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Giant flywheel project in Scotland could prevent UK blackouts

theguardian.com

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Re: Giant flywheel project in Scotland could prevent UK blackouts

#41

Post by neltnerb »

tankenmate wrote: post #34
Ballas wrote: post #10

Earlier quoted context omitted.

What is different in this case is it is not really an energy storage system (at least that is not the main intended purpose), but only to provide stability to the grid frequency. A huge flywheel in a vacuum to provide a reference to millions of distributed PLLs. I don't think the idea is to always have it spin at a fixed rate with minimal losses. In the case where a flywheel is used as a UPS, the rate at which it is…

You can get constant spin rate but variable energy storage / release by adjusting the moment of inertia, e.g. if you have movable weights within the rotor you can move these inboard or outboard, moving it inboard uses energy while increasing the spin rate, and moving it outboard releases energy while slowing the rate. Using this in combination with "conventional" direct axle energy input / release means you can store…

Is this used in practice? It sounds like a rather substantial engineering challenging considering how much energy the wheel is storing. I remember MIT had one of these for sparking the old tokomak, they had to plan for it to fall off, destroy several buildings without killing anyone, and then land in the river... and that was a solid wheel that did nothing but spin.

But isn't the point that it provides inertia towards stabilizing the frequency? I don't think it matters whether you can vary the energy stored if it's just acting as a, well, wheel... if the goal is to give you a bit more time to bring more generation online or take it offline then it seems like a simple system would be fine. It's not storing power, so it can only ever slow the drift to give more flexibility.

Re: Giant flywheel project in Scotland could prevent UK blackouts

#42

Post by msandford »

tpmx wrote: post #39
MrBuddyCasino wrote: post #18

Those things have interesting failure modes. Will they have to be buried underground, or is this somehow a solved problem?

What happens if the grid frequency disagrees too much with the rotation frequency of the flywheel, too quickly? The flywheel disintegrates and turns into a massive spherical weapon of mass distruction? Like this, but 20x worse? https://www.youtube.com/watch?v=bdcE3VyKv5U

The spinning flywheel doesn't just spin on its own. It gets spun up and kept spinning by an electric motor/generator I have to imagine. So you're limited as to how much power can go in or out by the size of that motor/generator.

If it's a 100kw peak electrical machine then it can provide at most 100kw of instantaneous power to the grid while at the same time slowing down by however much is required to deliver that power.

If I understand correctly the idea is a lot like capacitors for DC voltage. The DC voltage has to go down in order for the capacitor to supply current, but the capacitor ensures that the voltage can't go down as quickly as it would otherwise.

Re: Giant flywheel project in Scotland could prevent UK blackouts

#43

Post by flohofwoe »

DrBazza wrote: post #27
happytoexplain wrote: post #19

Earlier quoted context omitted.

>The rest of the world just builds a dam, creates a new lake, and moves on. Your wording implies this is better than the flywheel solution - can you elaborate for a layman?

I'm just cynically generalising - the rest of world compared to the UK has typically less stringent planning requirements, and more mountainous terrain. To store energy in other countries (except perhaps Holland..!) you build a hydro dam, and pump water into those dammed lakes using excess electricity to store it up for later release. We have mountains (Wales, Lake District, Scotland), but the likelihood of creating…

Also, pumped-storage plants are massively big and expensive projects. E.g. the pumped-storage plant near my home town [1] (which I think was the biggest in Europe for a while) took two decades from planning to running [2].

[1] https://www.google.com/maps/@50.514101,12.8731705,3067m/data...

[2] https://en.wikipedia.org/wiki/Markersbach_Pumped_Storage_Pow...

Re: Giant flywheel project in Scotland could prevent UK blackouts

#44

Post by URSpider94 »

xhkkffbf wrote: post #32

Why do we care about keeping frequency stable when more and more products simply put the power through a rectifier to turn it to DC? The lamps all have LED "bulbs". The computers have power bricks. Do we really care if the compressors in the air conditioners and the refrigerators turn at a slightly different rate? Okay, maybe a rapid shift in frequency could be damaging, but a slight drift sounds okay mechanically. O…

In the electrical grid, frequency is proportional to voltage. When the frequency drops, it means that the supplied voltage is also falling. Likewise, if you go over-frequency, then the voltage will rise.

