Author Topic: Electricity generation and storage.  (Read 1086 times)

Electricity generation and storage.
« on: August 11, 2019, 07:49:25 am »
I was listening to a new article on Radio 5 last evening about the great power cut of Friday 9th August when two power generating stations failed within 2 minutes. One guest was bemoaning the use of "inflexible renewable wind power" so much so I thought he was going to demand the re-opening of the pits and coal powered stations (according to Grid watch, Coal generated no power at 9.30pm last night, while wind was up there at 35% of the total produced).

Something was then said which interested me about the fact that there is a company out there who are currently building a 2GW storage facility and that a lot of storage is currently available at home in the batteries of mobile cars.

This latter point surprised me as the Cowboys who fitted my EV home charge point didn't mention that to me, or show me how to do so in emergencies. So, did I miss hear? Also, I have 4kw power solar panels on my roof. If we get a power cut on a summer's day, will this power my house on minimal or indeed normal usage until the mains are restored? All the power cuts we have had recently have been at night.

Finally, does anyone have a power wall? I was wondering if it was worth getting one before our stupid Government increases VAT on them to 20%. Why would anyone with half a brain do that?!

Sorry if these are stupid questions but in my half asleep mind I may have misunderstood some simple points the guest made.

Cats to the left of me, cats to the right of me, cats sitting on my keyboard making far more sense than I do.

Re: Electricity generation and storage.
« Reply #1 on: August 11, 2019, 08:05:43 am »
Vehicle-to-grid is a mostly hypothetical technology that *could* be a big deal in future but pretty much doesn't exist now, and certainly not for home users.Tech pundits have a habit of mixing up reality with things they want to exist because it makes for interesting soundbites.

AIUI the power cut was down to the wind farm (and a fossil fuel station) tripping out for some reason, not because the wind suddenly stopped blowing. Happens with fossil fuel stations all the time.

Re: Electricity generation and storage.
« Reply #2 on: August 11, 2019, 08:14:46 am »
Cheers, I thought it would be something like that with home storage. And yes, given the size of the UK including it's sea bed, it is always likely that the wind will be blowing somewhere!  :thumbsup:
Cats to the left of me, cats to the right of me, cats sitting on my keyboard making far more sense than I do.

Kim

  • Timelord
Re: Electricity generation and storage.
« Reply #3 on: August 11, 2019, 08:27:09 am »
Also, I have 4kw power solar panels on my roof. If we get a power cut on a summer's day, will this power my house on minimal or indeed normal usage until the mains are restored?

Only if you have an island-capable inverter and appropriate changeover isolation, which you probably don't because you're asking this question.

The usual ones for domestic installations switch off automatically if there isn't mains power to sync to, so they don't back-feed the local grid and electrocute linesmen.
To ride the Windcheetah, first, you must embrace the cantilever...

Re: Electricity generation and storage.
« Reply #4 on: August 11, 2019, 08:49:00 am »
From what I've read, the windfarm was out for 15 minutes (ditto the gas generator). Could have been a coal station - it was nothing about it being wind specifically; the moaners are conveniently ignoring the gas station dropping out.

The problem was a cascade when the frequency started to drop. Automatic grid systems meant that the way to stabilize the national grid was to shut off portions.

Having a powerwall would be ideal, but sounds expensive.
<i>Marmite slave</i>

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: Electricity generation and storage.
« Reply #5 on: August 11, 2019, 11:40:58 am »
For a once every few years event, I doubt it's worth doing anything like a powerwall for home use, unless you have vital equipment like home dialysis. In parts of the world where power cuts are a daily expectation, they'll be out of reach for most people but home solar coupled with storage for an hour or so should be literally an air cleaner, replacing the portable generators chained outside small shops.
sideways bounding monkey lounging under fruit tree

quixoticgeek

  • Mostly Harmless
Re: Electricity generation and storage.
« Reply #6 on: August 11, 2019, 12:28:06 pm »
I was listening to a new article on Radio 5 last evening about the great power cut of Friday 9th August when two power generating stations failed within 2 minutes. One guest was bemoaning the use of "inflexible renewable wind power" so much so I thought he was going to demand the re-opening of the pits and coal powered stations (according to Grid watch, Coal generated no power at 9.30pm last night, while wind was up there at 35% of the total produced).

There is truth in the claim that renewables and micro generation make the grid harder to manage. But the reality is, NG are doing great at managing that. Wind generation didn't cause the issue on Friday.

