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To free the Baltic grid, old technology is new again

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Re: To free the Baltic grid, old technology is new again

#151

Post by ZeroGravitas »

1970-01-01 wrote: post #52
crazygringo wrote: post #47

Earlier quoted context omitted.

Can you point to resources explaining why they're a good choice? Because the general consensus seems to be that large things like pumped hydro are good for centralized energy storage, while batteries are the choice for decentralized energy storage -- whether in your utility closet or in your EV. Why should anyone choose a flywheel over a battery?

https://amberkinetics.com Advantages over chemical batteries: >85% round trip efficiency (DC) >No daily cycling limitations >No degradation over time >Full power over full State-of-Charge range >No HVAC required >Operates in hot and cold environments (-20C to 50C) >Fast response time ( >Sustainable and recyclable all-steel design >Safe & reliable–no fire hazard >Lower O&M cost >30-year design life

At least two of these (85% efficiency and fast response time < 1 sec) are factually incorrect if presented as an advantage of flywheels over batteries, which do better on those metrics.

Re: To free the Baltic grid, old technology is new again

#152

Post by tuukkah »

chx wrote: post #150
tuukkah wrote: post #141

Earlier quoted context omitted.

Surely you mean this peace that ended when Russia started a full-scale invasion in Ukraine.

This peace, by and large, is about the lack of entries with other Western European countries on https://en.wikipedia.org/wiki/List_of_wars_involving_Germany By that measure, you'd consider the peace ended in 1956 when Russia -- then called the Soviet Union -- re-invaded Hungary after very briefly withdrawing. (As an aside, when the National Bank of Ukraine last year opened two donation accounts, I sent 1956 EUR to bo…

I don't know what 1956 felt like in western Europe but the current situation definitely doesn't feel like peace even though the war is not fought in western Europe. The war is at the EU border with stray missiles and overreaching Russian attacks already having hit EU territory.

Re: To free the Baltic grid, old technology is new again

#153

Post by hoseja »

wolverine876 wrote: post #136
Waterluvian wrote: post #127

Earlier quoted context omitted.

Seems like the trick really is to deeply intertwine economies. It kind of feels similar to how monarchs tried to form lasting peace further back: inter-marry so that everyone is someone’s cousin they grew up with. Of course that didn’t exactly work perfectly.

> Seems like the trick really is to deeply intertwine economies. On one hand, I read experts say that. On the other, I read experts point out that it failed to prevent WWI. I wonder what the consensus is, if there is one, and what the evidence is.

But the economies were not so intertwined. The British, French, etc. were massively profiting from exploiting their colonial holdings while the Germans and Austro-Hungarians were being left in the dust, slave labour abolished some decades or centuries ago.

Re: To free the Baltic grid, old technology is new again

#154

Post by londons_explore »

applied_heat wrote: post #125
londons_explore wrote: post #104

Nearly all of the purposes for these flywheels could equally be met with existing infrastructure with software only changes. Solar inverters can produce/absorb reactive power easily - but while that can frequently be configured from the control panel of individual units, rarely is that ability exposed to grid operators. Inverters at DC undersea links can do the same. As can some kinds of wind turbine. All three can a…

In the case where a system splits and one area is 6.3 GW in deficit how is an inverter going to conjure up that power? The only thing that can help in that case is batteries. 98% of the power plants I’ve been to run the voltage regulator in voltage control mode with 5% droop. Solar and wind farms can do that too, and I am sure it is required by the system operators to allow them to connect. If grid operators want mor…

This isn't to deal with multi-minute power deficits in split grids. That is dealt with with fast acting generation or load shedding.

Solar and wind systems today typically do not have a voltage setpoint or control loop. That's because there is no big gas/steam valve to adjust the amount of power generated. The operator wants to inject all the power from the sun/wind into the grid, whatever the voltage.

An X% droop would be X% of the total generated energy wasted in the name of stability. Thats a lot of money, and they won't waste it unless required to.

Instead, power deficits in the 10's of millisecond range can be dealt with by inverters (which typically have storage capacitors for ~20ms worth of output). This covers large fault currents, and sudden inflows as bits of grid are reconnected.

Unfortunately, most of today's inverters, which have the capability to do that, will not, due to having code which will only operate the 'happy case'.

Re: To free the Baltic grid, old technology is new again

#155

Post by natmaka »

PartiallyTyped wrote: post #58
chx wrote: post #31

As an aside, one of the most stunning proofs of how successful the European Union is happened with the grid. On 8 January 2021, the synchronous area of Continental Europe split into two, the system separation resulted in a deficit of power (approx. -6.3 GW) in the North-West Area and a surplus of power (approx. +6.3 GW) in the South-East Area, The reaction speed was something to behold. The event happened at 14:05 CE…

I found this article from bloomberg on the event! > Europe’s grid, which is usually connected from Lisbon to Istanbul, split into two as the northwest and southeast regions struggled to keep the same frequency. The problem originated in Croatia and led to the equivalent of 200,000 households losing power across Europe. Supply to industrial sites was cut in France and Italy. > Transmission grids need to stay at a freq…

> I knew we had an interconnected grid, but I had no idea it span from

WP articles about this: https://en.wikipedia.org/wiki/Synchronous_grid_of_Continenta... https://en.wikipedia.org/wiki/European_super_grid

Re: To free the Baltic grid, old technology is new again

#156

Post by justsomehnguy »

tuukkah wrote: post #152
chx wrote: post #150

Earlier quoted context omitted.

