In general, slowing frequency is an indicator of a heavily loaded grid. I don't have an appreciation how much the frequency can practically be off the nominal 50 Hz (in Europe) before it indicates grid failure.
does this happen if the heavy load is at region scale? because at small scale (within a village in my experience) the voltage would drop. I didn't measure the frequency though.
This is fascinating to me. What is the mechanism by which this happens? The added load causes an average slow down across the population of actual spinning generator bits?
That's exactly right. Extra electrical draw on the grid (or a loss of electrical production elsewhere) causes the turbines in power plants to physically spin slower due to increase load on each turbine.
An (imperfect) analogy would be if you and a friend were biking up a hill on a tandem bike. If a third person hopped on the handle bars (or your friend stopped pedaling) the bike's wheels would slow down, assuming you are putting a constant amount of power into the pedals.
Tangentially (or maybe tandemially :) this illustrates the problem of synchronizing an e.g. solar power unit delivering to the net. The person jumping on a multicycle in speed must synchronize their feet to the rotating pedals to actually add power.
Most power generators are rotating engines (there are exceptions like solar and and batteries that use power inverters).
Increasing load decreases frequency exactly the same way as anything rotating slows down when you increase load. Electric grid is like chain in a bike. Generator producing power leads a little. Loads follow little behind. They are not exactly matched. Like bike chain is tighter to one direction and looser to other under load.
Mass of rotating generators provide kinetic inertia into the grid so it reacts very little to small variations in the load. But if the load becomes too high and turbines can't speed up, frequency of the grid slows down.
In practice it depends a lot on how a bunch of specific power equipment is set up.
Remember that the A/C power grid needs to be synchronized across the entire continent, so each A/C generator that makes A/C power and runs at 50Hz needs to have the position of a physical object (the rotors) match the position in the current power cycle. If it's badly wrong, you have power-plant sized energy feeds fighting each other — imagine a train wreck, two massive oversized freight trains smashing right into each other. It's like that, but with electricity instead of a physical collision.
This can obviously cause major damage, so once you start deviating from the reference frequency by enough, it's safer to just cut off the interconnects and go offline.
Under 49Hz they start disconnecting consumers. If that does not stabilize the dropping, under 47.5 Hz they disconnect the power plants and the network fails. [1]
I didn't feel like reading a low effort anecdote about that one time someone tried to run their house off of some rooftop solar and a golf cart battery and all his ceiling fans slowed down and everything died when the fridge kicked on so I figured I'd bring load based frequency reduction into the discussion on my own terms.
I can't think of any practical way to use that much power all at once either. On a small country size grid with a lot of renewables that can't ramp quickly I could see some foundries pulling it off.
I know your joking but it's been dead for more than 30 years :) Only the antenna remains (and the only one still standing was the receiver, not the transmitter).
Though people have hooked up amateur radio equipment to it AFAIK.
The grid was overloaded significantly, but not critically. For everybody concerned with the grid, this is a major event because the grid is usually extremely stable.
For everybody else, it's not significant. Grid operating as designed.
> If I haven't miscalculated, then this waste means the #Netzfrequenz that there was a sudden drop in power of over 4.5GW. That would be a lot more than a power plant. So junction could get there.
At least 3 large power stations. But is that necessarily a loss of supply or could it be a spike in demand? The UK was famous for demand spikes when people turned on kettles during the break in popular soap opras or football games. Maybe a cold day tripped a bunch of houses to turn on their electric heating?
Fun fact: your water company probably has TVs in the control room specifically so the operators can now when those flush breaks are coming up and ensure the water towers have enough water at those times.
(I interned at a water treatment plant a while ago. Watching the 30 million gallon cleartanks drain when the plant lost power really hit home (at ~6-7 million gallon/hr) how much water an entire city uses.)
CNPE Graveline[1] (a French Nuclear powerplant) Cattenom, and Paluel are >5GW, so it could actually come from a single plant (not that I think this is the case, this is just for the sake of argument)
> Extreme nightcap in the #network frequency.
Quite unusual at this height and at this point in time. One of my measuring devices even shows 49.74Hz as a minimum. Has a major #power plant failed somewhere?
And second tweet:
>Here is another representation of the # mains frequency from just now. Extremely unusual, as a malfunction is to be suspected.
Unfortunately, none of my network analyzers are currently running to check the exact course.
My German is limited to introductory conversations and ordering food, so I'm not really sure what's going on with this case. It does, however, look like the warning signs were there.
Romanian news are screaming about several counties (like 1/5 of RO) being blacked out and this being a problem at the interconnection with the neighboring power grids.
From the little I know about power lines, events like this can cascade to half a continent.
were. I think it's mostly fixed for residential by now. The news says the incident happened at 15:05 local time (12:05 gmt? 13:05? damn daylight savings) and power was restored to all affected by 16:45.
