Thread by @bcshaffer

Quick (chart) thread on Ercot generation during the power outages.

Can't recall who made this plot, but it's excellent (albeit without y-axes!!).

Changes over time are informative, but not the whole story.

In terms of how each fuel type performed, we not only want to judge its absolute production, but also relative to what was expected of it.

Ercot did a Winter 2020/21 resource adequacy assessment in November and came up with the following:
67GW thermal+hydro
7GW wind
0.3GW solar

They also ran "risk scenarios", essentially more thermal outages or less wind. Interestingly they didn't run the extreme forced thermal outage *AND* the extreme low wind scenario together!

So we can plot the performance of each generation fuel type in Texas both in absolute hourly MW, and relative to their expected (black dashed line) and extreme case capacity (red dashed line).

Note: I'm using a 4-day period for the outages, shown in grey.

We can look closer at each fuel type and see how they performed relative to their *expected* and *extreme case* scenarios. Note: I'm allocating thermal outage risk scenarios proportionally by capacity.

Here's coal. Underperformed even the extreme scenario by 28%.

Here's natural gas. Also significant underperformance relative to expected and extreme. In terms of MW magnitude of deviation, NG was the largest.

The absolute response of NG leading up to the power outages is great, but was expected and counted on.

Here's nuclear. Bravo nuclear. With one reactor tripping it was inline with the extreme scenario.

Here's wind. Expected capacity was 7GW. Average 3800MW through the event. Grossly underperformed expected, but significantly beat Ercot's SARA extreme case scenario (1791MW).

Finally, solar. Wasn't counted on to produce much and more than doubled that. Part of the issue here is likely unexpected growth in solar installations. Solar was perhaps the one bright spot (no pun intended) in the generation landscape last week.

Darn it. There's always a typo. Or in my case a completely wrong chart.

Here's the *correct* coal chart. Many thanks @whgorman for spotting the error.