Traditionally, the inertia of thousands of tons of spinning generator turbines across the system provided this inertia, but with more and more nonlinear sources (and also nonlinear loads), that balance is disappearing.

Re: Giant flywheel project in Scotland could prevent UK blackouts

#45

Post by tankenmate »

neltnerb wrote: post #41
tankenmate wrote: post #34

Earlier quoted context omitted.

You can get constant spin rate but variable energy storage / release by adjusting the moment of inertia, e.g. if you have movable weights within the rotor you can move these inboard or outboard, moving it inboard uses energy while increasing the spin rate, and moving it outboard releases energy while slowing the rate. Using this in combination with "conventional" direct axle energy input / release means you can store…

Is this used in practice? It sounds like a rather substantial engineering challenging considering how much energy the wheel is storing. I remember MIT had one of these for sparking the old tokomak, they had to plan for it to fall off, destroy several buildings without killing anyone, and then land in the river... and that was a solid wheel that did nothing but spin. But isn't the point that it provides inertia toward…

As you say, I suspect it probably isn't used much in grid scale applications. The device image in the article would imply that it is just a simple damper, i.e. the angular momentum acts to reduce any frequency change, up or down. It doesn't look like it does any storage, but then the article is somewhat content free.

Re: Giant flywheel project in Scotland could prevent UK blackouts

#46

Post by adolph »

DrBazza wrote: post #8

This is a consequence of the UK having little capacity for pumped-storage, i.e. hydro-electric. We don't really have the height, and we have "areas of outstanding natural beauty" that cannot be built in easily, so we need alternatives to store the energy. The rest of the world just builds a dam, creates a new lake, and moves on.

Just put Thomas on the front of a train full of slate and everyone will love watching it go up and downhill as energy storage.

https://www.wired.com/2016/05/forget-elons-batteries-fix-gri...

Re: Giant flywheel project in Scotland could prevent UK blackouts

#47

Post by Someone »

verytrivial wrote: post #26

https://www.goodnewsfinland.com/teraloop-secures-eur-2-4-mil... - There's a Finnish company called Teraloop who've been chipping away at a more Sci-Fi version involving maglev and evacuated loops. Life gets difficult for this model because the heat induced due to current 'turbulence' and maybe skin effect gets 'stuck' inside the chamber. Fun engineering problems.

Even more Sci-Fi (I think; I couldn’t find definitive figures as to the size Teraloop aims for): https://www.ecn.nl/news/item/floating-train-at-2000-kmh-set-.... I don’t know whether that idea died on the drawing table since 2015, but I guess it could have.

Re: Giant flywheel project in Scotland could prevent UK blackouts

#49

Post by empyrical »

netsharc wrote: post #25
geocrasher wrote: post #3

Same article, no registration required. This site touts "Powered by The Guardian" and does not appear to be a scraper: http://www.execreview.com/2020/07/giant-flywheel-project-in-...

Looks like a content-stealing site thinking adding a PNG that credits the original source is enough to keep them away from trouble... The Guardian's registration nag keeps getting worse and worse, but there is still a button labelled "Not now" to bypass it.

It's from the Guardian Open Platform[1], which has a clause in the TOS[2] requiring that that the "Powered By The Guardian" logo be displayed where you display Guardian content

> Include a "Powered by The Guardian" logo (or such other Guardian logo as we may require from time to time) on the same webpage as any republished OP Content, or any tool or function that is based on OP Content. Such logo must be a reproduction of the "Powered By" file found at http://www.theguardian.com/open-platform/logos, and comply with any special terms set out by us. The "Powered by The Guardian" logo must not be used in conjunction with any content other than the OP Content.

[1] https://open-platform.theguardian.com/

[2] https://www.theguardian.com/open-platform/terms-and-conditio...

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