as bad. Say, almost everyone died?
SnooFloofs3486 t1_itp05ai wrote
The system would still fail very quickly. Components are designed to trip off line anytime the power is to far out of balance. And most at the utility level don't automatically come back online.
If you want power when the grid is down, solar and battery is the best bet.
sparrowlasso t1_itp8ohz wrote
Dying people don't turn off their appliances.
Aporkalypse_Sow t1_itp2nku wrote
The amount of stuff that's automatically set to turn on is insane enough of a power draw.
[deleted] t1_itoebps wrote
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Dingo_The_Baker t1_itnqa7p wrote
I actually work in Texas power industry and remember when that storm hit. After it was all over the CEO held a meeting and congratulated everyone for their heroic work. I work a menial desk job, so afterwards I actually pulled my boss aside and asked her what he was talking about.
The dumbed down version that she gave me is that if the grid overloads and starts to fail, the power surges through the lines and burns them up. Imagine thousands of miles of high voltage fuses burning all across the state. As it was places were without power for days or maybe a week. It they hadn't been able to manage the load, it would have been months upon months to rebuild the system.
immibis t1_ito2dfn wrote
(I do not work in the power industry but) the lines wouldn't burn up, as they have fuses for the worst-case scenario. In the worst-case scenario, power lines wouldn't burn up but they would still have to drive around and replace all the fuses.
As I understand it, the real problem in a major event is that all the safety systems trip. You get these cascading failures where the computer at each power plant and substation is like "oh fuck, something's really wrong, fuck it, I'm out" and then disconnects whatever section it's responsible for. No actual damage (that's the point of the safety systems), but everything is shut down and disconnected.
E.g. https://en.wikipedia.org/wiki/Northeast_blackout_of_2003#Sequence_of_events - according to this list, you had a few individual things disconnecting themselves and the rest of the grid took up the slack, but then within a few hours it got to a point where there wasn't any slack left and then you get this big cascade where everything that trips due to overloading causes something else to overload, and it just spirals until everything is disconnected. I assume the "heroism" at your company is related to the fact this didn't happen in Texas, so whoever still had power lines could still get power.
And then they have to figure out how to restart the whole grid from zero without tripping all the safety systems again. Did you know that most power plants need electricity to start up, which apparently makes it quite an ordeal? https://en.wikipedia.org/wiki/Black_start
> To provide a black start, some power stations have small on-site diesel generators, ..., which can be used to start larger generators..., which in turn can be used to start the main power station generators
Fun fact: high voltage fuses have explosives in them to make sure they disconnect properly, as high voltage can jump through air if the gap isn't wide enough.
Dingo_The_Baker t1_itogwh4 wrote
>I assume the "heroism" at your company is related to the fact this
>
>didn't happen in Texas, so whoever still had power lines could still get power.
That's what my understanding was. We were very closes to catastrophic failure of the whole system and the techs out in the freezing cold working with the control centers to stop the complete failure and limit the damage. If were going to call anyone "heroic" there it would be the techs in the field. Its not like Texas has anyway to clear or salt the roads for them to get where they needed to go.
At the time it was happening all i knew is that my power was turning off and on every 45 minutes and my boss basically told our entire team to sit home and ride out the storm as our job functions were not needed that week, even if we would have had power to do them.
Also, fuck all the politicians that refuse to upgrade our system.
Summersong2262 t1_itolwjj wrote
It's a heavily deregulated grid, after all. Private industry at work.
SnooFloofs3486 t1_itp0xd6 wrote
This is the core problem. It's a single interdependent system. With no central planning like we have in other regulated electric systems the Texas failure is expected.
The reason is that generation is HIGHLY capital intensive and the generation needed for the tail risk events is uneconomic to own for anyone, but very economic for the system. It's this way because as long as that marginal generator exists the market prices stay too low. So on is own the generation isn't going to run many hours and will never make enough revenue. But in a systemic look it becomes economic because it's value to the system during tail events is so high and the entire system that benefits pays for the value during all hours.
In competitive deregulated energy markets this is the natural outcome - under building generation for peak or design day loads.
685327594 t1_itpjzw6 wrote
The majority of the country is deregulated.
SnooFloofs3486 t1_itq8i2h wrote
It doesn't happen overnight. We're seeing this in Texas and California now. It takes time for these markets to mature.
Incidentally they're also more expensive than regulated integrated markets
685327594 t1_itqajtp wrote
The issues in Texas and California are more to do with their political posturing than deregulation.
SnooFloofs3486 t1_itqrt2n wrote
They're polar opposites politically. It's an inherent part of the nature of deregulated generation. It's just a pretty straight forward math problem to show that there is a financial disincentive to maintain enough generation for low probably events when the generation is viewed in isolation.
