So much disinformation here.
Wind may be cheaper than coal but only for 4 to 6 hours AT NIGHT when demand is lowest. Still needs natural gas power backup so have to pay price of redundant power.
Coal has to be imported into Texas. Wind power needs no cost fuel imported from other states and so wind energy keeps all of its energy production inside the state (fuel, power plant, etc). I’m no fan of wind power but self reliant energy sources are what Texas is apparently seeking.
ERCOT, the Texas energy grid system, is self-contained and has no way of buying imported electricity but it can buy imported fuel to run in its power plants.
Texas is a Plains State and does not need wind and solar power to reduce air pollution from power plants as does, say, California, which is a Basin State where smog and pollution is trapped. So cleaner air is not the apparent objective in Texas, but self reliant energy sources apparently is.
Mutiple DC interconnects (Oklaunion, Monticello, and Eagle Pass) exist between ERCOT and other generating districts. How much power is moving between any two regions, which direction, one must do a deep dig.