Because they don't at close to the necessary scale. This site shows a projected July load profile for ERCOT (Texas) in 2035: https://www.spglobal.com/marketint

Because they don't at close to the necessary scale. This site shows a projected July load profile for ERCOT (Texas) in 2035: https://www.spglobal.com/marketintelligence/en/news-insights/research/battery-stampede-spurs-sunny-storage-economics-in-ercot https://www.spglobal.com/marketintelligence/en/news-insights... Note that Storage contributes for about four hours and at its peak comprises less than 7% of the total load serving capacity in the state. I'm not saying batteries don't exist and aren't useful, but the scale is very small at the moment. Too small to be a comprehensive way to balance out the low load factors of Wind and solar. (Which are also a useful but incomplete component of the overall electrical portfolio.)