This is compounded by the use of gaussian statistical models for nongaussian probability - like forecasting weather extremes. So the extreme events are underestimated.
But most importantly it's also compounded by the cost of capital. In rate of return regulated markets the cost of capital is lower across the board (that's why they provide cheaper service). Cost of capital is much lower for the capital projects targeted at the low probability events. Those are risky investments in deregulated matters and require high returns. So they don't pencil out as viable commercial projects. In regulated markets those facilities are ordered by the regulators and have a guaranteed opportunity to earn a fair return. The fair return on equity being much lower because of the low risk.
The result is that regulated markets with integrated utilities and good regulation tend over time to both lower cost and more reliable.
xmaddoggx t1_itpbi0p wrote
Yeah your Texas politicians and by extension the majority of the residents in your state are to blame. Texas is unregulated because they want to be independent from the federal regulations.
Dingo_The_Baker t1_ito3pgn wrote
TIL. Like I said I'm a desk monkey trained to do a specific task, and my boss gave me the dumbed down version that I'm probably not recalling 100%.
[deleted] t1_ito6oxz wrote
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[deleted] t1_itoj54i wrote
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685327594 t1_ito5kdh wrote
They don't have fuses, lol. Computers monitor the load and trip the lines off it it gets above what they are rated for.
immibis t1_ito6lk2 wrote
Are you sure they don't have fuses as well?
SnooFloofs3486 t1_itp14lt wrote
Every wire is a fuse with enough current.
685327594 t1_ito6uh2 wrote
Yes, 100% sure.
operationfailed t1_itoj0w0 wrote
I’m guessing it varies by region but in the places I’ve worked in Canada the power lines are all controlled with circuit breakers which in turn are controlled by older electro-mechanical relays or newer digital relays. Also a lot of lines have fuses protecting them on top of that
dbuzman t1_itpa5rk wrote
Yeah, they are wrong. The pole right by my house has a fuse on it.
685327594 t1_itpjm45 wrote
Your pole isn't a high voltage transmission line.
fupa16 t1_itokg57 wrote
This is Texas we're talking about remember. They're light-years behind having advanced technology like fuses.
2daysnosleep t1_itor29z wrote
😂
dbuzman t1_itp9rsp wrote
Some lines do have fuses. There is a power pole about 50 feet from my house and it has a fuse. I have been on the front porch when the fuse blew. It was very loud. Just google power pole fuse and look at the pictures.
Hon3y_Badger t1_itpspar wrote
Yeah I don't think most people realize that the TX grid being shut down in 2021 was the "good alternative;" the other alternative being decidedly worse.
DrMooseknuckleX t1_itnk5kv wrote
This is the right answer.
685327594 t1_itnkodz wrote
It's honestly still too optimistic. Even making it one hour seems unlikely with no human input.
DrMooseknuckleX t1_itnl9kv wrote
Yes, but it includes the human element that is needed. All the others arw like "a gas/wind/nuclear" plant can produce X power for X time, without the human element of diverting and channeling the electricity. Sure the plant can keep producing, but that doesn't mean anything if it just overloads the grid.
685327594 t1_itnlrjr wrote
It includes that element, but still underestimates it. People here don't seem to realize just how little this process it automated.
PHL1365 t1_itnt03m wrote
I can see where modern plants would have some type of "dead-man switch" or "heartbeat" safety system where it would shut itself down if there were no human responses to periodic prompts.
685327594 t1_itnttg7 wrote
There's no "dead man's switch". The issue is simply the ephemeral nature of electricity. For the grid to work everything has to remain in perfect balance. It really doesn't take long for it to drift of course without a guiding hand.
Ishidan01 t1_itos37p wrote
>For the grid to work everything has to remain in perfect balance.
As all things should be.
/you may now discuss the effects of only 50 percent, instead of all, of the operators and technicians disappearing without warning
PHL1365 t1_itnw0pm wrote
Well, in theory, that balance could be achieved through software/automation. But it would not be considered reliable enough to run without some level of human oversight. Kind of like Tesla's self-driving mode.
usmcmech t1_itnz3z6 wrote
In theory yes it could.
However in reality it means phone calls from the grid managers to individual power plant control rooms.
“Hey we need you to take 500MW offline in 30 minutes”
Snoo57672 t1_itogq1k wrote
Yep. Happens every morning. Then they call me that night and ask for it right back. We wouldn't even make a shift change before the grid shit
J_Zephyr t1_itnnsdl wrote
In America, we would have people charging lightbulbs and tossing them into boxes haphazardly. Cause that's how power work.
woodshores t1_itosesj wrote
I work with wind energy.
Turbines are more complex than a car, and have oils and cooling systems. They have to be inspected on a weekly basis.
