Dorm 15 said:
This may sound like a strange question at this time but what happens on the Texas grid when supply exceeds demand?
Happens all the time at night in the mild months. ERCOT prices go negative (pay people to take your power). Practically, it means that plants reduce load and shutdown. Coal and gas first since they can save fuel costs. Windmills don't mind it too much since they still get a production tax credit (unless that expired?)
There is almost always more reserve supply available than demand. There are entire power plants -peaking units - that only go online during high demand.