The answer is that it’s more important to Texans to adhere to its principals of independence and free market than it is to solve problems.
A lot of the problems of peak energy uses could be alleviated by connecting to the larger US grid to draw from regions whom don’t have as big spikes during those times, but that violates independence principals.
Texas’s laissez-faire approach to to the market reduces incentive to power companies to build for spikes. Basically, the grid is normally not at capacity. Building more capacity for spikes of demand isn’t profitable when you can’t sell that capacity most of the time (though note that a more connected grid would allow selling it over state lines). The spikes during peak demand allow operators to add usage charges and just profit from the scarcity. There’s no penalty for price gouging, and no incentive for companies to better.
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