If there’s no one supervising them, they would wear out within the first weeks and permanently stop working.
immibis t1_ito247y wrote
Both power spikes and brownouts should causes systems to automatically "trip" offline. Power plants and substations have sensors to detect if the voltage, frequency, or current is out of spec - and shut themselves down, or at least disconnect themselves from the grid. Maybe some areas would happen to be in balance with their local power plants for a little while and would stay running.
KirkSheffler t1_itol42b wrote
Solar and wind also requires techs to maintain and update regularly, usually with IT people as well to program all of the gear to do what it needs. As an electrician I could confidently say not more than 1-6m with no people at all. There’s usually constant presence or maintenance techs that rotate and keep everything up to date/ running
EscapeRich9091 t1_itrgpcx wrote
... I did say until they break down? Either software failure, generator failure, bearing failures, blade failures, whatever it is. They will have an average unmaintained life expectancy probably on the scale of months.
KirkSheffler t1_itrhkrb wrote
Yes but they break down a lot faster than people think. They require constant presence like any other electrical sub stations
EscapeRich9091 t1_itrk7j5 wrote
I don't know what that unmaintained life is so I didn't address it. I'm sure somewhere they've decommissioned wind/solar/green installs and run some units into the ground to find out, but I haven't investigated to see if there's any published white papers on it.
KirkSheffler t1_itolaij wrote
And solar doesn’t drop off in the evening, it’s all stored into batteries and converted into AC for use in homes/ businesses. It’s very rare if none exinsistant to have straight power from solar.
EscapeRich9091 t1_itrgiul wrote
I'm talking about Grid scale Solar and residential Net Solar, not residential or commercial Solar + Li-ion. If you're off-grid with your Solar + Li-ion you don't factor into grid loading anyway, unless you have high energy processes, like an industrial facility which uses Solar + Li-ion for office power and grid for like arc furnaces or something really energy hungry.
Solar does drop off hard in the evenings, and it's a big problem they call "The Duck Curve". Go ahead and check out some of the online papers about it.
KirkSheffler t1_itrgu8k wrote
I understand that and it’s the same concept/ principles. They have techs who monitor and rotate between the fields keeping them in order/ up and running. The company I work for ‘Faith Technologies’ is huge into green power, and we actually did the largest solar farm in the US. I’m just speaking from personal experience working on them it may be different overseas or in different regions.
EscapeRich9091 t1_itrjvs6 wrote
As far as I know, Grid-scale li-ion (or lipo more likely) installs are super rare. A quick google says in 2021-2022 there was only 16gW of grid scale li-ion/lipo storage. Our peak usage is on the order of terawatts.
KirkSheffler t1_itrh0ij wrote
And yes there is a huge dip at night but during the day the fields are charging battery banks not using raw solar so at night if you’re not consuming a large amount of electricity it’s fine. And the banks can usually last a while on a single charge
Fign t1_itouilw wrote
This is assuming that the demand for power will remain the same. If the scenario of a post apocalyptic city is considered maybe and just maybe the load balancing against renewables scenarios is not that bad.
EscapeRich9091 t1_itrit4t wrote
That's correct, since OPs question was just if the power companies abandoned their post, not if 99% of all people died or whatever.
lordofmemesoverlords t1_itp1sz6 wrote
I think it's misleading to assume that wind and solar could potentially satisfy demand during the day.
Wind and solar account for respectively 5.3 and 2.7% in the world electricity mix.
We still live in a world powered by coal and gas (sadly).
Therefore, since 90% of the electricity production requires operator, the moment they abandon their post, production decreases very quickly and since solar and wind can't satisfy demand, the grid breaks down and you have a black out (which you can't repair without humans).
EscapeRich9091 t1_itrjayd wrote
What I said was:
> The main issue here is that even states where Solar and Wind dominate during the day
... which is specifically states like California in the US, not Global. I can't speak to the global grid because I have no knowledge. In CA 60-80% of daytime energy production can be Solar, so it dominates the grid behavior.
usmcmech t1_itnyrkj wrote
The Texas grid came dangerously close to this in 2021.
JesusStarbox t1_itokngx wrote
What about hydroelectric?
leuk_he t1_itpebk6 wrote
The 100! scenario, where they build a bunker close to a hydroelectric plant.
EscapeRich9091 t1_itrfoui wrote
There's always going to be some residual power generation. If there's a small town-scale Grid which is powered exclusively by hydro, there's a good chance it could run for a decently long time, but they need some way to offset a relatively constant energy production into the peak hours.
Hydro has some of the same problems above - it doesn't respond to load demand, and if it's on a hybrid Grid, it'll have the same Solar problem.