Industry may be still shut down, there was some chemical plant that had to perform an emergency shutdown which released some crap in the air. They say it's non toxic though.
> Water fell at that time, so maybe some hydro was shut down?
That was my first reaction on /r/romania, too, but some commenter in there suggested that maybe the hydro power production went down as a result of the network not being available (no reason to "pump in" electricity if there's no available network to transport it).
FYI, in English, "news" is singular, e.g. "I saw a politician shouting on the news", so it should be "Romanian news is" (and I think it should also have a "the").
I know this makes no sense and in other languages "news" has both singular and plural but that's English for you.
Serbia is currently only consuming ~30% of the usual power, Bosnia and Montenegro are at 60%, Croatia 50%, other neighbouring countries had quiet some spikes as well.
Some large energy consumers that also have slow processes (so they can survive a temporary blackout) have contracts that give them cheaper electricity, and in exchange the electricity company is allowed to just cut them off for some time, if load gets too high.
It seems like a better solution would be batteries and/or the allowance of dirtier power generation (in emergencies). I can't even wrap my head around the regulatory nightmare of shutting off everyone's heat at night in January.
Batteries maybe. Allowing "dirtier" non-50Hz power would make things worse, power plant turbines are optimized for 50Hz, different frequencies get inefficient quite fast. So your generation will shrink the lower you go. At the same time generators running at different frequencies will work against each other. At the same time machines will pull the frequency down even further, landing you in a vicious circle that forces the frequency toward 0Hz. No choice but to cut power before you damage too much of the grid and equipment.
Perhaps I don't understand the grid properly. I thought the average frequency was always maintained at 50Hz over a 24 hour period. Having the frequency dip below 49.9Hz would normally be exceptionally rare.
I mean, if the alternative is a blackout, having heating turned off for a few minutes over a 24 period would be preferable to a nationwide blackout? It's not as if people would suddenly freeze to death anyway.
Just curious if someone who understood this better had a good explanation for why this might be a bad idea.
Dirtier power generation doesn't work because physics. Frequency gets too high (a few Hz or so), turbogenerators/turbines blow up. Frequency gets too low, resonances destroy them. Frequency shifts quickly, massive torque and current spikes ensue. Load is dumped, frequency ramps up quickly and voltage rises very quickly. There are a number of control and monitoring systems in a power plant which ought to prevent these from happening, but in the bigger picture this means that grid power needs to be balanced continuously in order to keep nominal frequency. This becomes challenging when an interconnect fails, because this leads to very fast load changes.
The reason for 50 Hz +- 0.2 Hz isn't so much about consumers; it's about being able to run the grid. In Europe there is a long-term control loop that makes it a quite accurate 50 Hz, so synchronous motor clocks work, but that has essentially nothing to do with the normal frequency control.
"Dirtier power generation doesn't work because physics. Frequency gets too high (a few Hz or so), turbogenerators/turbines blow up. Frequency gets too low, resonances destroy them."
You very obviously have no idea what you are talking about.
Turbines blowing up because they spin a few Hz faster? Mine never did. Turbine destroyed because of "resonances" when freq too low? Mine never did that either.
Not the 1100MW one at my old job, nor the two 500MW ones at the job before that and also not the 12MW one at my current job.
Hey, could you please review https://news.ycombinator.com/newsguidelines.html and stick to the rules when posting here? It's not ok to attack another user like that on this site, regardless of how wrong someone is or you feel they are.
It sounds like you know a lot about this topic, which is great, but please omit personal swipes—that will make it much easier for people to learn from your posts.
It’s all about speed. A power grid must be perfectly balanced at all times, there no natural storage in a power grid.
If large power supplier disconnects without warning, that impact propagates at the speed of light. Other suppliers will respond by reducing their frequencies to keep voltage up, this is caused by generators physically spinning slower and converting their physical momentum into electrical energy. As you can imagine the momentum of a generator is large, but the stored energy is small compared to the rate of consumption.
So you need systems that can respond within milliseconds to restore some stability. Batteries are actually one of the few technologies that can do that, but mostly your looking at shedding load. Disconnecting a consumer can happen in milliseconds, after all you just need to flip a switch (admittedly they’re very large switches).
Once you shed load, then you have the time you need to spin up you “dirty” power supplies. But even the fastest response suppliers take minutes (think Hydro), not milliseconds to respond. So they’re not viable for dealing with the initial shock to the grid.
It’s tends to be very viable. Most places can afford for heat to be shut off for 10-15mins without issue (think water heaters and whole building heaters).
That then gives the grid some time to spool up reserves. After all having your hear turn off for 10mins is better than having everything turn off for an hour, which could happen if the grid needs to shed load involuntarily.