Two large power plants disconnected in quick succession. One was gas, one was wind, but the second could equally have been coal, or nuclear, or gas. The thing with the wind one disconnecting is that the turbines were still spinning, there just was no connection to the grid. Which is an interesting failure mode.

Quote
Something was then said which interested me about the fact that there is a company out there who are currently building a 2GW storage facility and that a lot of storage is currently available at home in the batteries of mobile cars.

Grid scale storage is a thing. The UK has had that for decades. We call it pump hydro. It's a battery in so far as it stores energy, tho it stores it in the form of water at height, rather than lithium ions in a chemical matrix. But it's still energy storage.

Grid scale storage came to many peoples attention due to a publicity stunt by Elon Musk in Australia. He pledged to build what was then a massive (possibly worlds largest[citation needed]) 129MWh battery in southern Australia, and to do so in an insanely short time scale, or it would be free.

That 2GW storage bank seems a interesting claim. That's the same as 20000 Tesla P100 vehicles. That's a lot of battery. At least, if they mean 2GWh, not 2GW. Which is where things start to get a bit of a murky mess. I can build a unit with a 5KW inverter capable of pumping 5KW into my home power, but as it's connected to an old 12AH battery I have under the desk (from a UPS), it would only supply that 5KW for a matter of seconds. So it could be that they have a single battery with a capacity of 2GWh, or it could be a 100MWh battery, with an inverter capable of pumping it into the grid at 2GW.

Now given the UK already has a 50MW battery in hertfordshire (no data on if that's 50MW or 50MWh grumble grumble), adding a 2GWh storage seems... far fetched...

Quote
This latter point surprised me as the Cowboys who fitted my EV home charge point didn't mention that to me, or show me how to do so in emergencies. So, did I miss hear? Also, I have 4kw power solar panels on my roof. If we get a power cut on a summer's day, will this power my house on minimal or indeed normal usage until the mains are restored? All the power cuts we have had recently have been at night.

Finally, does anyone have a power wall? I was wondering if it was worth getting one before our stupid Government increases VAT on them to 20%. Why would anyone with half a brain do that?!

Sorry if these are stupid questions but in my half asleep mind I may have misunderstood some simple points the guest made.

So, vehicle-to-grid, v2g. It's been coming Real Soon Now™ for a while now. In theory it's a fantastic idea, it allows for proper demand side management, it allows you to make use of really cheap electricity etc... *BUT* It's not there yet.

There is a company in the UK that has demonstrated it as working for Nissan Leaf vehicles. They had a nice demo of vehicle to tea at Fully Charged Live. But as far as I am aware, there's not yet a proper standard for it, and it's not been fully realised as available.

The thing is, when it is, it'll be FANTASTIC. You can drive to work, charge up on the work charger in the work car park, drive home, and with the range left in the battery, cook dinner, and power your house, then drive back to work the following day and charge up... Or you can charge at 3am when electricity is practically free, and then even out the spike at 1800 when everyone turns their oven on...

How does it work? well you basically need to trick the car into connecting the internal battery to the pins of the charging cable, and the you need to work out how to turn the DC in the car, into 230v AC for your house. It's not simple. Take a look at your charging cable. Two of those pins carry power (assuming chadamo), the rest carry data signals to allow the car to talk to the charger. If you have CCS, or CCS2, then it gets even more complex as you have a mix of AC pins, DC pins, and data pins. It's not quite as simple as siphoning the petrol out the tank of the old dinosaur burner to power your generator.

As to the solar, if you have a simple grid tie inverter, then you're unlikely to be able to disconnect from the mains and power the house on a sunny day directly. Apart from anything else, a single cloud could drop production, causing a brownout which could really mess with devices plugged in. For this to work, you really want something battery like to buffer in vs out. The way you describe the cowboys who have done your installs suggests this wasn't even a consideration. Fitting a battery, be it a power wall or some other solution may require a new inverter.

On to the power wall. I've tried to do the maths on it. I can't find a way to make it cost effective on it's own, but then I don't have solar. If you do have solar, then the maths is a bit better, but there may be other products that are more cost effective than a tesla branded one. If you're only looking at it to cover the occasional power cut, then actually the most environmentally friendly approach is probably a second hand generator off ebay, and run it on diesel you keep for emergencies. Nothing new has been created, and the amount you will actually burn, will be negligible (plant a tree to offset each power cut).