It's actually a big problem in our energy industry right now: The Duck Curve. https://www.cnet.com/home/energy-and-utilities/the-duck-curve-the-cute-sounding-energy-problem-well-need-to-fix/
We've deployed so much Solar that the Peak energy generation needed (outside solar) is about 2x the minimum (which happens during midday when the sun is highest). That's a huge swing in non-Solar energy demand.
Even without the Duck Curve problem, your night time demand is going to be about 30% less than your day time demand.
So if your Hydro is scaled to handle Peak demand, you would have to shed all that night time power somewhere, or have an Operator close the sluices which feed the generator turbines a bit, to scale back the energy.
If your Hydro is scaled to handle Off-peak/Night demand, you would end up with Brownouts and possibly Blackouts during the day as Grid demand far out-strips generation and you end up back like Texas in 2021.
Edit: Basically the first person to solve and patent an efficient and inexpensive way at Grid scale to store excess Solar from the day to use at night is going to become the richest person in the world ever.
[deleted] t1_iton93d wrote
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Tamaska-gl t1_itorhy3 wrote
In BC we are something close to 99% hydroelectric power (even the power company is called BC hydro) so we shouldn’t require this switching, does that mean our power grid would run longer without human intervention?
SnooFloofs3486 t1_itp1ezd wrote
No. There's still a control room deciding how much water to flow. It possibly could be fully automated, but hydro on my system is still operated via the control room by humans. My guess is that yours is too.
EscapeRich9091 t1_itrihqo wrote
If they've fully automated control, it could. But I doubt they have. Grid loading is actually pretty noisy... things like overall weather, temperature, wind gusts, even clouds passing over Solar farms, or large industrial consumers which could be taking in 1-2% of your load... the energy generation operators have to work to match that load as it gains and sheds and typically keep a little (but not too much, because it costs money) extra power generation above what is current needed to respond to micro-spikes, in addition to ramping and up and down with the day.
For example, on your average summer day if it's 30C out, you're going to need a lot more power than on a nice fall day where it's maybe 17C out and nobody is running air conditioning or heating. For a computer to predict that load and match it consistently to the generated power isn't easy.
Maybe they're doing it? But I think it's much, much more common for there to be a control room. There's further aspects to this, because we're glossing over how power grids actually work - there's a bidding process for energy that happens and the energy generators (wind, solar, power plants, hydro, whatever) will ramp up or down their energy contributions to the grid both based on load demand but also on energy pricing. Maybe in BC your utility is not for profit and that's not part of it, but in the US it certainly is a big deal.
In the end, it would run longer even if fully automated, but things like hydro plants are insanely complex. Without regular maintenance and inspection they're not likely to outlast a Wind or Solar farm.
Funny enough, small scale hydro (<10kW) with battery intermediates can be insanely reliable and maintenance free. I've seen reports of off-grid installs basically running for years with no maintenance other than clearing off leaves from the intake every 6mo or so.
jericon t1_itp4lsc wrote
In Texas some of the issues were also due to the cost of fuel being more than the electricity it would produce. So some plants chose to go offline.
daveatc1234 t1_itpmhkr wrote
Thanks for this awesome explanation. VERY cool. There is a great video about this, and more broadly what would happen if we all just disappeared one day.
agate_ t1_itnv2li wrote
There's a really great book called "The World Without Us" by Alan Weisman that goes into detail about this and other related questions about how long the relics of humanity would stick around if we all disappeared.
He argues that the power would go out almost everywhere inside 24 hours. Power plants really do have a "driver" who decides how much to "step on the gas", and while there's some automation, a lot of the decisions happen by humans and involve manual work, like bringing new generators online as electricity use varies over the day, running a bulldozer to shovel coal into the loading hopper, and so on. If nobody does this, supply doesn't match demand, the grid gets overloaded, and circuit breakers start to trip. That shifts the load to other parts of the grid, overloading them and causing a cascading chain reaction. (This can happen even when the power workers are doing their jobs!)
Anyway, if you liked "Station Eleven", do check out "The World Without Us", it's a scientific look at the post-apocalypse and it's pretty great.
larsattacks94 OP t1_itnxd8r wrote
Thank you so much! Just ordered the book, very excited to read it!
hypatiatextprotocol t1_itoh547 wrote
This book is very good! I found it surprisingly peaceful to read descriptions of the earth continuing without us.
Best of luck to the animals currently in their Stone Age, inc. New Caledonian crows, macaques, and robust capuchin monkeys.
Tdabp t1_itpcedy wrote
There's a YouTube video on it. Nicely detailed.
KaTaLy5t_619 t1_itntbil wrote
Less than a day. There is a lot of human monitoring and intervention required to operate a large power grid successfully.
