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Tesla Big Battery Outsmarts Lumbering Coal Units After Loy Yang Trips (reneweconomy.com.au)
The Tesla big battery is having a crucial impact on Australia's electricity market, far beyond the South Australia grid where it was expected to time shift a small amount of wind energy and provide network services and emergency back-up in case of a major problem. From a report: Last Thursday, one of the biggest coal units in Australia, Loy Yang A 3, tripped without warning at 1.59am, with the sudden loss of 560MW and causing a slump in frequency on the network. What happened next has stunned electricity industry insiders and given food for thought over the near to medium term future of the grid, such was the rapid response of the Tesla big battery to an event that happened nearly 1,000km away. Even before the Loy Yang A unit had finished tripping, the 100MW/129MWh had responded, injecting 7.3MW into the network to help arrest a slump in frequency that had fallen below 49.80Hertz.
Trying to remember why it wouldn't have worked. Because it might steal their market share? Yeah pretty sure that was their reason they didn't think it would.
Read up on generators and how demand influences frequency.
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The grid worked as designed. News at 11.
Steam plants don't come online in 6 seconds, they just don't.
First the UPSs, then load curtailment, hydro and combustion turbines, finally the steam plants and steam parts of combined cycle plants.
The real point (beyond the usual /. 'Ol Musky' blowing) is that apparently Australia was in spinning reserve violation when this happened. Your supposed to have enough power spinning to cover you single biggest unit/transmission line falling over (as they say in Australia).
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
The narrative and conclusions are a big dodgy. Everybody knew beforehand that batteries can jump in immediately to supply power. And the batteries did not stop a complete collapse, electrical networks are thoroughly analyzed and simulated and braced against major consequences if any one unit trips out. Major outages are quite rare over the decades, and all done without a single battery. Gas turbines can come on-line within 60 seconds and other interconnected plants often have enough reserve capacity to tide over small outages. Batteries are welcome as an immediate source, but they are still awfully expensive and awfully small in GWH.
Electricity grids are stacks of eggs balanced on their point. A single snow event taking out a single line in the US took out millions of people for days, in a very populated and "modern" area.
The Australian grid may have failed. The current was out of spec. If protection circuits activate, they'd shut down the grid. Tesla didn't fill all the missing need, but injected enough power in an "our of spec" event to ensure the grid couldn't fail from that event.
That small boost may have saved a major catastrophe. We may never know. But that it could is a great proof of concept. Battery-based storage can react faster than anything else on the grid, to smooth grid failures to prevent cascades. Now we know, we need them all over the US, before the next snowstorm in the North East.
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Grid level power management is utterly unlike your home UPS.
I think the article is overstating a bit given the scale, but the macro implications are impressive. Grid-scale generators are slow to ramp up and down - minutes to hours (or even days for startup of nuclear plants). Small, less efficient generators handle the small peaks (oddly enough, called peaking generator) that go beyond baseline generation and any under-utilization goes to waste so it's a careful balancing act. And even the peaking generators aren't instant response whereas the Tesla Battery IS essentially able to go from 0-100MW in moments (they should advertise this along with the Tesla speed records). This allows highly efficient supply of peak-demand (or, in this case, unexpected demand) which is pretty much unheard of.
Having 500MW go offline suddenly does Bad Things to the overall grid. Remember when one plant tripped offline ... I think in upstate NY and blacked out most of the northeast in a cascade failure several years back? Having something able to take a near-instantaneous load, even for a few minutes, is a massive benefit.
You can get rich if you own a politician, but you have to be rich to buy one in the first place.
The coal plant that failed was producing close to 600MW. The max output from the graph in the article showed the battery system inject less than 10MW max into the grid. Who pickup up the other 500+ MW? The other coal plant that came online within 6 secs. Basically all the batteries did was reduce the size of the brownout.
The "spinning reserve" generally picks up the demand. "Spinning reserve" consists of machines which are on the grid but not at full load. The spinning reserve should be a minimum of the sum of the largest individual generator + the maximum estimated demand change that could happen in around 10 minutes (the time it takes for a gas turbine to start up). Generally, all that is necessary to change spinning reserve into real power is for a valve to be opened further. For combustion or steam turbines, this can occur in less than a second, and is automatically controlled by the generator controller - the generator demand signal will increase as grid frequency decreases. Spread across many generators, the increase in output is not a significant shock to any individual generator.
In this case, it seems that the Australian grid did not have adequate spinning reserve, which is why the frequency dropped. Many power stations are set to shut down in the case of large frequency variations (for machine protection), which caused the coal power station to shut down.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
It didn't respond too rapidly. The frequency was below the absolute minimum of 49.85Hz for normal operation.
Just putting out a wild idea: they configured the battery to kick in at 49.80Hz on purpose.