[HN Gopher] System separation in the Continental Europe Synchron...
___________________________________________________________________
System separation in the Continental Europe Synchronous Area on 8
January 2021
Author : andreasley
Score : 262 points
Date : 2021-01-26 09:58 UTC (13 hours ago)
(HTM) web link (www.entsoe.eu)
(TXT) w3m dump (www.entsoe.eu)
| tyho wrote:
| How does this affect timekeeping? Normally, if there is a drop in
| grid frequency, a small increase will be planned later to
| maintain a long term average frequency of 50Hz so that clocks
| that keep time by grid frequency stay accurate [0].
|
| The network split seems to have made this impossible, during the
| split, the cycle counts for the two regions diverged, and the
| split ended before this was reconciled. Will people in one of the
| regions have to adjust their clocks?
|
| [0]:
| https://en.wikipedia.org/wiki/Wide_area_synchronous_grid#Tim...
| i_am_proteus wrote:
| My suspicion is that NTP (and GPS) have generally superseded
| the synchronous grid for timekeeping. It has for every
| application that I know of.
|
| Simultaneously, I suspect some systems still do rely on grid
| time.
| nottorp wrote:
| Computers (or anything containing a proper computer) don't
| care about grid frequency for time keeping.
|
| On the consumer side, your microwave, coffee machine and even
| bedside clock will.
|
| Not sure on the industrial side.
| read_if_gay_ wrote:
| > your microwave, coffee machine and even bedside clock
| will.
|
| I guess a ~0.5% deviation for a couple minutes is going to
| be tolerable here.
| nottorp wrote:
| Oh found it. Looks like this went on for more than a
| couple minutes:
|
| https://www.theguardian.com/world/2018/mar/08/european-
| clock...
| LeonM wrote:
| The grid is never exactly 50Hz, it varies quite
| significantly. On the long run, the grid operators try to
| average to 50Hz as close as possible, just so that clocks
| continue to operate somewhat accurate.
|
| In fact, it is even in the FAQ of the article:
|
| "The transmission grids of the countries of Continental
| Europe are electrically tied together to operate
| synchronously at the frequency of approximately 50 Hz"
| driverdan wrote:
| Based on the article the control limits are 49.8 to 50.2
| Hz (+-0.2hz). That's less than 1%, not very significant.
|
| One of the places I lived in Austin, TX had a range with
| a clock that used grid frequencies (60hz in the US). It
| was dead accurate. I only changed it for daylight
| savings, it never need adjustment.
| klodolph wrote:
| The US used to guarantee 5,184,000 cycles per day. That's
| not, like, 1% or anything comparable, that's zero (with
| temporary deviations). Any clock which referenced line
| frequency would be dead accurate over the long-term.
| There's a system called Time Error Correction (TEC) which
| would do this (refer to WEQ-006 and the like). Obviously
| this error is measured relative to some reference clock.
|
| I'm not sure what the current status is, but my
| understanding is that there are efforts to retire this
| system and allow the speed to drift more.
| jwr wrote:
| > On the consumer side, your microwave, coffee machine and
| even bedside clock will
|
| I'd be _very_ surprised. It 's cheaper to build in a
| 32.768kHz crystal for timekeeping than try to access the
| grid frequency from the isolated low-voltage circuit.
| garaetjjte wrote:
| I don't think price is significant factor. It just needs
| optocoupler, diode and few passives.
| klodolph wrote:
| You don't need an optocoupler to measure grid frequency.
| You can just use a resistor. Dirt cheap, cheaper than a
| crystal.
| garaetjjte wrote:
| Yes, but OP talked about isolated circuits. It's likely
| that most appliances don't need to be isolated though.
| sltkr wrote:
| It is very true.
|
| A similar event happened in Europe a year ago (also due
| to problems in former Yugoslavia) and all electric clocks
| in my house (microwave, oven, alarm clocks) went out of
| sync temporarily. I was just as surprised as you.
|
| Basically, it's exactly the devices that lose track of
| time in case of a power outage, and that you need to
| manually adjust for daylight savings time, that are
| synchronized to the grid. Devices that use a battery
| (such as laptops, mobile phones, and CMOS clocks in PCs)
| must necessarily use some other means.
|
| It doesn't seem to be much correlated with price either:
| my alarm clock cost over $100 and it was still affected.
| Surely at that price point they could have afforded a
| crystal oscillator in the design, if they wanted to, but
| it seems this just isn't typically done.
| laurent92 wrote:
| As an industry, it requires a special customs declaration
| + fire safety measures on boats and planes when you
| transport an oven with a battery inside. That may be the
| reason for not using battery-backed ovens, and relying on
| the power supply.
| fuzzer37 wrote:
| Just curious what kind of alarm clock costs $100
| sltkr wrote:
| Something like this:
| https://www.amazon.co.uk/dp/B008LR3KD8/
|
| The idea is that it wakes you up gently by flooding the
| room with light resembling a natural sunrise. One reason
| that it might be expensive is that it needs a lot of high
| luminance hue shifting LEDs, and possibly I overpaid a
| bit (there do seem to be much cheaper competitors) but it
| was still a good investment because it does make my
| mornings a lot more pleasant.
| ficklepickle wrote:
| One that plays soothing sounds, like dogs barking or
| seagulls fighting over trash, probably.
|
| It might even project the moon phase on the ceiling.
| iSnow wrote:
| At a $100 price point, I'd expected a DCF77 receiver tbh,
| not a crystal oscillator.