Most grids have a rapid response system like this. They’ll have contracts with very large power consumers (think big hydro pumps, metal smelters etc) that can afford to have their equipment power down without notice in exchange for energy rebates.
Then when the frequency drops these consumers will automatically turn off their equipment to reduce power draw.
The seeing such a huge drop like this is extremely unusual, no doubt many systems immediately started load shedding (both voluntary and involuntary) to compensate
Apparently first threshold for cutting of hydro storage pumps below 49.85 Hz was undercut very briefly. Immediately afterwards the frequency reaches that threshold again, so I assume those measurements were working as planned.
Below 49Hz larger consumers would be cut off in steps of ~10% of the network load. AFAIK this includes large industrial consumers who are legally required to have the equipment in place to allow for that.
Industrial consumers will have a contract to be part of first tier load shedding, rather than a legal mandate.
If the grid really needs to shed load, it doesn’t ask, switchgear will just be programmed to physically disconnected consumers at certain grid frequencies. As a consumer you should have equipment that can survive that if it’s important to you, the consumer can then normally get rebates for loss of service later.
Special locations like hospitals are normally the last to be load shed, and the surrounding grid will shed everyone else first, before disconnecting them.
This needs central coordination to really work. You also need customer incentives to get buy in.
Power companies do something similar with air conditioning units in hot areas. Customers can opt-in to have a control module installed that modulates their A/C on and off at peak loads to control demand. Customers get some nominal discount on their bill for participating.
Worked better when people weren’t working from home and it didn’t matter if your house was a bit warmer than normal for an hour or two mid-day.
Controlling this on end devices introduces a lot of distributed systems problems, like stampeding herd when all of the devices switch back on. You could try jittered back off and such, but cold customers would just unplug and replug until it worked.
The term in the industry for this is "demand response," and usually it's voluntary and customers should get paid for participating.
Typically it's just larger customers that can reduce demand on a very large scale. In the US there are a few startups that are aggravating residential customers into larger groups, so that each of thousands of households cuts consumption by a few hundred watts, so that the aggregate drop is big enough for the utility to care about. Utilities, at least in the US, have extremely poor capabilities for innovation and for customer relations, so that is why a startup is an intermediary.
Typically, the signal for this is not the grid frequency, however! Better to plan ahead by a bit before the frequency drops, and allow people to opt out as necessary.
For rapid response systems grid frequency is the signal!
You always need something that can respond quickly to unexpected events to maintain grid stability. The best signal for that is grid frequency, as it’s a very direct measure of grid health.
Many of those large consumers you speak off will be contracted to respond directly to grid frequency, either shedding load or adding supply, to make sure the grid doesn’t completely collapse if a shock event happens. That buys grid maintainers the time they need to recover the grid in a more controlled way.
German press reports about cold temperature and of not enough nuclear power online in France. Reason: maintenance backlogs due to Corona. 44 of 56 reactors are online, next week only 43.
They'll may import up to 12 GW electricity from Switzerland and Germany.
People are meant to be sharing heating in an office building during the day.
I have a wood fire, and I usually have enough wood stacked in summer to make it through winter. Last year I was out in the cold chopping because we had the fire on all the time.
While true, it's very unlikely to be the reason for what we're seeing here (a sharp drop at 14:05), it's most likely related to a plant failure (likely a nuclear / hydro plant) somewhere in Europe.
It's also more than ususally cold here in Barcelona, and many people have electric heating (inefficient but rarely needed).
I don't know what I'd do if the power fails :S I have UPS power backup for my servers but not for heating obviously (that's way too much power for batteries)
I want to get rooftop solar and a battery pack for my house. But I really don't want to a lithium battery attached to my house. I feel like there'd be a good business in selling battery 'space' in a big fire proof box down the street that I could then offset my meter against.
Wouldn't even need to be in my street if I could get the offset.
I get where you are coming from, but my car is already a ~50 kWh lithium ion battery in my garage, so I'm already living with that fire risk. I just wish I could use my car to power my house when there's a power outage, it's a big enough battery to last for a couple days even when it's at half charge.
Why does it have to be lithium technology? The reason electric cars use it is because of energy density (weight savings). For home use, weight is completely irrelevant. You could use much safer lead acid batteries (sealed/AGM) and rig your own inverter setup. This is also a lot easier to maintain over time, as you can scale up/down and swap individual batteries as required.
Certainly doesn't have to be lithium. But for frequent cycling, lead acid is more expensive. Lead acid also requires occasional maintenance to keep the acid levels topped up.