This peace, by and large, is about the lack of entries with other Western European countries on https://en.wikipedia.org/wiki/List_of_wars_involving_Germany By that measure, you'd consider the peace ended in 1956 when Russia -- then called the Soviet Union -- re-invaded Hungary after very briefly withdrawing. (As an aside, when the National Bank of Ukraine last year opened two donation accounts, I sent 1956 EUR to bo…

I don't know what 1956 felt like in western Europe but the current situation definitely doesn't feel like peace even though the war is not fought in western Europe. The war is at the EU border with stray missiles and overreaching Russian attacks already having hit EU territory.

> Russian attacks already having hit EU territory.

On 15 November 2022, a missile struck the territory of Poland at the village of Przewodów near the border with Ukraine, killing two people.[1][2][3] ... It was the first incident of a missile (vis-a-vis prior UAV incursions) fired from Ukrainian army[6] landing and exploding within NATO territory ... Initially Ukraine accused Russia of striking Poland,[9] while United States claimed that the missile was likely to have been an air defence missile fired by Ukrainian forces at an incoming Russian missile.[10][11][12] This was later confirmed in September 2023 by the Polish Prosecutor's Office, which stated that the explosion was caused by an out of control air-defence missile S-300.[6][13]

Re: To free the Baltic grid, old technology is new again

#157

Post by lhopki01 »

Waterluvian wrote: post #127
rbanffy wrote: post #94

Earlier quoted context omitted.

The EU itself is a thing to behold. Just managing to prevent wars between their members for so many decades is a remarkable accomplishment, unheard of in the continent's troubled history. Not perfect, and certainly not invulnerable to bad actors, but still a beautiful accomplishment of will and politics.

Seems like the trick really is to deeply intertwine economies. It kind of feels similar to how monarchs tried to form lasting peace further back: inter-marry so that everyone is someone’s cousin they grew up with. Of course that didn’t exactly work perfectly.

Intertwined economies are part of it but I think people underestimate the importance of norms. EU leaders and ministers are regularly in meetings together. When there is a crisis now the reaction of all EU leaders is to hold a conference for them to hash out how to deal with the situation. This establishment of the norm of talking whenever there's an issue is very powerful.

Re: To free the Baltic grid, old technology is new again

#158

Post by mistrial9 »

hoseja wrote: post #153
wolverine876 wrote: post #136

Earlier quoted context omitted.

> Seems like the trick really is to deeply intertwine economies. On one hand, I read experts say that. On the other, I read experts point out that it failed to prevent WWI. I wonder what the consensus is, if there is one, and what the evidence is.

But the economies were not so intertwined. The British, French, etc. were massively profiting from exploiting their colonial holdings while the Germans and Austro-Hungarians were being left in the dust, slave labour abolished some decades or centuries ago.

no mention of the gold hoards of Spain ? it rocked the continent at the time

Re: To free the Baltic grid, old technology is new again

#159

Post by wolverine876 »

chx wrote: post #149
wolverine876 wrote: post #138

Earlier quoted context omitted.

Official reports can be self-serving, both intentionally and unintentionally (it represents only one perspective). Journalists talk to many sources with many perspectives.

Journalists might but the publication which did the supermicro spy chip story without retracting it does not deserve that moniker. (Small footnote: I was a columnist, later editor, even later part of the editorial board of the largest computer monthly in Hungary in what now feels like a different life a quarter century ago.)

> the publication which did the supermicro spy chip story

How is that related to what we're talking about?

> does not deserve that moniker

That's pretty extreme. One story you didn't like, and that's it? I don't think anything, certainly not press releases, will meet your standard.

Re: To free the Baltic grid, old technology is new again

#160

Post by applied_heat »

londons_explore wrote: post #154
applied_heat wrote: post #125

Earlier quoted context omitted.

In the case where a system splits and one area is 6.3 GW in deficit how is an inverter going to conjure up that power? The only thing that can help in that case is batteries. 98% of the power plants I’ve been to run the voltage regulator in voltage control mode with 5% droop. Solar and wind farms can do that too, and I am sure it is required by the system operators to allow them to connect. If grid operators want mor…

This isn't to deal with multi-minute power deficits in split grids. That is dealt with with fast acting generation or load shedding. Solar and wind systems today typically do not have a voltage setpoint or control loop. That's because there is no big gas/steam valve to adjust the amount of power generated. The operator wants to inject all the power from the sun/wind into the grid, whatever the voltage. An X% droop wo…

> Solar inverters can produce/absorb reactive power easily

> Solar and wind systems today typically do not have a voltage setpoint or control loop. That's because there is no big gas/steam valve to adjust the amount of power generated. The operator wants to inject all the power from the sun/wind into the grid, whatever the voltage.

reactive power being easily controlled is the same as a voltage control loop with droop when connected to a larger system.

Control of the traditional prime mover by way of devices like steam throttle valve controls real power (MW) and not voltage or reactive power (MVAR).

I am curious how an inverter operating away from unity power factor fails to deliver roughly the identical amount of energy as at unity. Can you provide a link that explains it? Traditional generators pump out the same MW barring losses due to increased current no matter the power factor. MW in mechanical * efficiency = MW out electrical. And of course there is a limit to how out of phase the voltage and current waveforms can be, usually +/- 0.9 pf.

A 60Hz cycle is 16.7 ms, A 13 kV breaker takes 80ms to open, to detect a fault (except for differential element) let alone clear it takes a lot longer than 20ms.

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