| ardy42 wrote:
| >> On the consumer side, your microwave, coffee machine
| and even bedside clock will
|
| > I'd be very surprised. It's cheaper to build in a
| 32.768kHz crystal for timekeeping than try to access the
| grid frequency from the isolated low-voltage circuit.
|
| IIRC, the grid frequency is usually more accurate.
| Probably because it's carefully monitored and managed by
| the power authorities like the OP describes. If you build
| a clock with its own frequency reference, than any error
| will accumulate and have to be monitored and managed by
| the user.
| userbinator wrote:
| _It 's cheaper to build in a 32.768kHz crystal for
| timekeeping than try to access the grid frequency from
| the isolated low-voltage circuit._
|
| Those products don't use isolated power supplies ---
| normally they use a capacitive dropper. A high-value
| resistor to an IC pin is sufficient to drive the clock
| counter, and a resistor is definitely cheaper than a
| crystal.
| alkonaut wrote:
| I have a microwave and oven from the same brand, and
| their digital clocks diverge about 2minutes in 24h. I
| just don't understand how it's possible to build a device
| that poorly in 2020 (they are new) and I also wonder
| which tech they use for timekeeping. Is it possible that
| _one_ of them uses a crystal and the other uses the 50Hz?
| That would explain a small difference.
| eqvinox wrote:
| It's easy enough to mistune a 32768Hz clock crystal by
| shitty electronics engineering, unfortunately :/
|
| 50Hz might have temporary variations, but it's controlled
| so that over a longer period of time, you always get the
| correct number of cycles, e.g. 180000 in an hour.
|
| This also means that going off the 50Hz power grid
| theoretically has better (or even perfect) long-term
| accuracy. Also means that if you adjusted your clock for
| this separation event, you'll have to adjust it back :D
| laurent92 wrote:
| US current is 60Hz. EU current is 50Hz. Maybe your over
| maker did some rounding when adjusting by 5/6 and here
| you go? Btw, does your oven have a 50-60Hz switch?
| thaumasiotes wrote:
| > I have a microwave and oven from the same brand, and
| their digital clocks diverge about 2minutes in 24h.
|
| That's much, much worse than a cheap digital watch from
| 20 years ago.
| andai wrote:
| Much worse than a digital watch from the _80s._ (Maybe
| 70s?)
| alkonaut wrote:
| I know. It's worse than the pendulum clock I have to
| crank at my grandma's once a week! Progress!
| kevin_thibedeau wrote:
| It's either a poorly made bottom of the barrel crystal or
| they cheaped out even further and used a ceramic
| resonator. That is the price of race to the bottom
| globalization. Measuring line frequency is a no go
| because the safety compliance inceases costs.
| nottorp wrote:
| Maybe, but I bet those designs are very traditional and
| date from the time where it was cheaper to use grid
| frequency.
|
| If not, why don't coffee machines that can start on a
| timer have a backup battery for their clock? That might
| be cheap enough too. And vital for those moments when
| there was a 10 second brownout which leads to your coffee
| not being ready in the morning...
| wongarsu wrote:
| > why don't coffee machines that can start on a timer
| have a backup battery for their clock?
|
| As a European the thought wouldn't have come to me.
| Brownouts just don't happen (see this 0.5% frequency dip
| making headlines), and a blackout is a once-a-decade
| event for any given house (probably even less frequent
| than that).
|
| So your answer is probably that demand for that feature
| is far from universal, and a coffee machine is much lower
| stakes than for example an alarm clock.
| labawi wrote:
| I was under the impression semaphores use grid power as a
| clock source. And the case of missing payer in southern
| Balkan got the timing shifted by a few minutes.
| brummm wrote:
| In Europe, many countries have radio signals that many clocks
| use to sync their time that is based on some atomic clocks. For
| example, in Germany these are called Funkuhr and the signal
| comes from an atomic clock in Braunschweig if I'm not mistaken.
| ficklepickle wrote:
| We have this in North America as well. The station is called
| WWVB.
|
| https://www.nist.gov/time-distribution/radio-station-wwvb
| izacus wrote:
| Clocks on our ovens and some microwaves got out of sync during
| that period. I haven't seen any other device rely on the
| network frequency for timekeeping - everything time sensitive
| is already on NTP and GPS time.
| tzs wrote:
| OT: Several commenters have mentioned both their oven clocks
| and microwave clocks getting out of sync. I'm curious as to
| why people set both of these clocks in the first place.
|
| The microwaves and ovens I've seen do not actually require
| you to set the clock. None of their cooking features and
| functionality depends on it. It's just a convenience feature.
| I doubt that most people actually need two clocks in the
| kitchen, so why not just set one of them (or neither if you
| don't need a kitchen clock at all)?
| AdamN wrote:
| There was this great design for a microwave that a UX
| designer proposed. One button for +30 seconds, no clock,
| and a door handle. That's it. Everything else is
| superfluous.
| ta76893548 wrote:
| As a person who uses a microwave a lot this sounds
| terrible, I could live with 30s resolution, but not
| having adjustable power level would not be acceptable.
| Cooking anything on 100% power is just a recipe for
| uneven heating.
| BrandoElFollito wrote:
| I have in my kitchen + living-room one clock based on NTP
| on a dashboard, one on a WiFi radio and one on the oven.
|
| Depending on where I am I see one of them so all must be
| synchronized to the millisecond so that children are not
| late to school (school is nearby, which exponentially
| raises the risk of them being late because it is just "4
| minutes" away).
|
| This is one of the scientific uses of such multiple clocks.