But if you want to rig you leave own setup with lithium ion, scaling up and down with smallish individual battery units over time, those are available for sale. The list prices I've seen are pretty high, about $700/kWh, however. An integrated unit can be cheaper. And as lithium ion battery prices plummet over the next two years, and factories scale, the home storage market will hopefully start to get access to $300/kWh products or cheaper.
I like these stories because they make me remember that things like electricity and water are not free.
Water and electricity should be a lot more expensive, then people would start to understand that having an Electric car, 10+ devices in the household, a washer, a drier, lights, tvs and all that shit is expensive for the lot.
But people don't really care, as long as our things work and we are not bothered by anyone else.
So you want people to use gas cars and gas-powered boilers to heat their home? Or should we make that more expensive as well so we can make sure more people spend more time with heating off in the winter?
Isn't a gas-powered heater more efficient than an electric heater powered by an LNG plant? Electric heating is pretty ineffective, although heat pumps can work well.
It might be, but it's also depleting a natural resource that refills _really_ slowly. Electricity at least can be (though is often not) generated from resources that do renew, like solar and wind energy.
It is, but this is one of the areas where synthetic fuels would be useful. Airplanes are another, since batteries are heavy and worse don’t get lighter as you use up the charge.
Apparently there is some research in synthetic natural gas, which is an unfortunate name.
Water and electricity should be a lot more expensive, then people would start to understand
In combination with educating people not to waste these sources, perhaps. Even then, just a fixed rate might not actually do it: don't recall the exact numbers but just like some small percentage of the entire population earns most, there's also a certain percentage who spend (or waste, depending on how you look at it) more of these sources and because they have the money anyway, making things more expensive will not hit them at all. Instead the lower end of society will take a hit. Which is of course part of the idea, but for some of them that might actually be the extra costs leading to not being able to pay all bills anymore or worse. tldr; I'm not entirely convinced yet, but it seems that to solve problems like this a system where those who use most pay extra (think: you wanna fille your huge pool with drinking water? you'll pay)
Maybe. Some of the "continental" grid is in Africa, the above second map doesn't color in Russian bits of Europe, and then there are the other European grids. But the high bit is that there are significant parts on not this grid, there are 6-ish grids.
All of Europe's national grids are interconnected, and most of them import or export more than 10% of their power budget (some both, depending on the time of day). A large power fluctuation/blackout in one country can easily spread to neighbouring countries, the junctions can't absorb the sudden shift in network load.
It doesn't really matter if people keep their vehicle for decades, because people usually sell their old vehicles for use by others when they get a new (to them) vehicle.
What you want to know is the average life of a vehicle (or average age of the fleet), not the average period of ownership.
I'm sure that varies by country; IIRC Germany has punative taxes on registering old cars, so their average age should be a lot less than in the US where registration tax usually is based on value, so goes down as the vehicle ages. I seem to recall average fleet age of about 20 years in the US.
The average age of operating automobiles in use within the US is closer to 12 years. The registration fee (annual renewal, not initial registration) in the US is based on vehicle value in 8 states by my count.
On a personal note, me and most of the people I know think more in terms of miles than years. I figure every car I buy is good for 200,000 miles and most of the brands I favor have another 100,000 miles of life beyond that before repairs exceed some loosely calculated rate of return.
> On a personal note, me and most of the people I know think more in terms of miles than years.
I think that partly depends on how you drive and where you live. I'm in a snowy climate: my engine might have no problem going 250,000 miles, but there's virtually no chance the body is drivable after 30-40 years of rust.
With that, I tend to buy a car in years, for example: "I'm hoping to have this for the next 6 years".
You haven't used it for decades yet. Decades start at 20 years. They just start there. If people used their cars for 40 years, then it would apply more honestly.
heat pump are highly inefficient if outside temp gets below ~5 degC and that's what happening right now on most of Europe ( incl. southern europe, I saw spain mentionned here ... )
Heat pumps are always at least as efficient as resistive heating, but do have less efficacy when the ambient temperature goes below their design parameters.
Standard heat pumps these days work great even at 5C, at least any one that I have seen.
The H2i line from Mitsubishi maintains 76% of its COP down to -25C (-13F).
This UK document specifically mentions phasing out "high carbon fossil fuel heating" installations in new construction, which seems like the sort of thing the GP referenced, though it also mentions heat pumps as a non-resistive-heating option: https://www.gov.uk/government/groups/heat-in-buildings
I live in a tropical climate so I'm completely clueless on heating systems but has municipal steam heating been completely abandoned? It seems more efficient than both individual gas or electric heaters once you take conversion loses into account
Would say that almost all cities / larger towns in Sweden has municipal heating via hot water. And acc. to wikipedia around half of all housing units in Denmark, Sweden and Finland has municipal heating.
