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Spain is about to face the challenge of a "black start"

arstechnica.com

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Re: Spain is about to face the challenge of a "black start"

#91

Post by pas »

pbmonster wrote: post #73
flysand7 wrote: post #53

Oh man, this reminds me of factorio. When you miscalculate your power needs and your generators eat up the fuel that isn't being produced enough. I've had to make a bootstrapping mechanisms and power switches for some of my powerplants to ensure I can get it back up in case it goes down and I can then re-enable my factory bit by bit.

Unfortunately, you can't simply hand-feed 100 coal into all the Spanish thermal plants and then plop down two more to be on the safe side until you've fixed supply...

but sorta you can, that's not the hard part

it's that in Factorio there are no problems with phase synchronization, and the devices, consumers, producers, so the machines don't get damaged from a lot of abrupt starting/stopping.

still, it's strange that operators and grid controllers have to do the restart manually.

Re: Spain is about to face the challenge of a "black start"

#92

Post by myself248 »

AStonesThrow wrote: post #43
showsover wrote: post #30

Earlier quoted context omitted.

I was referring to the fact that generally people prefer cold beer, not room temp beer.

> generally people prefer cold beer Do they? But why? Why would they? Are they simply accustomed to tasting it that way? I should say "not tasting it" because chilling a beverage basically kills its flavours, and they never make it to your tongue correctly. I would say that many people would be surprised and amazed if they tasted such things as Pepsi without ice, and without coming right out of the fridge. Unfortunat…

I've always theorized that, in prehistory, the only source of cold water would be recent snowmelt; streams that came fairly directly from a probably-clean source. Warm water could have all sorts of things growing in it. So our ancestors who found cool water to be particularly refreshing and sought it out might have suffered less from waterborne illness.

Re: Spain is about to face the challenge of a "black start"

#93

Post by pas »

BiteCode_dev wrote: post #29
jerven wrote: post #21

Earlier quoted context omitted.

Yes, in theory, but your process control would be terrible, thus your product would also be terrible. Unless you invent something very clever.

But that makes them superb heat battery, which is under used at the moment to store energy.

because of the Carnot cycle, no? it just doesn't make much sense to store energy as heat

Re: Spain is about to face the challenge of a "black start"

#94

Post by justlikereddit »

Tade0 wrote: post #86
abe_m wrote: post #75

Earlier quoted context omitted.

At the time I'm writing this, there appears to be about equal (hydro + gas) = (solar + wind). It appears they are running a significant portion of the grid with high inertia generators. In a control system when you have an actuator that is much more responsive than the load, you can get into instable operating regimes where. On a small scale, when you are setting up servo motors, there is an inertia matching ratio fo…

Again, this appears to be a problem of coordination. An inverter doesn't have to: -react immediately -use its full capacity all the time

You have a fundamental misunderstanding of both how a grid in blackout mode appears to a lonely inverter and what means of coordinating inverters that are available to said inverter.

Imagine you're trying to coordinate a choir of ten million singers that are scattered across a radius of a thousand kilometer, that all sing into their individual Ham radio. And you need it to come out in a perfect unison that sounds good for those who tune into the mixed broadcast.

"A problem of coordination" is perhaps correct, but it neglects the difficulties involved

Re: Spain is about to face the challenge of a "black start"

#95

Post by myself248 »

zeristor wrote: post #46

I am no expert, however with solar power and more grid batteries (I don’t think Spain has many grid batteries) wouldn’t it be possible to charge the batteries and use that to drive a ‘black start’. Sounds simple, and I appreciate from experience a huge amount of prep and validation needs to be done in the background.

At an extremely abstract level, it is conceptually simple, but most inverters are designed with safeguards to prevent exactly this. They only produce power when the grid is up, and in phase with it.

Because if not sequenced and interlocked, islanding behavior can result in back-powering parts of the grid that are supposed to be disconnected and down for maintenance, or creation of desynchronized islands that then cause more damage when reconnected.

This is absolutely a problem that operators need to solve. Radio synchronization is possible, neighborhood islanding could be beneficial, etc. There are entire village-wide micro-grids in remote places where everyone's inverters do perform these functions, it just hasn't been embraced in monopoly environments yet.