Electricity, the Grid, and vehicles are going to change dramatically in the next few years, it's gonna be interesting to watch!

J

PS, Grid watch claims no coal was burning on Friday. This is actually wrong. No DOMESTIC coal generation. The UK has power interconnects (at least until the end of October), with a couple of it's neighbours, all of which (apart from France) have substantial coal generation as part of their mix. Unfortunately due to the way power from these interconnects is provided we have no means to see if the power coming in from Belgium is coal or gas or nuclear or whatever. Meaning that we can claim no domestic coal generation, we can't be 100% certain the UK used no coal power at all.
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Re: Electricity generation and storage.
« Reply #7 on: August 11, 2019, 02:44:05 pm »
Thanks all for your wonderfully detailed and interesting replies.

You know what I love about this forum? Its the way you ask a question and without doubt someone will be along who knows the answer and is happy to share it with you.  :thumbsup: :thumbsup: :thumbsup: :thumbsup: :thumbsup: :thumbsup:
Cats to the left of me, cats to the right of me, cats sitting on my keyboard making far more sense than I do.

Re: Electricity generation and storage.
« Reply #8 on: August 12, 2019, 06:43:34 am »
Some years back there was a typically brilliant feature on radio 4 about storage of renewable energy which covered loads from the obvious batteries to compressed air and IIRC even hydrogen.

Incidentally was it the fact that the wind turbines weren't connected to the grid that made them create too much wind over the weekend?

fruitcake

  • some kind of fruitcake
    • Bailey
Re: Electricity generation and storage.
« Reply #9 on: August 14, 2019, 09:49:18 am »
What struck me as remarkable about the recent outage was just how vulnerable the railway is, and that a 90-minute cut led to 8 hour delays, presumably because immobile trains ended up in the way. The railway is surely a good candidate for battery back up, even if emergency power were to last only minutes. 

On the question of resilience at home, I think if I were setting up a house, I'd install as much storage as possible using current tech. That would mean battery-powered lighting on stairs and corridors, hot water storage, storage heaters* and super insulation. I'd also choose DC powered ICT equipment.

*probably not as the only space-heating

Re: Electricity generation and storage.
« Reply #10 on: August 14, 2019, 10:01:51 am »
There was quite a good blog post from Flexitricity.   Text here :-

Flexitricity was having a quiet afternoon, with most of our customers getting on with the day job, and just a few megawatts of Short Term Operating Reserve running at the time. We were also charging some battery capacity under Balancing Mechanism instruction. National electricity demand was a modest 28GW when, for as-yet-unannounced and probably mundane reasons, Little Barford power station tripped. It had been generating 664MW. Little Barford is a combined-cycle gas turbine (CCGT) of nineties vintage, snuggled next to the main east coast train line between London and Edinburgh. It’s owned by RWE.

At around the same time, Ørsted’s brand new Hornsea offshore wind farm also tripped. Ørsted’s data housekeeping is perhaps a little less neat than RWE’s, so it’s tricky to ascertain exactly how much was lost (apparently at least 800MW), or whether Little Barford or Hornsea went first. But the combined effect was certainly larger than the largest single-infeed loss that National Grid would have been planning for – presumably the French interconnector, which was importing around 1000MW at the time. At other times, they might have been watching Sizewell B, which can hit 1250MW, but our most modern nuke was running at reduced power at the time.

Mains frequency plummeted to around 49.1Hz, wobbled, then took the final drop to the red line of 48.8Hz. At this level, there is an obligation on Distribution Network Operators to shed around 5% of demand, automatically and quickly. They do this with low-frequency relays around their networks, all set up in advance. This happened as planned. Demand fell by about the right amount, and frequency stopped falling. As Duncan Burt, National Grid’s Director of Operations, put it on the news on Saturday morning, “the system worked”.

From that point of view, it worked very well indeed. Frequency didn’t take long to recover – just long enough for National Grid to flip our battery charging into discharging, helping to fill in the power gap – but it rose so fast from there that they had to flip us back into charging mode. It’s worth remembering that excessively high frequency can be just as bad as low. Both can lead to nationwide blackouts.
This is what Duncan didn’t say. If the 5% demand cut hadn’t been enough to stop frequency falling, more demand would be cut at different frequency levels until the power stations themselves gave up trying. That would have led quickly to a nationwide blackout, and the one circumstance that really keeps National Grid awake at night: a black start. About a million people were affected by the power cuts that did occur, but their best chance of getting power back quickly was to avoid losing it nationally. It’s relatively easy to reconnect customers to a stable system; it’s a whole lot harder to restart a system where absolutely everything is off.