Let's take where I live for example, Ireland. Grid operators are aware of any major event that is taking place such as a World Cup Soccer match and would be waiting to release excess capacity into the grid when the half-time whistle sounds to counteract people all across the country boiling their kettles at almost the same moment.
One way of managing this is pumped storage, where water is pumped up to a reservoir during low demand periods (usually during the night) and releasing the water through turbines to generate more power when required before pumping it back up to the reservoir but this has to be triggered by the grid operator.
What would happen if the grid operator didn't release extra capacity into the grid when required?
The supply frequency and voltage need to be carefully regulated as straying too far away from the nominal values will lead to a bad time. Imagine the grid is like a car engine with a manual transmission and the customer demand is like the road. When the engine power and gear selection matches your speed and road conditions, you travel along smoothly.
Now imagine you come to a steep hill (this is the extra demand on the grid), the driver (grid operator) should drop down to a lower gear and put their foot on the gas (extra capacity) to get up the hill smoothly but let's say the driver has fallen asleep. The engine (grid) will start to slow down as the hill (demand) becomes steeper. The engine will start to labour and eventually it will cut out.
This is an oversimplification of what would happen to the grid but it's not a million miles off. Without compensating for increased demand or reduced supply (if a generator trips offline) the voltage and frequency will start to drop off which causes the current to increase and this will trigger overloads on downstream circuits. Upstream, as the generation stations see the grid frequency and voltage fall, they might also trip offline to protect against damage from mismatched frequencies.
Lots of modern circuit breakers can be set to auto-close after a trip so the circuits would attempt to come back on but after another trip they might go into fail safe that can only be reset manually.
You might get large parts of a city or state going into blackout which might temporarily solve the extra demand issue as the load has been shed but, depending on how many generation stations tripped offline, you might already be into a cascading failure type situation where more and more generation stations trip offline until there's nothing left online.
frustrated_staff t1_itndbj6 wrote
Yes, and it depends. Is it a gas plant, a coal plant, a solar plant, a hydro plant, a nuclear plant? A plant of near-future design other than those I asked about?
larsattacks94 OP t1_itnfeo6 wrote
They didn't go into details about it. It's from the perspective of a violin player 20+ years after a pandemic
zzyl53 t1_itnghyj wrote
Just curious, what’s the name of the book?
larsattacks94 OP t1_itngtob wrote
Station eleven. It goes back and forth from day of the pandemic to 20+ years after. Very good highly recommend
TravelingChick t1_itnjfi1 wrote
Great book!
larsattacks94 OP t1_itnjkz2 wrote
I'm almost done with it. But so far it's been great. Couple times them talking about the pandemic hit a little to close to home
juancuneo t1_itowqyu wrote
There is an HBO series. I am halfway through. For some reason it makes me sad and I have to stop watching it. But it’s an amazing show so I keep watching in 15-20 minute increments. I may have to check out the book.
larsattacks94 OP t1_itpiw4g wrote
I didn't know there was a show. I'll have to check it out when I'm done with the book
Vogonfestival t1_itptg5f wrote
It gets better and more hopeful as it goes on
frustrated_staff t1_itnjv0l wrote
In that case, it's probably a gas plant, and...depending on its supply and whether or not anything has gone wrong, those can (generally) keep going for years without intervention. On the other hand, no supply = no power AND anything goes wrong = no power
So...it's probably not the plant operators leaving that caused the outage, especially since the grid is hyper-connected. It's probably a lack of fuel supply, from the refineries abandoning their posts...at least, if it's based in reality
musk1266 t1_itoby3u wrote
Most gas plants require hydrogen to cool their generators, if the supply of hydrogen runs out then the plants shut down automatically, or worse. Typically hydrogen is provided in a trailer that is dropped off every couple weeks. Speaking from experience a plant that runs on a hydrogen trailer would probably shut down in 2 days if nobody was around to put new hydrogen cylinders into service.
frustrated_staff t1_itp20sh wrote
I did not know that...cool
LegendOfBobbyTables t1_itnkeke wrote
You are going to start seeing power failure pretty quickly. Coal power is very hands on, and they just won't keep chugging along for very long without humans keeping them running. Maybe 48 hours assuming power demand falls too.
The transmission lines are the real issue. They are constantly failing and being repaired. Without people fixing the lines, power can't get where you need it anyways.
In a post apocalypse type scenario, most of North America is going to be on fire pretty damn quick, and that is going to take out long distance power transfer. Our entire modern society is built around having rapid response to any fires. Our cities will burn down within days or weeks without firefighters.
kinyutaka t1_itnd6ly wrote
Usually it would, but without people to maintain the plant, eventually fuel would deplete or connections get broken or wires go down or something else, and the power grid kind just stops.
