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Comment by eldaisfish | Hacker News Reader

What you have in mind requires someone to do the coordination. that is currently the system operator and they operate at a data rate measured in minutes or 4 s for the fastest changes (e.g. PJM).

Meanwhile, solar output can go from 100% to 10% in three seconds. How is this not a problem?

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PJM has "Regulation D" signals for sub-second response from energy storage resources (which are mostly batteries in practice):

https://www.pjm.com/~/media/committees-groups/task-forces/rm...

An energy storage regulating resource, such as a battery or flywheel, cannot burn fuels to produce electricity, but instead charge and discharge energy from the bulk electric system itself through a power inverter. Energy storage devices can match a desired output within 200 milliseconds of receiving the regulating signal; therefore these resources do not need to model any dynamics, ramp limitations, or dead-bands.

Australia is also using batteries in a similar way:

"South Australian Battery Responded in Just 140 Milliseconds After A Coal-Fired Power Plant Failed"

https://www.sciencealert.com/elon-musk-s-south-australian-ba...

One thing I've learned recently is that grid management is extremely primitive. People are literally emailing each other word docs and pdfs and calling each other on the phone to make changes to generation output to keep the grid stable.

It's an area that's ripe for some software innovation, if they can actually break through the legacy management club that currently runs the grid.

I, for one, can't wait for the first ever Western Interconnect black start, brought to you by an off-by-one error. During a megadrought.

There are already companies working on that https://www.emsysgrid.com/products/grid_management/futurepow...

The problem anonporridge was talking about was the 10% of solar meeting the current demand and then suddenly going to 100% in three seconds, so there's 'too much' power on the grid i.e. overprovision breaking things. Which it doesn't.

While your example is solar at 100% exactly meeting demand, and then dropping to 10% in 3 seconds, and the fix for that is: overprovision (and some other stuff).

They do need to have decent predictions of demand and supply, like this graph that shows the 1-hour ahead and 24-hour ahead predictions:

https://www.caiso.com/TodaysOutlook/Pages/default.aspx

To get the whole grid working together, but we already have that, and renewables and batteries help in various ways.

Well, you need a 30 minute battery buffer to get gas peakers online. Whether those gas peakers are running natural gas or green hydrogen depends on how much excess solar capacity there is and how much hydrogen plants cost.

Also, medium term storage is a very, very young industry. Things like redox batteries, flow batteries, molten salt, compressed air, and many others are on the horizon. The better these work the more gas peakers are solely used as backup.

Thermal storage, like resistively heated sand, can also act as a backup source, since once the sand is exhausted they could then resort to burning something to get the heat.

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