Thread by @douglewinenergy

#ERCOT update: New weekend record broken yesterday w/ 77.4GW; expected to be ~77.5GW today. Very low chance of outages today, somewhat higher (though still low) tmrw when 80.5GW expected.

At 9AM, 6.5GW of gas/coal is unavailable, up from 4.9GW yesterday AM.
#txlege #txenergy 1/

Yesterday, 500MW additional thermal (gas/coal) went offline as the day went on and overnight another 1000MW dropped. Hopefully some of those will come back on as the day goes on.

Remember, if there are rolling outages, they are likely to be short duration, nothing like Uri. 2/

If you want to help, pre-cool your home or business in the AM tmrw. In a well functioning market, if you choose to help, you'd be paid to do this. This function would be automatic & you'd keep the thermostat where you want it in the PM, just a little cooler in the AM. 3/

Here's why I think it's unlikely we'll have outages tmrw. You can see the math further down the thread, but it mostly comes down to 4 variables:
1) battery storage
2) thermal outages
3) combined wind & solar
4) #demandresponse from 4CP
#txlege #energytwitter 4/

Unaccounted for in ERCOT's Seasonal Assessment or on their dashboards is battery storage. Acc'g to the monthly "Capacity Changes" report released on Friday, there are 2.3GW of storage in #ERCOT now (= ~2 large nuclear plants)! This is making a difference on peak. 5/

Note this is an additional 600MW of storage (enough for ~100,000 homes) in only the last two months! Storage's rise is meteoric and should be encouraged for a host or reasons, but at the top of the list are reliability and resiliency. #energytwitter 6/

Gas/coal outages are greater than expected in the SARA (4.1GW). Hasn't been a day where they've been at that level. This AM they were >50% higher at ~6.5GW. Generators say that forcing these plants to be ready every day is degrading their ability to operate when most needed. 7/

Wind & solar are expected to be ~15.8GW tomorrow on peak, slightly below SARA expectations (~18GW).

Note, the SARA has lots of problems and isn't that useful as written, but you can plug in different numbers to see what happens, as I've done below.
#txlege #txenergy 8/

Another thing not accounted for in the SARA is 4CP. Large customers' bills are ~50% determined by how much power they use during the 15 minute system peak intervals in June, July, Aug, & Sept (4 coincident peak). Typically, we see ~2-3GW of demand reduction during these times. 9/

So when you take likely levels of storage, #demandresponse reductions from 4CP, wind & solar production, & thermal outages, you get a low likelihood of outages as you can see below. Note that w/out storage and DR (red and green columns), the likelihood would be much higher. 10/

The green column is one of the original scenarios in the SARA. The red and yellow I've added to reflect likely levels tomorrow (w/ some additional thermal outages).

Red doesn't include storage and 4CP while the yellow includes both. You can see the difference is large. 11/

This is why the SARA, as written, isn't that useful. You need more variations and variables to plot a probability curve and that's not what ERCOT does now. Still, storage & DR, though still underutilized, probably are the difference between outages and no outages.
#txlege 12/

As @AndrewDessler pointed out, the models can't keep up w/ this heat. The "outlier" years are far more likely than the models anticipate. ERCOT, PUC, & state leadership need to begin accounting for climate change. To deny it increases risks of outages. 13/

https://twitter.com/AndrewDessler/status/1545889136338419713?s=20&t=3UYOoF9plECYBjaRzzKnqA

As always, even w/ a low likelihood of outages, please check on medically vulnerable friends, families, and neighbors. Have a plan just in case. Even w/out outages, these temps are dangerous. Be prepared. I'll try to update again later today and tomorrow.
14/ End🧵