| Denvercoder9 wrote:
| Lots of ovens and microwaves don't allow you to disable the
| clock, so the alternative to setting them is to have them
| run out-of-sync, which is much more irritating than having
| to set them.
| tzs wrote:
| Ah...I'd forgotten about the ones that always show the
| time regardless of whether or not it has been set. I can
| see how that would get annoying.
|
| I guess I've been lucky in that all the microwaves I've
| had over the last couple of decades, and the ones we had
| at work, do not show the time unless you've set it. My
| current one, which has 7 segment LEDs for the time
| digits, blanks all the digits, leaving just the colons.
| My prior one showed "--:--" if time was not set. The one
| before that had a graphical display and just showed blank
| where the time would normally go.
| mrmanner wrote:
| Mine has two alternatives: Clock or blinking red light. I
| choose the clock...
| nslav wrote:
| I just got rid of a GE microwave which required me to set
| both the time and date before heating food after a power
| outage. I never did figure out what the date was for since
| it was never displayed and the clock did not automatically
| adjust for daylight savings time.
|
| On top of that it had a dedicated button for toggling
| between AM and PM when setting the clock, which served no
| purpose whatsoever after that point. I wish I knew what the
| designer was thinking when they came up with that.
| amaccuish wrote:
| Literally because it annoys me more having it not set
| properly
| vaduz wrote:
| I can give you a personal counter-example: my oven requires
| the time to be set to run - without it, neither the fan nor
| any of the two heating elements turns on.
|
| It's an old Bosch HBN202S
| alex_duf wrote:
| I wonder what are the benefits of keeping the grid synchronous?
|
| Would it be possible to have multiple smaller grids, still
| interconnected, but without being kept in sync?
|
| I'm not sure if what I'm saying is possible or efficient, but
| converting AC to DC, transmitting the energy, then converting DC
| to AC so the frequency becomes irrelevant.
| gspr wrote:
| For one, it's used for timekeeping.
| filmor wrote:
| That's more of a side-effect, not the goal of a synchronous
| grid.
| tsar_nikolai wrote:
| > I wonder what are the benefits of keeping the grid
| synchronous?
|
| > Wide area synchronous networks improve reliability and permit
| the pooling of resources. Also, they can level out the load,
| which reduces the required generating capacity, allow more
| environmentally-friendly power to be employed; and allow more
| diverse power generation schemes and permit economies of scale.
| [0]
|
| [0] https://en.m.wikipedia.org/wiki/Wide_area_synchronous_grid
| calaphos wrote:
| It is absolutely possible and exactly how connections between
| the different grids are done, e.g. between the power grids of
| North America or between the European grid and Russia.
|
| HVDC of course has the disadvantage of extra conversion
| equipment. HV circuit breakers are also significantly more
| complex as an arc will form as long as current is flowing. With
| AC this happens at the zero automatically, nothing like this
| with DC.
| erk__ wrote:
| Does not even need to be between countries for example east
| and west of Denmark are on two different grids which only
| recently got connected 10 years ago. (Large HVDC under the
| great belt) I am pretty sure the map on the site is "wrong"
| as Sjaelland (Zealand) the large eastern island of Denmark is
| on the nordic grid, and so is Bornholm which nearly
| exclusivly gets it power from Sweden.
| Symbiote wrote:
| The map on Wikipedia is better, as it divides Denmark
| correctly, and also excludes several other large European
| islands that are not connected to the grid.
|
| https://en.wikipedia.org/wiki/Synchronous_grid_of_Continent
| a...
| asmithmd1 wrote:
| You can see on this map the purple DC lines between England
| and France and Ireland https://www.entsoe.eu/data/map/
|
| I am amazed the grid goes all the way to Iraq
| 7thaccount wrote:
| Multiple small grids (probably not interconnected) would be
| like microgrids.
|
| In general, interconnection allows for the sharing of
| generators. My 30 year old coal unit might not need to run
| because I can buy electricity from your cheaper gas plant.
| [deleted]
| kuter wrote:
| There was a incident in Turkey (31 march 2015) that caused a
| country wide blackout. From what I understand the west side and
| the east side loose sync. The west side had under supply and the
| east side had over supply.
| huhnmonster wrote:
| I was wondering if someone could explain the countermeasures for
| such an event. Obviously, as the article states, producers are
| being shut off in the regions with surplus, while drains, who can
| afford to shut off, are shut off in the deficit regions.
|
| Is this an automatic process? Or is it more like someone from the
| company's energy provider calls them and tells them to shut off
| some devices? And is there not a potential problem, that if too
| many shut of at once, you now have a surplus again? Or is it
| coordinated by one single entity?
| paulmac_ie wrote:
| The company I work for provides Demand Response to the Irish
| grid operator.
|
| In cases like this, our systems would detect the frequency
| deviation, and shut off loads within 100 milliseonds to reduce
| the demand on the grid. This helps in cases where demand is
| greater than supply.
|
| The entire system is automated - the required time frames are
| so quick that you don't have time for humans to be involved. By
| the time we're aware that an event has occurred, we've already
| reduced demand on the grid.
|
| Handling high frequency events where supply is greater than
| demand is tricker. Sites that have long running generation can
| be instructed to shut down their generation, but large-scale
| batteries are probably the best solution in these cases. They
| can be switched quickly to start charging (if they have spare
| capacity).
|
| As you've identified, one potential issue is that you can end
| up over-responding to the event and move from a low frequency
| event to a high frequency event.
|
| The way we do in in Ireland is that our response is
| proportional to the frequency nadir. Not everything is tripped
| off at the same time.
