Texas needs a bunch of solar, a bit of battery, that would cover peaks due to air conditioning. More insulation specified in residential building codes wouldn't hurt.
Once most Texans have EVs that charge with solar, and plug in at night and feed to the grid, the solution is even more obvious.
https://www.ercot.com/mktinfo/prices
edit: As I post it, there is a prime example of how people wave away transmission issues when talking about green energy. The wind farms on the coast near MX have a negative price (-11 to -33) while most of the state is sitting at ~90, and there is a problem in the west/central part of the state where its $180.
Solar can be placed almost anywhere in Texas, and in particular can be placed near where demand is expected. Transmission costs for it should be less than for large central power plants.
If land cost ever were a serious constraint on solar, solar would have become so cheap that it would already have destroyed all the competition.