There will certainly be investigations, and they will be detailed. One thing which will receive a lot of attention will be the report dealing with strikingly similar events on 27th May 2008, when frequency fell to exactly the same level of 48.8Hz, following the near-simultaneous trip of two power stations. On that day, it was coal (Longannet) and nuclear (Sizewell B), rather than gas and wind. But both days saw a noticeable wobble in frequency as it headed south. The 2008 conclusion was that falling frequency had destabilised a number of distribution-connected wind farms. This led, one way or another, to the current project to upgrade protection settings at distributed renewable generators. If the same thing happened this time, there will be questions about the speed of that project, and whether the networks are doing enough to engage with their embedded generator customers and get this done in a collaborative way.
But it’s likely that much of the investigation will focus on something else: affected customers. Industry insiders need to remind themselves often that customers are real, that electricity is very important to them, and that failing to supply it can be really, really bad.

Two subjects will get special attention. The first is Ipswich Hospital, where a back-up generator reportedly failed, although battery-based uninterruptible power supplies successfully supplied critical areas. The woeful reliability of Britain’s standby generator fleet is something that Flexitricity has blogged about in the past, and as always, our solution is a proper test-and-exercise regime tailored to national and local need for electricity. This is something that recently became quite difficult: DEFRA and the Environment Agency got their wires quite seriously crossed when implementing the European Medium Combustion Plant Directive, making good testing much harder.

The second is trains. Since the distribution networks have a free choice as to which circuits to trip at the 48.8Hz trigger level, did they really have to do it to the trains? The May 2008 event caused a similar level of power cuts, but had far less impact on rail transport. So was the loss of traction power a direct result of the low frequency trip, or an unexpected secondary consequence? Perhaps more importantly, where was the resilience in the signalling system? This is a much smaller load than traction, and should be amenable to high-specification backup at modest cost.
I would be interested to know if anyone was stuck just south of St Neots on the east coast main line. If they were, they’d have been looking right at one of the two main sources of Friday’s blackout blues. But power stations like Little Barford sit down all the time. It’s prosaic; it’s planned for; and filling gaps like that is what Flexitricity does every day. Understanding why this particular event got so bad so quickly will be the subject of much detailed technical analysis. The solution won’t be to build lots more gas power stations. It wasn’t for want of fossil-burners that so many people took so long to get home on Friday night.

On the subject of getting around, I found myself in the BBC’s Inverness studio at 10pm that night talking about the blackouts. I got there in a fully electric campervan, which I’d charged that day using 100% wind energy. And that worked absolutely fine.

simonp

  • Omnomnomnipotent.
Re: Electricity generation and storage.
« Reply #11 on: August 14, 2019, 10:04:36 am »
We have 8kW PV and a 7kW car charger. You can't connect this much PV to the grid without permission. We have looked into adding battery storage. The grid (local DNO) will not allow it in addition to what we already have connected, unless we switch to a three-phase supply. Well, they will allow 3.6kWh of storage, which is tiny.

To have more than this we'd have to install a three-phase connection, i.e. significant cost, and that would require replacing the existing solar inverters. If we'd designed that in from day 1 maybe it would have made sense, but not retrofitting in the short term due to throwing away perfectly good kit. Maybe, if one of the inverters failed in say 10 years then it would be something to look into.

The DNOs are being quite conservative about battery storage, from what I've read. In theory it could make the network more stable but they are treating batteries as additional generation capacity.


Re: Electricity generation and storage.
« Reply #12 on: August 14, 2019, 10:06:45 am »
As this all happened in the short-term and after gate closure, the wholesale market and balancing market didn't react, in fact it was very benign all day.   Grid pay the battery and frequency providers a standing charge and this is paid out of customers bills.   The only way to allow for a bigger gap would be to procure more capacity which would, it is estimated, cost an extra £2 per household.