|
| As other posters have noted, the actual frequency deviations
| that occurred are not that big. 49.7 Hz is not that low
| compared to normal grid frequency. In fact, some of our systems
| wouldn't even activate at this level. They would see it, but
| wouldn't trip off any loads.
| xoob wrote:
| I'm curious about this. What kinds of load is your company is
| running? How do you take them offline and online so quickly
| without affecting production or leading to long restart
| cycles?
| rtkwe wrote:
| They talk about it in the article as contracted interruptible
| services that got shut down in France and Italy to reduce the
| draw on the grid.
| [deleted]
| bo0tzz wrote:
| It is an automatic process, coordinated - as far as I'm aware -
| by two national energy grid providers (Switzerland and Germany)
| who have been selected for this role.
| fisian wrote:
| The response is automated and every system operator provides
| some ressources to react:
| https://en.wikipedia.org/wiki/Operating_reserve
| Faaak wrote:
| These are called ancillary services. There are 3 levels:
| frequency control (for example dams), primary reverse (fast
| acting power, in less than 10s), and secondary reserve (slow
| acting: < 15min).
|
| Participants can either be positive (they consume more energy,
| for example PHES systems), or negative (they inject or consume
| less energy).
|
| All these ancillary services are paid (annual auction + per
| case). Nowadays, it's getting bigger with VPP: virtual power
| plants, which aggregate small loads (i.e. small ~1MW
| generators) in order to propose a bigger load to TSOs.
|
| It's all automatic
|
| If you're interested:
| https://www.swissgrid.ch/en/home/customers/ancillary-service...
| Faaak wrote:
| On top of that, newer solar inverters MUST (at least in the
| EU) reduce power if frequency rises in order to automatically
| shed power in cases of extreme supply
| Reason077 wrote:
| "Shutting off drains" is known as _demand side response_ or
| DSR. It 's often cheaper, faster, and more environmentally
| friendly to pay industrial customers to cut their demand by x
| MW than to fire up x MW of ancillary generation. And as far as
| grid frequency/balance is concerned, has exactly the same
| effect.
|
| Often such customers will have flexible demand in the form of
| non-critical heating or cooling, pumps that only need to run
| some of the time, etc, which they are very happy to turn off
| temporarily in return for extra income.
|
| This is indeed an automatic process, triggered in near-real
| time in response to signals from the grid.
| jnsaff2 wrote:
| The grid frequency is a measure of energy balance in the grid.
| So anyone can measure anywhere in the frequency domain whether
| there is a surplus or deficit of generation. This is due to the
| fact that the grid itself can't store any energy, it has to be
| balanced all the time.
|
| Imagine the massive spinning generators as a big mass that slow
| down just a little bit when you switch on a light and then that
| generator has to add more steam (or open hydro valve or
| whatever).
|
| So anyone with an accurate enough measuring device can exactly
| monitor the state of the grid. We use this device [0] for
| example.
|
| There are generally frequency containment reserves (FCR) that
| consist of different ways of generation and have their
| different reaction times, power and energy capacities.
|
| Hydro for example can react in about 15 seconds, battery
| inverters in milliseconds. Gas turbines in minutes, coal fired
| plants in hours.
|
| You can also shed energy by switching off loads (Demand side
| response).
|
| The system operator is responsible for grid balancing in the
| short term, they have direct facilities under their control and
| they have contracts with generators and consumers. And there
| are markets to bid your generation and flexibility.
|
| The markets in the Nordics for example are:
|
| - FCR-N (Frequency containment Reserve - Normal operations)
|
| - between 49.90 - 49.99 and 50.01 - 50.10 (reaction time up to
| 20s)
|
| - FCR-D (Disturbance) - between 49.7-49.90 and 50.10 - 50.30
| (reaction time up to 2 seconds IIRC)
|
| - FFR (Fast Frequency response) - below 49.7 - reaction time
| 0.6s IIRC
|
| Once a day you bid your capacity for the next 24h (for each
| hour) and then you measure the grid frequency yourself and when
| you detect a deviation you activate your response. You get paid
| for availability and activation separately. There is a ton of
| qualification and logging you need to do to be able to
| participate but the activation message is the grid frequency
| itself, no further communication needed.
|
| Outside frequency regulation there is energy markets where
| generation and consumption is agreed 24h ahead.
|
| [0] https://www.gobmaier.de/
| bennofs wrote:
| > Imagine the massive spinning generators as a big mass that
| slow down just a little bit when you switch on a light and
| then that generator has to add more steam (or open hydro
| valve or whatever).
|
| I have always wondered, would that still hold true if the
| grid was fully solar-based? There would be no rotating mass
| in that case.
| jnsaff2 wrote:
| Yes indeed, inverter based generators (solar and batteries)
| don't have any inertia. But as long as the grid is still AC
| the frequency will be the same and the inverters would need
| to compensate internally. Especially with solar where a
| cloud going over a solar farm can easily knock off a few MW
| in seconds the volatility of the grid will increase and
| need for storage (batteries, hydro, etc) alongside Demand
| Side Response is getting much bigger.
| netflixandkill wrote:
| Yes, although a significant issue with that is there is no
| spinning mass to "borrow" inertia from, so while modern
| inverters at solar sites are good at shaping output phases,
| they have very little capability to absorb significant
| frequency deviations.
|
| Grid scale battery systems are often used for voltage or
| frequency stability as opposed to deep discharging as
| generation offsets, although that will change eventually if
| batteries get better enough or really cheap LNG stops being
| a thing.