For instance, relays that close isolated parts back onto the main network would need to be phase-aware, to only reconnect if it's safe to do so. You could mandate that all island-mode inverters center themselves around 50.1 or 60.1Hz in the absence of outside influence so there's certain to be phasing opportunities. Distribution networks would need more switches to provide positive isolation during maintenance. And all of these things would need huge amounts of interoperability testing. It's possible, but it has a cost.

Re: Spain is about to face the challenge of a "black start"

#96

Post by richij »

khafra wrote: post #80
abe_m wrote: post #75

Earlier quoted context omitted.

At the time I'm writing this, there appears to be about equal (hydro + gas) = (solar + wind). It appears they are running a significant portion of the grid with high inertia generators. In a control system when you have an actuator that is much more responsive than the load, you can get into instable operating regimes where. On a small scale, when you are setting up servo motors, there is an inertia matching ratio fo…

Seems like a simple cybernetics problem, especially if it's point-to-point. If there's many different inverters on the same circuit, you might need something like a directed graph, but there should be simpler, more local solutions.

bless you for your correct use of the C-word.

Re: Spain is about to face the challenge of a "black start"

#97

Post by jsjohnst »

pfdietz wrote: post #76
jsjohnst wrote: post #63

Earlier quoted context omitted.

Thanks for sharing the link! 1.3MW really isn’t that high of a load though. Thats a very straightforward load to be able to support via diesel generators. As an example, a typical large datacenter uses an order of magnitude more power, yet stays online following a grid outage.

It's 1743 horsepower.

Yep, you did the simple math. 2MW generators are rather common place, they even come in portable (as in on a trailer) form.

Re: Spain is about to face the challenge of a "black start"

#98

Post by zeristor »

myself248 wrote: post #95
zeristor wrote: post #46

I am no expert, however with solar power and more grid batteries (I don’t think Spain has many grid batteries) wouldn’t it be possible to charge the batteries and use that to drive a ‘black start’. Sounds simple, and I appreciate from experience a huge amount of prep and validation needs to be done in the background.

At an extremely abstract level, it is conceptually simple, but most inverters are designed with safeguards to prevent exactly this. They only produce power when the grid is up, and in phase with it. Because if not sequenced and interlocked, islanding behavior can result in back-powering parts of the grid that are supposed to be disconnected and down for maintenance, or creation of desynchronized islands that then cau…

Thanks for the excellent insight.

I’m guessing this could be more of a thing in the future to make the grid more robust.

Didn’t Australia have a similar issue a few years back, which Tesla built a large grid battery to resolve, not just for storage but for stability.

Re: Spain is about to face the challenge of a "black start"

#99

Post by justlikereddit »

atwrk wrote: post #85
justlikereddit wrote: post #45

Earlier quoted context omitted.

The groundwork for the blackout will inevitably come back to a buildout and reliance of renewable sources that do not have spinning mass that can do frequency synchronization. There are costly means to compensate for the lack of spinning baseload but actually building these devices have been neglected, to no ones surprise.

Not my area of expertise, but I think this is wrong? Modern PV inverters used in rooftop solar could easily start frequency synchronization autonomously, but are regulated to not do that autonomously in (at least) parts of the EU. More importantly, according to the REE, PV played a mayor role in the current and successful black start.

How?

If the power is out, do you imagine that all the load that is out there disappears too?

If I'm in a blackout and put my multimeter into the grid socket, will the measurement be something that my local inverter can drive an AC load through with no problems?

And if that's not possible, how do we get an AC wave out to my 5000 local solar panel neighbors? And if we don't get any carrier wave to synch it to, then how do all these thousands of individual inverters decide on the unison synchronization necessary to all start jumping together?

And if they try and fail, will all the connected load accept a graceful out of synch mixed power noise at 0-220v until things properly latch together?

The problem isn't like playing a sine tune of acoustic sound that's merely audible to your local neighbor, who can dial in his own tune, and then daisy chaining this until it matches on a grid sized level.

Re: Spain is about to face the challenge of a "black start"

#100

Post by ZeroTalent »

everyone wrote: post #81

What caused it? Nowadays when anything like this happens in the EU, I immediately wonder if it was Russian saboteurs. They have certainly been destroying infrastructure here, eg. undersea internet and power cables.

It was American saboteurs. First thing that comes to my mind /s
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