But this was a 1 in 10 event and Grid managed.   Even though I sit on a power trading desk I was not aware of the problems but did wonder why all the traffic lights on the Old Kent Road were off on Friday evenings commute.   It was only when I turned the TV on that I heard more and I then spent the evening following the updates.

ian

  • fatuously disingenuous
    • The Suburban Survival Guide
Re: Electricity generation and storage.
« Reply #13 on: August 14, 2019, 10:36:42 am »
That's the thing though – redundancy costs money – significant capital investment to implement and easy to whittle away as it offers a quick cost-saving and there's no exec these days who doesn't get a bumper bonus based on that. And as it's redundancy, you only find out you need it when you do.

That said, it seems the NG did a reasonable job – very poor that fundamental services like hospitals didn't seem to have tested their procedures, and it seems when it comes down to redundancies, there's bugger all on the rail system (unless you count experience staff).

Compared to everywhere else I've lived, British electric is really very good, it's the most stable I've ever encountered.
!nataS pihsroW

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: Electricity generation and storage.
« Reply #14 on: August 14, 2019, 11:01:22 am »
Apparently the problem on the railway was largely down to one type of train which, for some reason, needed engineers to come out and reset them when the power came back on. Signalling also needs to reset, it all comes back on at red for obvious reasons.
sideways bounding monkey lounging under fruit tree

Re: Electricity generation and storage.
« Reply #15 on: August 14, 2019, 11:02:11 am »
Compared to everywhere else I've lived, British electric is really very good, it's the most stable I've ever encountered.
Erm, yes.

I grew up with blackouts being a regular thing (once we had mains power). Household always had a stock of candles and tilley lamps because it wasn't uncommon for power to go out for 3-4 hours. A monthly occurrence at least.

Frequency fluctuations are so crap in Oz, even now, that it is accepted that you pretty much *have* to plug computers into a surge-protected socket. 
<i>Marmite slave</i>

ian

  • fatuously disingenuous
    • The Suburban Survival Guide
Re: Electricity generation and storage.
« Reply #16 on: August 14, 2019, 11:15:17 am »
The US and Canada too (though the US was worse). We had the bonus brown-outs and electricity rationing when I lived in Connecticut* and generally the power goes out if the wind blows or it rains or it's a day with a letter in it.

Still, we do take these things for granted. Wandering around Malawi the other year I was surprised to see a couple of Scottish Power vans and digger laying power cables by the road (ok, dirt track). I asked if they were finally getting electricity (other than from a dirty generator), oh no, I was told, they've not built the power station yet. Seems the Scottish government were paying for the lines but the Chinese had got cold feet about the station. When I was in Addis Ababa last year the advice was to have multiple cash cards because it's a lottery whether or not an ATM will lose power mid-transaction and keep the card as a souvenir of the occasion.

*this was primarily down to Connecticut having to temporarily power down its nuclear reactors for safety issues and, well, anyone remember Enron – so basically the state couldn't afford to buy electricity from NY or neighbouring states.
!nataS pihsroW

simonp

  • Omnomnomnipotent.
Re: Electricity generation and storage.
« Reply #17 on: August 14, 2019, 11:17:02 am »
Local power cuts used to be much more common in the 1980s. I think we forget that things could be a lot worse.

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: Electricity generation and storage.
« Reply #18 on: August 14, 2019, 11:21:07 am »
I was going to say exactly the same. We had a one-week power cut in a cold snap (snow) in April about 1980 or 81.
sideways bounding monkey lounging under fruit tree

Wowbagger

  • Dez's butler
    • Musings of a Gentleman Cyclist
Re: Electricity generation and storage.
« Reply #19 on: August 14, 2019, 11:51:53 am »
I was, as you do, talking to a bloke in a pub last night. We were talking about EVs and the charging point outside our house. This bloke is an electrician and a member of the Green/XR tendency in Southend.

I mentioned to him that we had recently changed the charging point outside our house because Dez was in the process of buying a Tesla. He asked me if we had gone for one of the "smart" charge point which allow for our car's battery to be a backup source for the grid should it need to and I said that we didn't because I was unaware of the existence of such things. It seems that he has just had some training in the fitting of such charging points, so presumably they are an option.
Oh, Bach without any doubt. Bach every time for me.

simonp

  • Omnomnomnipotent.
Re: Electricity generation and storage.
« Reply #20 on: August 14, 2019, 12:03:30 pm »
Ours should be capable of being smart but it awaits firmware updates. I’m pretty sure the car will not play this game. Generation equipment has specific requirements in terms of safety e.g. there must be a physical disconnect from the grid in case of a grid fault (via relays). I don’t think we can just start exporting to the grid without DNO authorisation. And you can’t run off-grid in a power cut from the car battery without the grid disconnect relays between the charger and the grid whilst allowing power from the car to be diverted internally. It’s just not that trivial.