| brandmeyer wrote:
| It does hold true for some systems. Wind turbine generator
| controls can provide virtual inertia over very short time
| scales (a second or few) by exchanging energy with the
| turbine rotor. You can also provide primary frequency
| reserve in the negative direction (load step-off) using
| exactly the same ramp control that steam plants use.
| Typical ramp rate is 100% of rated power for a 5% change in
| frequency.
|
| However, in order to provide primary frequency reserve in
| the other direction, you do need additional local storage.
| You don't need very much. Just 10% of rated power for 15
| minutes gets you to very deep renewable penetration.
|
| The trouble isn't with the technology, its with the
| economics. Once you set a sufficiently high price for
| frequency support and primary frequency reserve, suppliers
| will show up.
| liversage wrote:
| Something similar happened in 2018. However, it was not a
| technical problem but a conflict between the power grid operators
| in Serbia and Kosovo.
|
| https://www.dw.com/en/clocks-in-europe-are-running-late-beca...
|
| I believe that if you adjusted your clock during the conflict you
| had to adjust it again when it was resolved as the resolution was
| to increase the frequency for a period to reverse the loss of
| frequency.
| GekkePrutser wrote:
| Aha so this is what caused that big frequency drop people had
| already reported. Interesting!
| cpach wrote:
| Relevant Wikipedia article:
| https://en.wikipedia.org/wiki/Synchronous_grid_of_Continenta...
|
| Must admit I've never heard of this before :-)
| m463 wrote:
| Funny how the folks on this site will still wade into an
| article even with a completely unrecognizable (yet curious)
| title like this one.
| brohee wrote:
| Infosec slant: such investigations are made way easier by precise
| timestamping (everything happens in a few milliseconds), but the
| source of truth (GPS or other GNSS) is usually pretty easily
| spoofable if you only intend to move the time a few milliseconds.
| Galileo has a project addressing this
| (https://ec.europa.eu/transparency/regexpert/?do=groupDetail....)
| but AFAIK it's not in the signal yet. And once it is, it will
| take years for the devices doing the satellite time to PTP to be
| replaced/updated.
| traceroute66 wrote:
| Surely this is only true to a minimal extent in world where you
| can already buy timeservers that support multiple independent
| time sources out of the box (multiple satellite Galileo,GPS
| etc. + terrestrial radio e.g. DCF77).
|
| IIRC if you're dead serious and money is no object, all the
| major national time labs also allow you to run a private leased
| line to their facility for direct checks.
| brohee wrote:
| As of now all GNSS constellation are somewhat spoofable,
| especially if you only want to drift a clock a few
| milliseconds late... And a lot of timeservers are still GPS
| only so the attack is pretty easy to perform.
|
| The private line idea is maybe doable (but which protocol?
| NTP doesn't offer the needed precision), but as all
| substations would need one, my guess is that eventually money
| would be an object...
| michaelt wrote:
| _> (but which protocol? NTP doesn 't offer the needed
| precision)_
|
| You might enjoy reading the documentation for NPLTime [1]
| which uses PTP over telecom fibre networks.
|
| Of course, their target market is banks with record keeping
| requirements so it probably costs a fortune.
|
| [1] https://www.npl.co.uk/npltime
| jasonjayr wrote:
| Previously, from the 8th:
| https://news.ycombinator.com/item?id=25685646
| contravariant wrote:
| Seems like an excellent example that preventing a single point of
| failure means nothing if your system doesn't have the extra
| capacity to handle a single failure.
| nabla9 wrote:
| There was multiple failures, not single.
|
| The grid was separated but it didn't cause more power outages.
| londons_explore wrote:
| If you design an electricity grid to never partition, then you
| need to keep a substantial headroom of transmission equipment
| unused to prevent cascading failures leading to a partition in
| case of failure of just one or two sites.
|
| Instead, an electricity grid should be able to survive any
| partition like this while still keeping all frequencies within
| the nominal range. The total cost of such a system is lower in
| most cases (you need more idling generation capacity or droppable
| load, but less transmission capacity)
|
| The EU system here failed to do either here.
| frede wrote:
| The system survived the partitions, there was no widespread
| blackout. Further, the system is not organized by the EU, but
| the ENTSO-E and contains e.g. countries from North Afrika.
| cbmuser wrote:
| There was no blackout _yet_, but it was very close.
|
| According to the German Bundesnetzagentur (the equivalent of
| the FTC/EIA), the number of times where they have to
| intervene with the grid due to grid instability is constantly
| rising due to Germany shutting down nuclear and coal plants.
|
| > https://www.bundesnetzagentur.de/DE/Sachgebiete/Elektrizita
| e...
| imtringued wrote:
| According to this chart there has been an insignificant
| reduction in installed capacity.
|
| https://energy-
| charts.info/charts/installed_power/chart.htm?...
|
| Nuclear power went from 20GW to 10GW. Hard coal went from
| 28GW to 22GW.
|
| Ok, but gas went up from 23GW to 29GW. Brown coal stayed
| the same.
|
| Renewables went up by by 50GW for PV and 50GW for wind.
| Consider that wind often hits a 50% capacity factor. That
| is 25GW in additional power just from wind alone.
|
| Some of those plants may not be running continuously but
| they are still useful for emergency responses.
| Dumbdo wrote:
| > There was no blackout _yet_, but it was very close.
|
| Where do you get that from? None of the sources reported a
| close blackout, as far as I understood it there was a lot
| of emergency capacity left. We weren't even in the
| emergency frequency range, as the other commenter pointed
| out.
