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193 points leymed | 2 comments | | HN request time: 0s | source
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AnotherGoodName ◴[] No.44360099[source]
Reads very similar to some blackouts we had in Australia. Weakly connected grids with vast geographical distances leading to oscillations that took down the grid.

https://en.wikipedia.org/wiki/2016_South_Australian_blackout

Completely solved with lithium based grid storage at key locations btw. This grid storage has also been massively profitable for it's owners https://en.wikipedia.org/wiki/Hornsdale_Power_Reserve#Revenu...

Australia currently has 4 of the 5 largest battery storage systems under construction as a result of this profit opportunity; https://en.wikipedia.org/wiki/Battery_energy_storage_system#...

You can also read numerous stories of how Australia's lithium ion grid storage systems have prevented blackouts in many cases. https://www.teslarati.com/tesla-big-battery-south-australia-... The fact is that the batteries responsiveness is the fastest of any system at correcting gaps like this. 50/60hz is nothing for a lithium ion battery nor are brief periods of multi-gigawatt draw/dumping as needed.

There's even articles that if Europe investing in battery storage systems like Australia they'd have avoided this. https://reneweconomy.com.au/no-batteries-no-flexibility-spai...

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londons_explore ◴[] No.44360187[source]
> nor are brief periods of multi-gigawatt draw/dumping as needed.

Actually this is typically an issue for grid batteries.

Spinning generators can easily briefly go to 10x the rated current for a second or so to smooth out big anomalies.

Stationary batteries inverters can't do 10x current spikes ever - the max they can get to is more like 1.2x for a few seconds.

That means you end up needing a lot of batteries to provide the same spinning reserve as one regular power station.

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ajross ◴[] No.44360936[source]
That... doesn't sound correct. Inverters are the cheap part, you can literally wire as many as you want in parallel. Batteries have immense power availability, with most chemistries you can trivially deliver the entire capacity in half an hour or so (more like 5 minutes with lithium cells).

Basically I'm dubious. I'm sure there are grids somewhere that have misprovisioned their inverter capacity, but I don't buy that battery facilities are inherently unable to buffer spikes. Is there a cite I can read?

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AnotherGoodName ◴[] No.44361006{3}[source]
Agreed. The relatively small battery substation linked above can output 2GW of equivalent inertia generation (a measure to align batteries to inertial power systems) when needed. That's an entire power station they can match for short periods of time. Link: https://www.energymagazine.com.au/sa-approves-world-first-ba...

Australia's largest power plant has 2.9GW of inertial generation assuming all generators are running at 100%. As in the small battery substation alone comes close to the countries largest power station. I'm not sure where the idea that lithium ion can't dump power quickly comes from. They are absolutely phenomenal at it. Australia's building dozens of these substations too since they are so cheap and reduce overall power costs. It's a win from all points of view.

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1. bob1029 ◴[] No.44363704{4}[source]
The article does not describe an inertia constant. Without the time component, any comparison to traditional systems is meaningless. Inertia is a measure of energy, not power.

Large spinning masses can provide several seconds of inertia. For 2GW of traditional turbine, you would have between 10-20 gigawatt-seconds of energy that is instantly available at any moment to resist RoCoF.

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2. ajross ◴[] No.44365282[source]
The switching rate of a good power MOSFET has a bandwidth in megahertz. It's... all solid state electronics. Again, this is just wrong, absent someone showing a cite. It's very weird seeing this kind of seeming ignorance of basic electrical engineering on a hacker site of all places.