Solar PV/thermal + wind: ~78%
Nuclear: 11.5%
Co-generation: 5%
Gas-fired: ~3% (less than 1GW)
This is (a) incredibly impressive to achieve and (b) definitely the point at which the battery infrastructure needs to catch up in order to reduce the risk of such incidents.
This non-existent technology will surely catch up very soon, I wonder what takes them so long.
The only battery available at this scale is hydro and it doesn't do very well in Spain because of droughts.
Makes the case for favouring flywheels over batteries.
http://claverton-energy.com/active-power-article-flywheel-en... as a smaller scale example. $330/kW but at that price it only has 15 seconds of carry-over, basically just enough to get the diesel generator fired up.
Spinning reserve in the grid is equipment that capable of long-term generation very quickly. In the case of hydroelectric dams, they will often cut off the water supply to some of the turbines and use air pressure to push the water out of the way; the generator attached to the turning essentially turns into a motor and keeps the turbine spinning. If you need to bring it online, you open the water valve and let the air out.
Similar situation with natural gas-fired simple cycle turbines. They’re sitting there running at low output. Need more? Just add fuel. For combined cycle it might take a bit for the boiler to warm up for full output but having the first stage running full tilt will get it warmed up fast.
In a solar grid you probably have milliseconds instead of seconds, this could be the reason why the automation failed in this case.
https://www.proactiveinvestors.co.uk/companies/news/1057463/...
That's insane, imagine if it let go.
Or if you consider the Irish grid (average consumption around 5 GW) that's enough energy to power the grid for about 0.8 seconds (obviously it's not going to have enough instantaneous power output to do that, but again for a sense of scale).
If Ireland had 10 of them, that'd be 8 grid-seconds worth of energy. Although, of course, actual disturbances aren't going to be that large. A few percent imbalance perhaps?
So if the whole grid had an instantaneous 10% imbalance, one of those units could carry it for 8 seconds.
(EDIT: changed energy numbers to fit the appropriate power grid)
See also: https://en.wikipedia.org/wiki/Aeolian_harp
Edit: might be a completely different kind of oscillation than I was thinking of. https://news.sky.com/story/spain-portugal-power-outage-lates...
So I would also like to understand how this works :)