Induced atmospheric oscillations.

Exactly

Should does not equal is.

Exactly

Who *pays* for the batteries? Its the tragedy of the commons.

I don't know any way to extract energy more safely from nuclear fuel yhan by a steam turbine, except in micro amounts.

The Luddites are those who want 1000 year old windmills to power the grid

There are not nearly enough expensive batteries on anyone's grid to take care of the lack of spinning inertia.

In any case my contention was that the claim that a 'renewable grid needs less spinning inertia' is utter bollocks.

The amount of lies that the renewable shills spew out is monumental

They are s*it scared that the game is up, and that renewable energy is not only dead, but beginning to smell

That isn't in fact correct. Heaven forfend that I should defend renewable energy but the issue is that as the frequency drops, no renewable source can deliver more power automatically. There just isn't any to be had so the grid will drop frequency in an instant by a huge amount.

The batteries are able by careful design to add short term power , because they can deliver power up to the maximum capacity of the batteries available.

And so does spinning mass on the grid.

This very short term storage is *inherent* to generator designs that use turbines and alternators - all steam, and gas plant and hydro.

It is absent from wind and solar. Not because they use inverters, but because they have no inherent energy storage. Even the windmill rotors which should have, don't because back feeding massive power fluctuations into the moving parts would destroy the gearboxes in short order.

The same arguments is there for HVDC links. There is very little inherent storage in the cable's capacitance, although when I visited the countries first HVDC plant the engineer boasted that 'we can draw an arc for 20 minutes off the cable capacitance after we switch it off'

You could solve the problem using e.g, rotary inverters. At greater cost. I took a flight years ago from Farnborough in an Elizabethan because my friends dad was a boffin in the Decca radar company, The aircraft was crammed full of electronics and an enormous lump of what looked like an electric motor .

'What's that?' I asked. "Rotary inverter" said the flight engineer. "Why rotary, Wouldn't transistors be lighter " He grinned.

"We have 48V batteries on this plane, Except when we pull the gear up, Then its about 28V, and this was the easiest way to stop all the electronics needing to be reset"

Its a good thing aeroplanes are designed by EU politicians.

Well as I explained earlier, inverters do not provide a tight coupling between any inherent storage in the source and the grid.

If grid demand goes up the inverters will simply disconnect to avoid damage.

Its a bit like everyone having switched mode power supplies in their homes. They will draw constant power no matter what the voltage and frequency are so that dropping the voltage and frequency on the grid will not reduce e.g. domestic demand in the same way that motors and incandescent light bulbs would respond

Renewable energy is in the end not designed to meet engineering targets of stability and reliability, it is designed to meet the *political* target of the EU 'Renewable Obligation' directive.

That directive contains no specification on how reliable or otherwise the delivery should be. So it isn't factored in to the design. Grid stability becomes 'someone else's problem' - typically the grid operator, who has to spend the money on battery storage. Or not. As the case may be.

And the delivered cost of electricity goes up while the renewable people say 'but we are cheap'

So the proximal cause of grid collapse is the inverters, but the real cause is in fact lack of short term overload storage on the grid.

Undertaking such a highly detailed investigation may well produce much information but is also delays addressing public concern. This is more than just a technical exercise because one of the stakeholders is the public, who have been very adversely affected.

A quick early-release report could be produced within one or two weeks and then a technical report and analysis could come many months later.

SAo far so good

How do they know what frequency to keep it stable AT.?

They monitor the grid frequency and they feed in at *that* frequency.

That frequency is allowed to drop as a signal that overload is underway. At which point voltage should also drop and the load on the grid thereby drop. And grid operators will signal steam plant to open up the throttles a bit and add more coals etc. heating and lighting loads on the network, plus the rotational inertia in the synchronised generators makes for a grid that doesn't suffer uber rapid changes, even if a power station trips out.

Renewable energy is designed to feed *into* a stable grid. It is not designed to BE a stable grid in isolation.

The problem is what happens if the grid frequency goes out of spec and the voltage drops too far. Your cells will simply disconnect to avoid damage.

Indeed. The 'priximal causse'

You have a less than full understanding here.

Inverters don't 'change frequency' under load , true, they change frequency to match the grid, which itself changes frequency under load.

It is the change of grid frequency and voltage which is supposed to reduce demand and allow the generators to keep up. Negative feedback

Renewables are simply slaved to that so that irrespective of system frequency or voltage they will deliver maximum power to the grid.

There is simply no negative feedback there at all. In fact there is

Hence the cascade failure.

Oh everyone knows already. The renewable shills are out blowing smokescreens, but the word on the street is 'renewables' . Everyone has been predicting exactly this scenario bit were of course ignored.

I think I didn’t put my point across very well.

I was thinking of the case, like that of the recent Spanish issue, where renewable energy supplied via inverters was dropping out generator by generator due to some initial fluctuations in grid frequency exceeding the operating limits of those inverters.

But a battery storage has under these conditions to supply energy via its inverters, and unless they are designed to start up and supply power to a grid that’s shutting down and off-frequency - and I’m not sure how that could be done - they won’t be much help. But, of course, ICBW.

A fascinating story! BAE Airspeed Ambassadors were known as Elizabethans, and I can still recall seeing the newspaper photos of the 1958 crash at Munich.

The point is this Renewable inverters will react pretty much instantaneously to a loss of system frequency.

As they disconnect, the rotating mass generators wont drop frequency, they will trip themselves. As will grid interconnections to e.g. France.

My guess is that something popped in the Spanish grid, causing overload. The Spanish grid started to try and pull more from France, and those interconnects popped as well. The Spanish grid is now isolated and overloaded with its frequency out of step from Europe's grid.