Even without an apocalyptic event, i would be surprised if the lights stayed on for a week without someone manning the equipment.
larsattacks94 OP t1_itnflxr wrote
A week really? That is surprising. In the book they say it was day 20 when the lights go out. Thought it seemed so short but seems like they over did it
CrossP t1_itngxtj wrote
It probably depends a bit on the kind of plant. Like if it's coal, it has to keep being moved into the furnaces. Not necessarily daily, but they get deliveries and refill the setup from storage pretty regularly. Something without fuel like wind, hydro, or solar would probably go until some piece of maintenance isn't performed.
tarkinlarson t1_itnjw37 wrote
I heard thag nuclear would autoshutdown, but something like hoover damn would carry on until the turbines physically broke, so could be decades before a cstestrophic failure.
There are a few documentaries on it like if humans suddenly disappeared.
CrossP t1_itnlbuv wrote
The turbines in a hydroelectric dam station would probably go for a long time, but the connection to the actual grid may not be so robust. Wires. Transformers. Lubes. Coolants. Connectors. There's always something that can break or run out. The systems are usually made to make this work simple, but there still has to be someone who checks the readings, and replace stuff or some critical bit will stop the electricity from working correctly.
685327594 t1_itnl2b7 wrote
That's wrong on multiple levels. First off the units WOULD trip offline and second if they didn't they would physically break as soon as the grid went down because there would be no load on the generators.
immibis t1_ito4cvu wrote
Wouldn't there be a control system that would reduce the water flow to prevent the turbines going faster than normal?
soniclettuce t1_itoanwk wrote
There's been previous reddit threads where nuclear operators have said that current plants are generally not "walk-away safe". They claimed you'd have about a week before they'd be in danger of meltdown.
usrevenge t1_itnm14g wrote
It would probably be a few hours tbh.
The grid has to be balanced. If your town starts using more power a power plant somewhere in the network has to spool up more generators or increase their speed.
If a power plant suddenly goes offline the power plant has to call the regional area offices and tell them so they can balance the load. I've been in a plant where this was happening a lot. Even if this wasn't automated it could easily fail somewhere. The electric grid is one of the most complicated pieces of infrastructure in the country.
kinyutaka t1_itngebh wrote
To be fair, I am not an expert on these matters. I would be surprised if it goes for a week, because our power grid died without the abandon ship just because it was too cold.
I would call it "believable"for 20 days, I just expect less.
685327594 t1_itnh85p wrote
No, that's completely unbelievable.
kinyutaka t1_itnifka wrote
I am sure it depends on a lot of factors.
Some plants might go down in a heartbeat. Some might coast a bit. Like the Hoover Dam Hydroelectric Plant probably can run for a bit, especially since electrical demand would go down after an apocalypse.
I do not want to test that, though.
685327594 t1_itninez wrote
Demand going down is bad too. The plants will trip offline either way.
Maeghkor t1_itnjhpi wrote
Care to explain whys that?
685327594 t1_itnk9we wrote
Without any load the turbines will start to accelerate. The protection systems will automatically trip the plant offline before it accelerates out of control and destroys itself.
khalcyon2011 t1_itnlfqb wrote
Basically, the power has to go somewhere, so if demand drops, the system cycles off. I imagine it's automated, but starts and stops are wear and tear on the system. And things might get gummed woke it's down. Further, the start up systems need power, so there's another point of failure.
RedtheGamer100 t1_itnmt2w wrote
What book
larsattacks94 OP t1_itnwpfc wrote
Station eleven.
RedtheGamer100 t1_itnykaz wrote
Ty
wintermute93 t1_itnxm06 wrote
If you want a nonfiction account of events would likely proceed if the grid suffered massive widespread failure, read "Lights Out" by Ted Koppel.
685327594 t1_itnfc5c wrote
If everyone abandoned their post the power grid would fail in a matter of minutes. Supply and demand have to match every second and without someone adjusting the supply you would pretty quickly get a mismatch large enough to trip off the entire grid.
tired-space-weasel t1_itng0ub wrote
That's pretty much automatic, you don't manually turn knobs in a power plant to change the output.
Source: studying electric power engineering
AustinYun t1_itnk9ea wrote
That seems to run contrary to the accounts I've read of for example the Texas winter blackout.
685327594 t1_itnkhby wrote
Because it's straight up bullshit.
immibis t1_ito4ro6 wrote
I think it's somewhat automated but not completely. They call it droop control, yes?
685327594 t1_itng7w2 wrote
No, you literally do turn knobs to control the power level. Hell, at a nuclear plant you literally have to choose every step of every control bank you want to move.
Salindurthas t1_itngh5y wrote
>Supply and demand have to match every second
This can be somewhat automated though. Like the signal for needinging more/less energy gets sent to the control-electronics in the power-plant, which then control the water/gas/air flow, or disconnect/reconnect solar panelts, etc.