That's strange, here in Sweden electric heating is seen as old and wasteful. In cities most use district heating, others use heat pumps or some kind of bio fuel. At least for new houses, but it's also common as a retrofit.
That just means that you can't max out all your circuits at the same time. I'm pretty sure that's considered normal.
If instead of FIR panels you use a heat pump (isn't that the main point of electrical heating), would you still need 32A? And if you're cooking and baking with 10 kW, would you still need heating at the same time? And a 7 kW heat pump water heater should give you ~10 liters per minute of hot shower water.
Seems like any automatic system that could make sure not all high-draw consumers get turned on at the same time would be enough. It does mean that if someone is taking a shower while two people are vacuuming with all the lights on and the kitchen is cooking up a feast, you wouldn't be getting any additional heat or electric car charging, for the hour or so that such high demand can last, but that doesn't seem to be a serious problem (especially as this would only affect older houses).
And you said it's required for new construction, so I assume they'd be putting in 3-phase for those.
The main power lines for the whole street could be a problem, so yes, this may require some new construction. Might as well put down FTTH while at it.
Additionally, if houses add solar, it should reduce typical demand on the grid, as a lot of the current wouldn't have to flow all the way from some substation but would be supplied either within each house or from neighbors.
How do FIR panels compare to heat pumps in terms of energy efficiency? Are they really able to reach similar comfort levels at much lower temperatures as advertised?
$9k buys a three zone ductless multi split heat pump, installed, in a area with very high labor costs. This heats and cools and can modulate to a reasonable degree. (This price is for a Fujitsu system — I don’t know the price for other vendors.)
Maybe you can install a cheaper FIR system, but that system is actually just electric resistance heat. Sure, maybe you can operate in a regime where the mean radiant temperature where you are is enough higher than the actual air temperature to save some power, but that had better be a pretty big effect to overcome the 3-4x efficiency improvement of a heat pump. And did I mention that the heat pump can cool, too?
The point is that electricity allows to change energy source anytime and be carbon neutral.
Yes, the issue is not plugging in some resistance. Infrastructure should be adequate. Hence, it makes sense to do it right in newly built houses. Upgrading existing buildings will also be necessary. It will also solve the EV charging.
There's no other way to replace fossil energy but to increase electrical power use. 1954 assumptions about maximum household power and current
thresholds are no longer valid.
What do you mean by bad planning. Are you talking about planning that is flexible and responsive to pick up the slack. For example, a high demand day that is cloudy and not windy?
I am talking about designing a grid to be robust, and has enough spare capacity to handle difficulties without failing catastrophically.
For critical infrastructure, you design for worst-case scenarios, inflate the safety margins, and make backup plans (like a plan to gracefully degrade service).
Failing this and cutting corners is what I would call bad planning.
It is unfortunately true that intermittent sources of power generation subtract from grid stability. Texas (ERCOT region) had a huge incident back in 2019 with rates skyrocketing to $9/KWh for over 90 minutes. Many attributed this to an over-reliance on wind generation.
The average duration of power outages in Germany has been on a steady decline over the last 15 years [1]. The fraction of electricity generated from renewable sources has increased from around 10% to over 40% in the same period of time [2].
There is a very nice ongoing effort at the University of Tennessee Knoxville to monitor the US power grid. http://fnetpublic.utk.edu/
The video is 10 years old, but depicts a box with GPS timekeeping, and sampling the normal outlet, with Ethernet to report to the server. https://www.youtube.com/watch?v=9Vt2OlVoBJc
145 comments
[ 5.7 ms ] story [ 224 ms ] threadAn (imperfect) analogy would be if you and a friend were biking up a hill on a tandem bike. If a third person hopped on the handle bars (or your friend stopped pedaling) the bike's wheels would slow down, assuming you are putting a constant amount of power into the pedals.
Increasing load decreases frequency exactly the same way as anything rotating slows down when you increase load. Electric grid is like chain in a bike. Generator producing power leads a little. Loads follow little behind. They are not exactly matched. Like bike chain is tighter to one direction and looser to other under load.
Mass of rotating generators provide kinetic inertia into the grid so it reacts very little to small variations in the load. But if the load becomes too high and turbines can't speed up, frequency of the grid slows down.
Remember that the A/C power grid needs to be synchronized across the entire continent, so each A/C generator that makes A/C power and runs at 50Hz needs to have the position of a physical object (the rotors) match the position in the current power cycle. If it's badly wrong, you have power-plant sized energy feeds fighting each other — imagine a train wreck, two massive oversized freight trains smashing right into each other. It's like that, but with electricity instead of a physical collision.
This can obviously cause major damage, so once you start deviating from the reference frequency by enough, it's safer to just cut off the interconnects and go offline.
