> ... but having so much capacity invested in unreliable wind generation was a very significant contributor to the blackouts that should not be ignored.

The word 'unreliable' is ambiguous here -- clearly world+dog understands that power generated by wind is highly variable, and ERCOT (as for any ISO, and similar orgs in other countries) maintains and improves their forecasts around this variability.

This is factored into the overall grid provisioning and maintenance of power to consumers. It's why I asked about the effect of this variability outside of major cold events. Evidently not so much?

So, using the word 'unreliable' in a way that sounds like wind turbines can't be trusted seems disingenuous, since there's no surprises with the way they operate, and the variability in the power they can generate.

Your comment that billions should have been invested in anything except wind, and this would have guaranteed significantly more electricity available - isn't supported by the facts. Nuclear, gas, and coal all failed in various but predictable ways.

So you're kind of conceding that winterisation would have helped, but only in the context of fewer wind turbines being taken out. The fact coal, gas, and nuclear failed, because they hadn't been properly protected against cold weather, you seem to be discounting.

I haven't stared at the ERCOT numbers, and am disinclined to do so -- the fact that much of the state was without power for several days, and early reports suggested the grid was some minutes away from catastrophic cascading failure, suggests to me that concise numbers aren't the important thing here.

What's clear is that despite the 2011 heads-up, and the audit two years ago that highlighted the continued lack of preparedness, it was way more than the predictable freezing of some wind turbines. The history and political motivation for this highly isolated ISO further highlights the problems of poor planning and poor regulation. Were they not so intentionally disconnected, power could have easily been sourced from elsewhere in the country.

I did find an interesting 'actual number' that their lack of maintenance for their wind turbines was a major contributory factor:

"Though frozen wind turbines were a contributing factor, wind shutdowns accounted for less than 13% of the outages, Dan Woodfin, senior director of system operations for ERCOT, told Bloomberg." [0]

Further in that article:

"According to a report from ERCOT, solar accounts for only 3.8% of the state's power capacity throughout the year. Wind energy accounts for 10% of Texas's winter energy capacity and throughout the entire year it is able to provide 24.8%, the second-largest source of energy in the state under natural gas, which accounts for 51%."

Which suggests your 25% figure is misleading, as that's a yearly average - it's 10% (about the same as nuclear) during that time of year.

[0] https://edition.cnn.com/2021/02/19/politics/texas-energy-out...