Well I do know that ERCOT, like any other organization, sends out press releases. And since you're so adamant about the source being ERCOT themselves, there's one straight from their own website.
http://www.ercot.com/news/releases/show/225369
Of special note is the following, directly quoted from the same source:
"As of 9 a.m., approximately 46,000 MW of generation has been forced off the system during this extreme winter weather event. Of that, 28,000 MW is thermal and 18,000 MW is wind and solar."