[1] https://www.netzfrequenzmessung.de/abschaltung.htm
I can't think of any practical way to use that much power all at once either. On a small country size grid with a lot of renewables that can't ramp quickly I could see some foundries pulling it off.
[1] https://en.wikipedia.org/wiki/Duga_radar
The drop was around ~4.5GW
Though people have hooked up amateur radio equipment to it AFAIK.
This graph shows the frequency drop we encountered: https://www.netzfrequenzmessung.de/bilder/2020_01_08_Abschal...
The red line at 49Hz is when things actually get switched off for the first time (12.5% of load).
https://twitter.com/netz_frequenz/status/1347537615097049101...
https://www.reddit.com/r/soccer/comments/28mmsn/water_usage_...
(I interned at a water treatment plant a while ago. Watching the 30 million gallon cleartanks drain when the plant lost power really hit home (at ~6-7 million gallon/hr) how much water an entire city uses.)
[1]: https://en.wikipedia.org/wiki/Gravelines_Nuclear_Power_Stati...
[2]: https://en.wikipedia.org/wiki/Cattenom_Nuclear_Power_Plant
[3]: https://en.wikipedia.org/wiki/Paluel_Nuclear_Power_Plant
> Extreme nightcap in the #network frequency. Quite unusual at this height and at this point in time. One of my measuring devices even shows 49.74Hz as a minimum. Has a major #power plant failed somewhere?
And second tweet:
>Here is another representation of the # mains frequency from just now. Extremely unusual, as a malfunction is to be suspected. Unfortunately, none of my network analyzers are currently running to check the exact course.
https://www.mobilityhouse.com/int_en/magazine/company/tmh-wo...
https://www.armstrongeconomics.com/markets-by-sector/energy/...
[1] https://www.netzfrequenzmessung.de/aktuelles.htm#2021_01
That’s why this is so scary
https://finance.yahoo.com/news/u-k-power-grid-creaks-0951256...
From the little I know about power lines, events like this can cascade to half a continent.
Instead of 220V we got down to ~165V.
Internet outages on top (I assume some hardware failed since multiple counties were affected on the RDS network).
Edit.
Here's a power graphic: https://www.transelectrica.ro/widget/web/tel/sen-grafic/-/SE...
Seems Romanias production fell under the consumption at around 15:30
Water fell at that time, so maybe some hydro was shut down? We did have multiple floods reported yesterday.
But the incident started at 15:05, that was just a consequence of interconnects failing i think.
Are homes experiencing brownouts? Or is it only in the distribution system?
Industry may be still shut down, there was some chemical plant that had to perform an emergency shutdown which released some crap in the air. They say it's non toxic though.
That was my first reaction on /r/romania, too, but some commenter in there suggested that maybe the hydro power production went down as a result of the network not being available (no reason to "pump in" electricity if there's no available network to transport it).
I know this makes no sense and in other languages "news" has both singular and plural but that's English for you.
the romanian blackout is linked to the european one
[1] https://www.reuters.com/article/serbia-kosovo-energy/serbia-...
Serbia is currently only consuming ~30% of the usual power, Bosnia and Montenegro are at 60%, Croatia 50%, other neighbouring countries had quiet some spikes as well.
It is my understanding that modern home EV chargers have the capability to do this to some extent, but I'm not sure if it's actually utilised?
I mean, if the alternative is a blackout, having heating turned off for a few minutes over a 24 period would be preferable to a nationwide blackout? It's not as if people would suddenly freeze to death anyway.
Just curious if someone who understood this better had a good explanation for why this might be a bad idea.
The reason for 50 Hz +- 0.2 Hz isn't so much about consumers; it's about being able to run the grid. In Europe there is a long-term control loop that makes it a quite accurate 50 Hz, so synchronous motor clocks work, but that has essentially nothing to do with the normal frequency control.
You very obviously have no idea what you are talking about. Turbines blowing up because they spin a few Hz faster? Mine never did. Turbine destroyed because of "resonances" when freq too low? Mine never did that either. Not the 1100MW one at my old job, nor the two 500MW ones at the job before that and also not the 12MW one at my current job.
It sounds like you know a lot about this topic, which is great, but please omit personal swipes—that will make it much easier for people to learn from your posts.
If large power supplier disconnects without warning, that impact propagates at the speed of light. Other suppliers will respond by reducing their frequencies to keep voltage up, this is caused by generators physically spinning slower and converting their physical momentum into electrical energy. As you can imagine the momentum of a generator is large, but the stored energy is small compared to the rate of consumption.
So you need systems that can respond within milliseconds to restore some stability. Batteries are actually one of the few technologies that can do that, but mostly your looking at shedding load. Disconnecting a consumer can happen in milliseconds, after all you just need to flip a switch (admittedly they’re very large switches).