|
| Even the linked article just states that those
| interventions got more often after shutting down
| coal+nuclear, but it's not critical, it _only_ costs money
| to compensate the operators:
| https://de.wikipedia.org/wiki/Redispatch_(Stromnetz)
|
| It's probably much less money than all the nuclear
| subsidies.
| phicoh wrote:
| It is a choice, spend a fortune on nuclear power that
| nobody wants in their own backyard, or deal with a less
| stable grid due to solar and wind energy.
| qayxc wrote:
| Sigh. It's not a dichotomy at all.
|
| It's perfectly possible to have a stable grid even with
| solar and wind.
|
| The problem is that neither nuclear nor coal power
| stations are load following and "base load" has lowered
| over the years (industry has moved to Asia, devices
| became more efficient, etc.).
|
| Stand-by power (like natural gas powered generators)
| hasn't been built up the way the way it should have been.
| Same goes for smart grid technologies and buffer storage;
| not to mention the maniacs (especially in South Germany)
| who basically protest _everything_ - from nuclear power,
| to wind power, to required infrastructure like north-to-
| south high-voltage transmission lines.
|
| It's way too oversimplified to reduce the issue to just
| wind and solar.
| jabiko wrote:
| I'm not sure this counts as a failure.
|
| The load shedding mechanisms worked, supportive power
| generation was automatically activated and there was no
| widespread blackout.
|
| You are right that it appears like there was insufficient
| capacity at the north-west/south-east separation point and I
| guess that is going to be investigated but apart from that
| everything looks like it worked.
| zaarn wrote:
| The frequencies were in nominal range. The lowest was around
| 49.7, the highest about 50.6, both of which are within the
| allowed range of frequency (47.5 - 52.5 is the absolute
| emergency range, 49-51 is the nominal range, before you start
| capping power to or from customers).
|
| Romania had a power blackout for a bit, but everything worked
| as intended and the romanian grid blacking out didn't pull in
| the rest of the european grid.
|
| A partition between power grid is acceptable to preserve the
| largest amount of the grid remaining functional. Marrying the
| partitions together is bothersome but not something that takes
| forever (took 1 hour in this case).
|
| While 49.7 is very low, most of your devices will not notice
| and will be fine. Most industrial equipment is largely already
| coded to handle frequency shifts in favor of keeping the grid
| stable.
| reitanqild wrote:
| What puzzles me is why everyone talks about _clocks_..!
|
| Clock synchronisation is a nice side effect, but what amazes me
| is how it is possible to keep this thing swinging somewhat
| synchronously year after year, and how huge chunks of it doesn't
| crash and burn when events like this happens.
|
| (I have worked as a consultant for a power supplier, I was more
| puzzled afterwards : )
| littlestymaar wrote:
| > what amazes me is how it is possible to keep this thing
| swinging somewhat synchronously year after year
|
| There's nothing to do to keep them in sync: every single[1]
| alternator connected to the electric grid is rotating at the
| same speed, which is driven by the frequency of the
| electricity. This is a physical effect.
|
| The big challenge isn't to keep things in sync, it's to keep
| the supply equals to the demand. (when we don't, the frequency
| goes up or down depending on which is higher than the other)
|
| [1]: in thermal stations only, wind turbines are not directly
| connected to the grid because their rotation speed depends on
| the wind...
| reitanqild wrote:
| > There's nothing to do to keep them in sync: every single[1]
| alternator connected to the electric grid is rotating at the
| same speed, which is driven by the frequency of the
| electricity. This is a physical effect.
|
| You either know a lot less than me or you know more and
| understand it better. I honestly can't tell : )
|
| It feeks like my brain collapses just from starting to think
| about thousands of kilometers of grid, thousands of power
| stations, millions of consumers etc. (Not that the amount of
| them matters, just the supply or demand they deliver/drive.)
|
| In the interest of learning, here is my model that I map the
| things I do understand to:
|
| The way I (as a hardware/software engineer who started in
| electronics and had a brief course on power electrics) reason
| about it is torque, as if they are kind of sharing a common
| shaft and applying torque to it while consumers are braking
| it.
|
| This simplified mental model would explain - kind of - how it
| can stay in sync, only in reality we are talking not a linear
| axle or shaft but this continent-wide grid where gigawatts of
| supply and demand can occur within minutes or even less and
| the phase differs by quite a lot over the span of the
| continent. (In my mental model this is the axle twisting.)
|
| Also at 50Hz the wavelength of light in vacuum should be
| around 6000km if I typed correctly and DDG understood
| correctly. A rule of thumb we learned (in high frequency
| electronics back in electronics engineering) was that once
| you cross a tenth of that the normal rules doesn't quite
| apply. If this can be applied to power grids (an I think it
| can) it becomes even more complex I guess. (The
| simplification we can apply in "small" circuits is that we
| can pretend evey point in the circuit is at the same point of
| the phase at the same time.)
|
| Keep in mind everyone: these are just my models. I'll be
| delighted if littlesymaar (or someone else) knows this
| extremely well and manages to enlighten me because it would
| be fun to really "get" it.
|
| Edits: A lot.
|
| Also: Just operating one power plant can be complex: I
| remember one presentation from former students or something
| about how important it was in Eastern Europe back then to be
| ready to cut immediately if neighbouring plants failed or cut
| so that your plant wouldn't suddenly oversupply and burn out.
| nine_k wrote:
| I think the idea of a common shaft, only provided by
| electricity, is a good approximation.
|
| But the shaft of such length is not very "rigid", and the
| task is to keep it from wringing and breaking by keeping
| all parts of it rotating at the same speed.
