I'm not sure, but my experiences with rolling blackouts in northern CA haven't been about grid capacity in the last 15 or so years. All the rolling blackouts I've seen were to prevent fires from above-ground power lines, which caused massive fires, death and destructive when conditions were dry and winds were high. High winds and dry vegetion + above ground power lines = rolling blackout. Power plant batteries would have nothing to do with such rolling blackouts. Other parts of the country, e.g., Texas, seem to have rolling blackouts because of dificient capacity at times.

Here is a Scientific American article explaining that annual flu death figures are estimated, not counted. Actual counted flu deaths are much lower. Apples to apples comparison is actual counted flu deaths to actual counted covid19 deaths OR estimated flu deaths, which is the publishe cdc number, to estimated covid19 death, which is a much larger number than actual counted covid19 deaths. https://blogs.scientificameric... quote of article In the last six flu seasons, the CDC/âs reported number of actual confirmed flu deathsâ"that is, counting flu deaths the way we are currently counting deaths from the coronavirusâ"has ranged from 3,448 to 15,620, which far lower than the numbers commonly repeated by public officials and even public health experts.