Once you shed load, then you have the time you need to spin up you “dirty” power supplies. But even the fastest response suppliers take minutes (think Hydro), not milliseconds to respond. So they’re not viable for dealing with the initial shock to the grid.
If you do it for 5 minutes while the gas plants spool up, few will notice and fewer will care.
That then gives the grid some time to spool up reserves. After all having your hear turn off for 10mins is better than having everything turn off for an hour, which could happen if the grid needs to shed load involuntarily.
Then when the frequency drops these consumers will automatically turn off their equipment to reduce power draw.
The seeing such a huge drop like this is extremely unusual, no doubt many systems immediately started load shedding (both voluntary and involuntary) to compensate
Below 49Hz larger consumers would be cut off in steps of ~10% of the network load. AFAIK this includes large industrial consumers who are legally required to have the equipment in place to allow for that.
If the grid really needs to shed load, it doesn’t ask, switchgear will just be programmed to physically disconnected consumers at certain grid frequencies. As a consumer you should have equipment that can survive that if it’s important to you, the consumer can then normally get rebates for loss of service later.
Special locations like hospitals are normally the last to be load shed, and the surrounding grid will shed everyone else first, before disconnecting them.
[1] - https://www.netzfrequenzmessung.de/abschaltung.htm
Power companies do something similar with air conditioning units in hot areas. Customers can opt-in to have a control module installed that modulates their A/C on and off at peak loads to control demand. Customers get some nominal discount on their bill for participating.
Worked better when people weren’t working from home and it didn’t matter if your house was a bit warmer than normal for an hour or two mid-day.
Controlling this on end devices introduces a lot of distributed systems problems, like stampeding herd when all of the devices switch back on. You could try jittered back off and such, but cold customers would just unplug and replug until it worked.
Typically it's just larger customers that can reduce demand on a very large scale. In the US there are a few startups that are aggravating residential customers into larger groups, so that each of thousands of households cuts consumption by a few hundred watts, so that the aggregate drop is big enough for the utility to care about. Utilities, at least in the US, have extremely poor capabilities for innovation and for customer relations, so that is why a startup is an intermediary.
Typically, the signal for this is not the grid frequency, however! Better to plan ahead by a bit before the frequency drops, and allow people to opt out as necessary.
You always need something that can respond quickly to unexpected events to maintain grid stability. The best signal for that is grid frequency, as it’s a very direct measure of grid health.
Many of those large consumers you speak off will be contracted to respond directly to grid frequency, either shedding load or adding supply, to make sure the grid doesn’t completely collapse if a shock event happens. That buys grid maintainers the time they need to recover the grid in a more controlled way.
https://www.lefigaro.fr/conso/electricite-pour-eviter-des-co...
https://www.connexionfrance.com/French-news/People-in-France...
Britain, too:
https://uk.news.yahoo.com/britains-national-grid-issues-warn...
German press reports about cold temperature and of not enough nuclear power online in France. Reason: maintenance backlogs due to Corona. 44 of 56 reactors are online, next week only 43.
They'll may import up to 12 GW electricity from Switzerland and Germany.
https://www.fr.de/wirtschaft/droht-frankreich-ein-blackout-9...
Edit: according to https://news.ycombinator.com/item?id=25685833 it means that there's more than 4GW went missing, which rules out a hydro plant failure and make nuclear plant failure unlikely (only three plants, all of them in France, would be big enough for that and there was no drop in French electricity production today: https://www.rte-france.com/eco2mix/la-production-delectricit...)
I don't know what I'd do if the power fails :S I have UPS power backup for my servers but not for heating obviously (that's way too much power for batteries)
https://twitter.com/Amprion/status/1347595605971972100
But if you want to rig you leave own setup with lithium ion, scaling up and down with smallish individual battery units over time, those are available for sale. The list prices I've seen are pretty high, about $700/kWh, however. An integrated unit can be cheaper. And as lithium ion battery prices plummet over the next two years, and factories scale, the home storage market will hopefully start to get access to $300/kWh products or cheaper.
Water and electricity should be a lot more expensive, then people would start to understand that having an Electric car, 10+ devices in the household, a washer, a drier, lights, tvs and all that shit is expensive for the lot.
But people don't really care, as long as our things work and we are not bothered by anyone else.
Pretty much like this
Apparently there is some research in synthetic natural gas, which is an unfortunate name.
In combination with educating people not to waste these sources, perhaps. Even then, just a fixed rate might not actually do it: don't recall the exact numbers but just like some small percentage of the entire population earns most, there's also a certain percentage who spend (or waste, depending on how you look at it) more of these sources and because they have the money anyway, making things more expensive will not hit them at all. Instead the lower end of society will take a hit. Which is of course part of the idea, but for some of them that might actually be the extra costs leading to not being able to pay all bills anymore or worse. tldr; I'm not entirely convinced yet, but it seems that to solve problems like this a system where those who use most pay extra (think: you wanna fille your huge pool with drinking water? you'll pay)
Example: my house, a 1954 built semi-detached - the official average unit in England - has a single phase 100A main cutout.