With the Tesla system the Tesla gateway provides the physical disconnect. It sits between the grid and everything else, so when the grid goes down it isolates everything. It then pretends to your solar panels that there is still a grid connection, so you can run off solar and charge or discharge the battery at the same time if there is an excess or shortfall.

Kim

  • Timelord
Re: Electricity generation and storage.
« Reply #21 on: August 14, 2019, 12:17:53 pm »
Apparently the problem on the railway was largely down to one type of train which, for some reason, needed engineers to come out and reset them when the power came back on. Signalling also needs to reset, it all comes back on at red for obvious reasons.

From the trainspotter discussions I've seen, it's a Known Issue™ with the Class 700 (as used by Thameslink).  Some sort of safety device locks out after three failed attempts to reset, which requires an engineer to sort out.  I assume they had someone on the design team whose previous work included the evil cell-balancing circuit on Makita power tool batteries.   >:(

It then doesn't take many stranded trains to multiply the chaos.

I'm not sure why trains need so many attempts at rebooting...
To ride the Windcheetah, first, you must embrace the cantilever...

Kim

  • Timelord
Re: Electricity generation and storage.
« Reply #22 on: August 14, 2019, 12:21:15 pm »
Local power cuts used to be much more common in the 1980s. I think we forget that things could be a lot worse.

OTOH, we had a lot less stuff relying on networks of computers that almost never get switched off at the same time.  In the 80s, when the power came back, stuff tended to work.  These days a major outage is a rare opportunity to find exciting new circular dependencies.
To ride the Windcheetah, first, you must embrace the cantilever...

quixoticgeek

  • Mostly Harmless
Re: Electricity generation and storage.
« Reply #23 on: August 14, 2019, 12:43:47 pm »
What struck me as remarkable about the recent outage was just how vulnerable the railway is, and that a 90-minute cut led to 8 hour delays, presumably because immobile trains ended up in the way. The railway is surely a good candidate for battery back up, even if emergency power were to last only minutes. 

On the question of resilience at home, I think if I were setting up a house, I'd install as much storage as possible using current tech. That would mean battery-powered lighting on stairs and corridors, hot water storage, storage heaters* and super insulation. I'd also choose DC powered ICT equipment.

*probably not as the only space-heating

Welcome to the wonderful world of failure modes.

In General, for a railway the best failure mode is for everything to just stop. This avoids things crashing into each other.

You then have the issue of trying to get everything back up and running. What train is where? what can move? Also consider that for the most part the trains can't easily go backwards. So if you've just left station A, and power dies, you're basically waiting to go forward to station B. Even if station a has clear track and is nearest.

Yes the railway was gummed up for hours, yes it wasn't pretty. But it was safe.

And for safety critical infrastructure, that is what you want. It's hard to explain to people, but can you imagine what would have happened if the power had cut and trains had crashed?

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: Electricity generation and storage.
« Reply #24 on: August 14, 2019, 01:09:39 pm »
Apparently the problem on the railway was largely down to one type of train which, for some reason, needed engineers to come out and reset them when the power came back on. Signalling also needs to reset, it all comes back on at red for obvious reasons.

From the trainspotter discussions I've seen, it's a Known Issue™ with the Class 700 (as used by Thameslink).  Some sort of safety device locks out after three failed attempts to reset, which requires an engineer to sort out.  I assume they had someone on the design team whose previous work included the evil cell-balancing circuit on Makita power tool batteries.   >:(

It then doesn't take many stranded trains to multiply the chaos.

I'm not sure why trains need so many attempts at rebooting...
Class 700 was the one I'd seen mentioned too, but I'm insufficiently trainspottery to have followed the details (or even to distinguish a Class 700 from any other EMU).

Also consider that for the most part the trains can't easily go backwards. So if you've just left station A, and power dies, you're basically waiting to go forward to station B. Even if station a has clear track and is nearest.
I am on the other hand sufficiently trainspottery to have been informed that reversing is allowed if any part of the train is still alongside the platform. Admittedly that's not of great use in this situation. (I also remember being on a train when the driver missed the braking point and overshot the station by a couple of hundred metres. He just reversed into the station. Good job it wasn't a terminus! But that was the 1980s... )
sideways bounding monkey lounging under fruit tree