The voltage and frequency start to plummet, to the point where the nuclear and gas trip as well - they simply cannot supply the excess - and the the renewables having no surplus simply give up in disgust and go for a siesta.

This probably takes no more than a second.

Ultimately its a case of overload and no spare capacity whatsoever in the sub second area.

Because renewables have no storage.

Its a problem that can be fixed with batteries, at great expense, or by building more thermal plant at way less expense, especially if the renewables are de-subsidised and taken off the grid.

Which will now happen all across Europe I think

It doesnt have a local energy store. That is the point.

Indeed, and that is exactly what those battery farms have. But they cost a lot of money and do nothing to meet 'renewable obligations' so why build them?

However do not underestimate the energy storage in a few tons of rotating steel iron and copper turning at 1500 RPM

For very short durations the rotating mass would be able to supply several times the power that they are rated at for continuous usage..

The problem is that there is a limit, even for that. If they are required to deliver more for longer, they will trip.

Renewables will just trip immediately.

Ultimately the rotating mass is supposed to be enough to keep the grid up enough to isolate the fault and disconnect that from the rest of the grid or bring extra hydro or gas online to meet demand. But that takes more time than is available without the inertia

The grid is a complicated beast and its been developed by trial and error to have as much backup plant as is needed at ultra short, short, medium and long terms, to keep it up.

Until politicians insisted on throwing as much renewable energy at it to meet political, not operational, targets, as possible.

Indeed, RRs SMR has now completed phase II of its paperwork boondoggle, and has only one phase left to go.

Compared with that building reactors and pouring concrete is a relatively short period of time

Maybe 2-3 years only.

Deliberately generated in order to slow down approval.

(i) Declare that *for safety* every reactor must have detailed approval of *everything*.

(ii) De fund the Office of Nuclear Regulations to ensure that it takes forever to approve the last M5 bolt in the control panel etc.

(iii) Declare that 'nuclear power is just too expensive and takes too long to build'.

Hence the reason for type approved SMRS, You only go through that once for every design change. Once stabilised, pop one of the production line every month for ten years

Economies of scale....

RR SMR has passed through GDA steps 1 & 2 already...

The fossil fuel lobby is not the one opposing nuclear.

Even if every gas and coal plant were to close tomorrow there is still a huge market for fossil fuels .

No - the question that dare not ask itself is:

"If we deploy nuclear power, what justification is there for more expensive and less reliable renewable energy?"

And the answer is 'Absolutely none'.

THAT is what is at stake here

I love Kathryn. She does all the detailed fact finding and analysis I am simply too old and tired to do myself.

If only politicians would listen to her...

Oh, they are designed exactly for that.

Consider the logic of a *renewable* inverter:

Monitor mains frequency. IF within limits THEN add as much power as available ELSE disconnect

Compared with a battery inverter:

Monitor mains frequency. IF above lower limits THEN charge battery ELSE use battery to power network...

IF *well below* limits THEN disconnect

No one is expecting them to do a black start. But they are capable of removing excess power or supplying power deficiencies over a broader range of grid parameters

LOL…I know the feeling…

Speaking truth to power (IYSWIM) isn’t usually a good career choice…

Thanks Spike, that is the best thing I've seen so far.

Still confused, but it leads to a bit of an understanding. Seems to be a standard human nature problem. Previously, change in frequency was naturally resisted by the technology used, so grid operators didn't think about it much. They didn't measure it, they just flew by the seat of their pants, and things were kind of OK. It appears they haven't considered the implications of non turbine sources enough (e.g. inverters)

I still don't understand this "Frequency management insight":

"Inertia is distinct from the fast injection of active power after a measurement delay, often referred to as synthetic inertia".

This is actually an example why we need the precautionary principle. If something doesn't go wrong in the environment we are familiar with, we shouldn't just assume it won't go wrong in a different environment. We shouldn't assume things naturally just work. Something we tend to do.

The PhD paper is irritating, introducing equations without explaining what the variables are. I always think PhD papers should be competent, but they are written by people little more than children, who have never actually had a professional job. They lack those basic, simple communication skills we have kicked into us at work. Or at least the skills kicked into the people who do write papers.

Wha`t te calculatins and measurements showed is that the energy stored due to inertia was roughly equivalent to 9 seconds of full grid power. And that was an issue that caused out of spec operation. Ideally maybe

With more renewables the constant can be down to 3 seconds. That simply isn't enough tome to react to a falling frequency

There is a delay for the injection to happen, and its never as smooth or uniform as simple grid synchronous inertia, I think.

That isn't the precautionary principle. That is simple worst case analysis with known probabilities.

The 'precautionary principle' is ideological nonsense that takes no account of the costs or consequences of prophylactic behaviour.

Precautionary principle:

"Why are you tearing up newspapers and throwing them out of the train window?" "It keeps the elephants away" "But there are no elephants!" "Its amazingly effective isn't it?"

Worst case analysis:

"What level should we stress the airframe to? " "well as high as is feasible. We don't want the aeroplane falling apart" "but lets say we stress it to 10g, like a fighter jet. The passenger will be dead from being thrown about anyway, and the pilots will probably be unconscious, so what is the point? And it will burn so much fuel because it is so heavy that no one will buy it anyway" "Ok well what is a reasonable factor that covers all but a one in a million event?" "Probably about -2g to + 4g. That is going to cause severe passenger trauma, but the pilot should be able to get the airframe down" Etc.

Ah., you didn't understand it then.

Ah, obviously I don't know Spain well enough.

I'd assumed that the aircon load would be during the hottest part of the day, which would be in the afternoon. Not after dark.