Hob 32A, 2x sockets circuits 2x16A, 2x light circuits 2x6A, oven 16A. That's already 92A at total theoretical capacity.
If I was to add FIR panels, that's bare minimum +32A, plus water heating - let's play it down, +32A, car charger +32A again.
This means I'd need a 3 phase extension. If everyone in the area were to do this we'd literally burn down the system on day one.
Not only that, but they insist that almost all vehicle transportation should be electric in maximum 10-15 years.
Even at that point it’ll still be decades before electric vehicles make up the majority of road traffic.
What you want to know is the average life of a vehicle (or average age of the fleet), not the average period of ownership.
I'm sure that varies by country; IIRC Germany has punative taxes on registering old cars, so their average age should be a lot less than in the US where registration tax usually is based on value, so goes down as the vehicle ages. I seem to recall average fleet age of about 20 years in the US.
On a personal note, me and most of the people I know think more in terms of miles than years. I figure every car I buy is good for 200,000 miles and most of the brands I favor have another 100,000 miles of life beyond that before repairs exceed some loosely calculated rate of return.
I think that partly depends on how you drive and where you live. I'm in a snowy climate: my engine might have no problem going 250,000 miles, but there's virtually no chance the body is drivable after 30-40 years of rust.
With that, I tend to buy a car in years, for example: "I'm hoping to have this for the next 6 years".
Which governments are those?
It should be the same in Europe and it will work in case the temp drops too low.
Standard heat pumps these days work great even at 5C, at least any one that I have seen.
The H2i line from Mitsubishi maintains 76% of its COP down to -25C (-13F).
EDIT FIR = far infrared, eg. https://www.herschel-infrared.co.uk/
If instead of FIR panels you use a heat pump (isn't that the main point of electrical heating), would you still need 32A? And if you're cooking and baking with 10 kW, would you still need heating at the same time? And a 7 kW heat pump water heater should give you ~10 liters per minute of hot shower water.
Seems like any automatic system that could make sure not all high-draw consumers get turned on at the same time would be enough. It does mean that if someone is taking a shower while two people are vacuuming with all the lights on and the kitchen is cooking up a feast, you wouldn't be getting any additional heat or electric car charging, for the hour or so that such high demand can last, but that doesn't seem to be a serious problem (especially as this would only affect older houses).
And you said it's required for new construction, so I assume they'd be putting in 3-phase for those.
The main power lines for the whole street could be a problem, so yes, this may require some new construction. Might as well put down FTTH while at it.
Additionally, if houses add solar, it should reduce typical demand on the grid, as a lot of the current wouldn't have to flow all the way from some substation but would be supplied either within each house or from neighbors.
EDIT: for <5k I'd have the whole house on FIR panels and electric boiler, then I could spend another 5k on solar.
Maybe you can install a cheaper FIR system, but that system is actually just electric resistance heat. Sure, maybe you can operate in a regime where the mean radiant temperature where you are is enough higher than the actual air temperature to save some power, but that had better be a pretty big effect to overcome the 3-4x efficiency improvement of a heat pump. And did I mention that the heat pump can cool, too?
Yes, the issue is not plugging in some resistance. Infrastructure should be adequate. Hence, it makes sense to do it right in newly built houses. Upgrading existing buildings will also be necessary. It will also solve the EV charging.
There's no other way to replace fossil energy but to increase electrical power use. 1954 assumptions about maximum household power and current thresholds are no longer valid.
https://www.current-news.co.uk/news/national-grid-eso-issues...
If central planners didn't subsidize renewables there wouldn't be as many problems.
For critical infrastructure, you design for worst-case scenarios, inflate the safety margins, and make backup plans (like a plan to gracefully degrade service).
Failing this and cutting corners is what I would call bad planning.
[1] https://www.bundesnetzagentur.de/DE/Sachgebiete/Elektrizitae...
[2] https://www.umweltbundesamt.de/themen/klima-energie/erneuerb...
The video is 10 years old, but depicts a box with GPS timekeeping, and sampling the normal outlet, with Ethernet to report to the server. https://www.youtube.com/watch?v=9Vt2OlVoBJc
One of the best real time views, is this view of the phase across the US. http://fnetpublic.utk.edu/anglecontour.html
"System split registered in the synchronous area of Continental Europe – Incident now resolved"
https://www.entsoe.eu/news/2021/01/08/system-split-registere...