Now, whether that means it lasts for twice as many minutes as you guessed, or for hours or days, is unclear to me. But it is plausible to me that it could last substantially more than mere minutes.
And even if things start to trip, that can be limited in scope. Like maybe one suburb gets a black out at peak time due to not enough manual upkeep, but the rest of the grid might continue ok.
Liz_zarro t1_ito0li4 wrote
There are entire courses that cover the automation you're describing. Controllers that manage the I/O of large complicated systems are really difficult and expensive to automate due to the varying delays, gain rates, and trip scenarios that go into programming these things. This is something strong AI might be able to do some day but presently there's an asymptote to exactly how much automation you can put into a system due to either cost or complexity.
If you go look at some of the behind the scenes videos or TV specials of energy distribution, you'll see that there are a lot of correlations these operators are tracking when it comes to anticipating overall power consumption. There's a notable one about how they time the power generation in Britain with the breaks in certain television programs because a large number of people tend to turn on their electric kettles at the same time. If a computer waited until it sensed the frequency started to drop they'd overload the grid before they could ramp up production to meet demand.
These are big generators with a lot of input lag. Without anticipation of potential real world cause/effects you wouldn't be able to program enough gain to ramp up capacity for load spikes. Set the gain too low and the controller is too slow to increase output quick enough. Set the gain too high and it will ramp up for every small dip causing oscillating spikes and dips as the controller overcorrects around the target value.
I'm currently working with a small setup to control a gas flare/evaporator setup and that extremely limited system is still around $60,000 just in programming alone. We're talking about four motors,maybe a dozen block valves, and more sensors than you'd expect. The cost for automating something as big as a power plant would be in the tens of millions of dollars and it would be somewhat bespoke to each plant. You can cover a lot of man hours with that money and probably get better efficiency while you're at it. All the subsystems would be automated to a pretty good extent but right now you just can't beat having a human working the knobs and levers.
685327594 t1_itngli7 wrote
It CAN be, but it isnt..
Omegaprimus t1_itnjblg wrote
Yeah that is true, the electrical grid in the US has to be manually maintained in near real-time. Honestly it shouldn’t as a computer could handle this with no problems at all, but the systems to control that are not in place. Most power plants require power from elsewhere to run, with the exceptions of PV Solar, and some windmills the small ones not the big ones those require power to position themselves. Nuclear, forget about it, if the grid failed the plant would instantly go into standby followed by an automatic shutdown.
larsattacks94 OP t1_itnfx56 wrote
That's so surprising. I would have figured at least a few weeks running on auto pilot until something slipped up
685327594 t1_itng084 wrote
What autopilot?
OwnDragonfruit8932 t1_ito4aqr wrote
If you watch “Life after People” it gives a speculation by days and months and years what would happen if we all vanished. The book “The World Without Us” is another one. So interesting
JessicleK t1_itoasxl wrote
I love that series. My main takeaway was that our whole infrastructure is held together by paint. It will hold up for a while but once it breaks down and the rust starts it all comes crashing down.
(Also, I hope that when all the people disappear the cats can come with us, that part of the story was the most upsetting)
OwnDragonfruit8932 t1_itrr5dx wrote
Ya I agree. I hope all the animals come with us.
Luxcrluvr t1_itobqlp wrote
I realize people think utility workers at plants just sit around and watch fancy lights and gauges 😂
KurtWagnerX t1_itoqe2c wrote
I remember a speculative documentary series called "Life After Humans"" which tried to imagine what would happen to civilization if humans all just suddenly disappeared one day.
They suggested that Hoover Dam could keep producing electricity unmanned for weeks or months. In fact, I think they said the first thing to cause a failure there would be an invasive mollusk species (barnacles, maybe?) in the Colorado River that grows in the channels of the dam that have to be constantly scraped out.
leuk_he t1_itpep0c wrote
Also I wonder what happens to the nuclear plants. Many were build 30-50 years ago based on proven (old) technology. If you shut them down, they need to be cooled a considerable time. If you not shut them down, they need water in their reactor at all times.
In fukushima they shutdown the cores and then lost power, leading to blowing up some of them because of low water isssues or cooling issues, and no automatic venting.
mytthew1 t1_itpopbd wrote
I read the Hoover dam would supply power for 18 months. It is automated but at some point requires maintenance. I have zero experience to confirm this.