|
| (As a side note: have you heard of selsyns?)
| brandmeyer wrote:
| Something that might help: It isn't one axle twisting. Any
| one source or sink on the grid can model themselves as a
| single shaft coupled to the rest of the grid, but for
| conceptualizing it as a whole you really do have to think
| of it as a system of coupled machines.
|
| One thing that might help with the stability intuition: The
| generators themselves are synchronous machines, but they
| have parasitic induction machines deliberately installed in
| the form of damper bars. Those damper bars mean that the
| vibrating mode between the generator rotor and the stator
| field is well-damped. Similarly, the vast majority of total
| load is in the form of induction motors which naturally
| have a damped response between the motor rotor and stator
| field. So resonating patterns and shocks are quite
| difficult to set up. Even sharp step inputs are attenuated
| to be not-sharp over short distances.
|
| In the US, one common test for grid step response is
| dropping an entire nuclear power plant. Not one reactor:
| the entire site. So several GW of electric supply is
| dropped instantaneously. The limit typically isn't any kind
| of oscillation, its the ability of primary frequency
| reserve to pick up the slack before you start triggering
| under-frequency trips.
| LargoLasskhyfv wrote:
| Tell us _more_ about that :)
| reitanqild wrote:
| I cannot really but I have put my lack of knowledge on public
| display here for someone else to help me and you :
| https://news.ycombinator.com/item?id=25917037
|
| : )
| LargoLasskhyfv wrote:
| Thanks. I've already read that ;) But let me say this.
| About 10 to 15 years ago I've been more interested in
| transmission lines because of "Energiewende" and such, came
| across HVDC, how that would enable smart grids, possibly
| protection against solar/geomagnetic storms because of
| faster switching times, and so on. I looked into how they
| built those HVDC-lines in China, how that is not new at
| all, but eased by modern solid-state power semiconductors,
| and so on. And looked further into patents, modulation
| schemes, even many 'papers'(pdf) and also very technical
| books(skimmed those only).
|
| Anyway, what I learned was that the grid has _many_ very
| nonlinear phenomena which are extremely hard to model and
| predict, because of the dynamics. Much more complicated
| than the simplistic answers some here have given you.
| So...relax?
|
| :-)
| LargoLasskhyfv wrote:
| You know what I'm missing? The almost realtime map from ucte.org
| which updated every 3 to 5 seconds on my Pentium3 933 with only
| 512MB Ram in the browser.
|
| I think it needed some plugin, either Java or Flash, but you
| could zoom in or out, either to the whole of Europe, or down to
| the substations in the cities and towns.
|
| It was like google maps or similar. AND it had _all_ the
| transmission lines, power plants, and substations.
|
| And color coded lines, with KW/MW/GW and arrows indicating the
| direction of energy flow on them.
|
| Anybody could view it without having an account there. At least I
| did, from time to time.
|
| This way of viewing it in realtime is now gone, or at least not
| accessible to the general public anymore.
|
| Does anybody know some equivalent?
|
| Sites with bargraphs and charts need not apply.
| Reason077 wrote:
| ENTSO-E is the successor organisation to UCTE [1], with its
| functions transferred to ENTSO-E in 2009. So if anyone has the
| data, it would be them. Interesting that the ucte.org website
| still seems to be online and frozen in time!
|
| [1] https://www.entsoe.eu/news-events/former-
| associations/#union...
| andreasley wrote:
| While ENTSO-E does have a map [1], it's not as nice as the
| one described above.
|
| [1] https://www.entsoe.eu/data/map/
| LargoLasskhyfv wrote:
| Yes, does not compare, unfortunately.
| noobermin wrote:
| I hate to commit red-herring but this is another example
| of how computing is worse today in some ways.
| [deleted]
| LargoLasskhyfv wrote:
| Yeah, I noticed that some years ago. They don't have that
| offer anymore. Interestingly, looking at the article, the
| cutouts are in the exact style of that former realtime map.
|
| But static. Not living. That was once there, and available to
| the general public. Personally, I view that as artificial
| scarcity of information, regarding energy politics.
| 'Smokescreening' so to speak.
| EE84M3i wrote:
| Is it possible it's no longer available for security
| reasons?
| LargoLasskhyfv wrote:
| I don't know. I've thought about that. OTOH if some
| terrorist would like to know the choke points of the
| grid, he could deduce that from openstreetmaps also,
| where the transmission lines and substations are
| available for viewing.
| intrepidhero wrote:
| The physical layout of the transmission system is
| basically impossible to obscure, but does not necessarily
| give the attacker insight into power flows. Having access
| to real time power flow data would enable an attacker to
| design a cascading failure scenario, making an attack
| MUCH more effective. The last component would be knowing
| operational response procedures. Which seem to be fairly
| transparent in Europe? If so I'm surprised more care
| isn't taken to secure them.
| WanderPanda wrote:
| It is probably right, but I have to say that I hate that
| kind of security through obscurity
| LargoLasskhyfv wrote:
| Especially when there is this https://de.wikipedia.org/wi
| ki/Stromausfall_in_Europa_im_Nove... which was caused by
| switching this off, https://de.wikipedia.org/wiki/380-kV-
| Ems-Freileitungskreuzun... which is rather similar to
| https://de.wikipedia.org/wiki/Elbekreuzung_2 :-)
|
| Even if there are surveillance cameras on those masts,
| there aren't on the masts leading to it. So you could
| ride your bicycle there, have some fun with thermite, and
| finally enjoy the stars again!1!!
