On July 13, ERCOT was within ~1400MW of outages. Reserve margin was <2%. The PUC & ERCOT called for conservation at noon. In the 24 hrs before that call, an add'l 2.6GW of coal & gas plants went offline, driving the total “dispatchable” sources unavailable to ~15GW. #txlege 1/🧵
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Despite a focus on wind, it was not a low wind day. It was a low thermal day. ERCOT defines low wind as 2,874MW. At the peak hour of 5pm on 7/13, wind output was 6,752MW, ~230% of the low wind value. ERCOT expects only 4-8GW of thermal outages and got closer to 15GW. #txenergy 2/
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Here are the plants that went offline:
’s Parish plant had more problems. Recall Unit 8 (coal, 610MW) went offline in May & is still off.
In the early morning hours of July 12, Unit 6 lost 44% of its capacity as 289MW was offline. 3/
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Parish *by itself* accounts for >5% of all Texas power sector emissions. The 1970s coal plant is in the top 10 nationally for deadly pollution.
According to Rice researcher and scientist , it kills 177 people every year. #txlege #energytwitter
drive.google.com/file/d/1b94Cgc
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At 10:30AM on 7/13, just an hour before the conservation alert, all 391MW of South Texas Electric Co-op’s San Miguel coal plant went down. It features the dirtiest coal ash retention “pond” in the country according to this article.
#txlege 5/
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In addition to the ~1GW of power lost from Parish, which is pushing hard for add'l payments for these “dispatchable plants” lost 377MW of power from Cedar Bayou gas plant on July 12 & 127MW from their Limestone coal plant, putting their total near 1.5GW.
#txenergy 7/
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Once again, ERCOT’s communications were awful. At noon in its conservation call, ERCOT said 13GW of “dispatchable” were offline. Not dispatchable generation or coal & gas (all nukes were online) just “dispatchable.” This is, to say the least, not very helpful. 8/
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At the Technical Advisory Committee at ERCOT last week, the Independent Market Monitor asked why ERCOT used installed capacity. It's not a useful number.
covered why not here today. #energytwitter 9/
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The IMM: “It was very difficult to determine from the conservation watch” what was the "actual thermal outaged capacity" & suggested “new dashboards” to track it. Note ERCOT shows hourly wind & solar but doesn’t show thermal outages. h/t
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What we know is ERCOT said on 7/10 that 12 GW of “dispatchable” was offline. On July 12-13 an additional 2.6GW of coal & gas ceased to operate, some after the conservation appeal was made. Ultimately, ~14-15GW of "dispatchable" couldn't be dispatched. #txlege 11/
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The conservation call, high prices & near outages on 7/13 were driven by old coal & gas plants owned by the same interests that are trying to get extra payments for those plants. You can read more about that here.
End/🧵#txlege #txenergy #energytwitter
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