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SpectralMagic t1_ito5hvo wrote
Common Solar panels lose efficiency at ~1% annually if I recall correctly. You'd need to replace them in the long term, and possibly find a better source of energy production like hydro and wind. Obviously that's nothing if you're powering just for yourself, and who's to say they won't last 80+ years with minimal wear. Just sharing a small thought about solar in a world where you can't produce more of them
Rosieapples t1_ito7ddf wrote
It wouldn’t be without people for long, there would be an onslaught of electricians, engineers etc promptly moving in to keep the power going
Kihr t1_itoaib0 wrote
Depending on season, you would probably be longer in the spring/summer as the load peak to trough is lower, but if it was summer you'd black out midday. Same in winter.
Source: former grid operator
Waxingsharks t1_itqox6d wrote
That begs the question, in an apocalyptic even how hard would it be to restart or partially start the grid up again? Like if some survivors found the control room or whatever and wanted to restore power to their camp specifically should it fall in the grid, what obstacles would they have to overcome?
Kihr t1_itrev4x wrote
It'd be incredibly difficult even if we had a nationwide blackout. There are 3 grids and they all have different issues.
musk1266 t1_itocfyt wrote
Most likely the plants would shut down, the major issue for many turbines is the fact that they have hydrogen in the generators to cool them off and require seal oil to keep the hydrogen in there away from anything else (especially oxygen). If the transmission line goes and there is no power backfed to the plant the seal oil pumps will shut off, the hydrogen will then escape the generator and mix with oxygen causing an explosion that will basically destroy the generator itself.
Coming_In_Hot_916 t1_iton3lx wrote
So what book are you reading? I’m looking for something new in this genre.
aurinxki t1_itozmmp wrote
I'm curious too. "Blindness" by José Saramago mentions a situation like this in passing.
larsattacks94 OP t1_itpiyy3 wrote
Station eleven
bandanagirl95 t1_itondd6 wrote
It sort of depends on the definition of "abandoned their post". If they shut it down on the way out, about 15 seconds if coal is involved.
If they don't shut it down on the way out, you'll run in to issues as soon as the load no longer roughly matches what is generated, either way. This is because the entire system is designed under the assumption that these will roughly match. If they don't, generators and other equipment can end up destroying themselves. This imbalance will almost certainly happen within about 12 hours. Everything would start catastrophically failing sort of like as happened with the Texas grid a year or so ago (though they got that under control before it was an enormous issue)
kozlee t1_itorjjj wrote
Are you reading Alas, Babylon?
larsattacks94 OP t1_itpiwzw wrote
Station eleven actually
beardyramen t1_itp0pa7 wrote
Almost instantly. Consider that most grids are designed to work in a way that power generation and consumption MUST always be equal.
This means that we constantly fine-tune the power output of power generation plants.
We loose this, we stop receiveing energy in our homes.
We would still be able to generate it, but our grid wouldn't be able to work with it.
This need will be compensated in the future with solid energy storage systems spread across the grid. Consider that the unpredicatability of renewables concurs in this balancing complexity.
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Mobely t1_itpp2oz wrote
Instantly. If you abandon your post, you shut things down first so nuclear reactors don’t go supercritical
explainlikeimfive-ModTeam t1_itppk6w wrote
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[deleted] t1_itodaq3 wrote
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EscapeRich9091 t1_itnj371 wrote
Solar and Wind will continue to operate until they break down... but the Grid which distributes it relies heavily on human input to route around issues and balance the supply to demand, even with lots of automation around it.
The main issue here is that even states where Solar and Wind dominate during the day, our power mostly is coming from coal and natural gas at night. And those big plants need human operators.
Without those operators, what you'd see is power issues during the day, since Solar and Wind can overwhelm the Grid without dumping excess peak power, or momentarily dip causing instability. As Solar falls off in the evening, brownouts would occur as Wind would be insufficient to supply the entire Grid, and the fossil-fuel plants would not ramp up to match evening demand without human operators, so they only supply a trickle of idle power generation.
Brownouts would progress rapidly to full blackouts within a day or even hours as Grid demand far outstrips the supply, which will cause irregular loading on the remaining availability, tripping fail-safes/grid breakers/etc., and causing the Grid to shut itself down, which can't be restarted easily.
A real life example of partial abandonment is visible in the 2021 Texas power grid failure. Operators weren't able to get into work due to conditions. Supply lines and trains and trucks carrying fossil fuels were disrupted and delayed. Grid instability due to unmatched demand caused the whole thing to fall over (they shut it down before total failure which would require a very slow "black start"). It took about 2 days for this to all unfold as back to back storms hit the state, and well over a week for most of the capacity to be restored.
There are some automatic green-power storage systems which would allow small subsets of the Grid to continue to operate, like large scale batteries, or pumped storage using water and gravity to capture excess Solar. But without Grid operators to selectively shut down sections, the demand would rapidly outstrip those kind of storage systems and we'd see similar end results, maybe lasting a few days more, but hard to guess without examining particular cases.