|
| /me giggles (j/k)
| javajosh wrote:
| Yes, and honestly someone determined to do damage like
| that would be the sort to be patient and methodical
| enough to find targets with or without the map. But I do
| understand the instinct to want to at least increase the
| barrier to destruction, the problem is that it ALSO
| increases the barrier to understanding (and so protection
| and enhancement). So, an understandable but bad trade
| off, IMHO.
| LargoLasskhyfv wrote:
| I didn't see it from that point of view. It was just
| interesting to watch for me, out of the corner of my
| eyes, while doing other stuff on other systems and
| screens. I did that somewhere between 2005 and 2008,
| whenever I felt like it :-) With a focus on Germany in
| general, and my town especially. So I had it mostly
| zoomed just so that Germany was in view, with small parts
| of neighbouring countries visible. We didn't have that
| much solar and wind at the times. But sometimes one could
| see the direction of flow switch. From/to France for
| instance, or Denmark. And I think I've seen that to/from
| Poland and Czech also.
|
| Anyway, you could get a feeling for how things were
| depending on time of year/day, weather, and so on.
| Intuitevely, because presented spatially and realtime.
|
| And you don't get that spatial intuitiveness from the
| substitutes with (often delayed) charts & graphs.
|
| Which makes it impossible to counter bullshit by
| politicians or other parties with vested interests when
| they are saying this and that, and you could have said:
| _Ahem, that is not entirely correct, because there and
| then it was like so, and not what you say!_
|
| And the loss of that ability is making me angry!
|
| edit: Regarding the 'intuitiveness' of spatial vs. bars &
| charts. Even when the possibility to filter for im/export
| between countries exists, it does not show over which
| lines it went. Which could be useful in discussions about
| extending/upgrading lines, or building new ones. It's
| just not there.
| layoutIfNeeded wrote:
| Someday someone will reimplement it in React, and you will only
| need an i9-9900k with 64Gb to run it somewhat smoothly.
| LargoLasskhyfv wrote:
| Where would someone get the realtime data? Technically it
| _has to_ exist, otherwise frequency regulation wouldn 't
| work. The fact that they don't show it in the way I
| described, shows that they don't want to anymore, because
| they don't need to because of different organizational
| structure, or the structure has been made that way for
| ideologicel reasons by politics, i.e. 'smokescreening'.
| rkangel wrote:
| Is it possible that not making that level of data available is
| purposeful from a security point of view?
|
| Western European countries (among others) worry about threats
| to their "Critical National Infrastructure", whether in person
| (terrorist with a bomb) or as a cyber attack. Providing a big
| map with all transmission lines, power plants and substations
| seems like it would be a big help to an unsophisticated
| terrorist, showing them what to blow up.
| LargoLasskhyfv wrote:
| I don't think so, because you can see that on openstreetmap.
| I mean the transmission lines and substations.
| Havoc wrote:
| Like this:
|
| https://www.electricitymap.org/map
| LargoLasskhyfv wrote:
| While that is looking nice, (and I don't know how 'realtime'
| it is) it lacks the structure of the transmission nets, and
| the zoomability down to substation level in the towns/cities.
| I can't remember exactly anymore, it didn't show every
| transformer in town, but the places where the high voltage
| overland transmission lines entered into town, and were
| transformed down to more managable levels were there. I think
| down to 10.000/50.000 Volts. That was different regionally.
| For instance Portugal vs. Germany.
| theandrewbailey wrote:
| That's a lost art nowadays, doing all that on a Pentium 3.
| Today, you'd need about 512 GB of RAM and a supercomputer to do
| the same.
|
| \s
| LargoLasskhyfv wrote:
| Hrrm. I did that under some Linux and KDE 3.x, maybe even
| with the KDE Browser called Konqeror. That was usable at the
| times :-) 2005 to 2008 that must have been.
| pmayrgundter wrote:
| Did it look like this?
|
| https://www.researchgate.net/figure/Energy-trade-change-in-t...
|
| Seems like they're referring to it but also the comments
| suggest the data was from simulation of optimal market
| exchange, not actual electrical flows
| LargoLasskhyfv wrote:
| Nope. That is abstract. It looked exactly like the 2 blurred
| cutouts from the Entsoe article, where they put in the
| probable causes textmarker style. Interestingly it is hard to
| find screenshots of good quality or at all. Seems to have
| been a very special interest of mine?
| [deleted]
| AnssiH wrote:
| AFAIK the continental synchronous area frequency is long-term-
| synchronized to atomic time (i.e. the cumulative grid time must
| stay within X seconds of the reference clock).
|
| Looking at the (partial) graph suggests that the south-east part
| ran faster for the entire duration of the disconnection.
|
| Does this mean grid-synced clocks in the south-east part are now
| permanently ahead of the atomic reference, or are they planning a
| mitigation (which I assume would have to mean disconnecting again
| and running the SE part slower for a bit)?
| gspr wrote:
| > Does this mean grid-synced clocks in the south-east part are
| now permanently ahead of the atomic reference, or are they
| planning a mitigation (which I assume would have to mean
| disconnecting again and running the SE part slower for a bit)?
|
| That's the standard procedure. Maintaining an exact frequency
| can be hard, but _counting cycles_ is easy. So the frequency
| will slew to slowly compensate back.
|
| Edit: Here's a Tom Scott video on a UK-Continental divergence
| that happened a while back:
| https://www.youtube.com/watch?v=bij-JjzCa7o
| garaetjjte wrote:
| UK is connected through DC lines, so frequency is
| independent. In this case they would have to separate the
| grid again to be able to correct this.
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