Power plants located on the adjacent grids(such as the one you mention in east Texas) are allowed to supply power to the Texas grid if they are dedicated to the Texas grid. But plants located within the Texas grid and dedicated to the Texas grid cannot export power to the adjacent grids.
There has long been emergency connections between the Texas grid and the eastern, western, and Mexican grids.
A few years ago FERC ruled that the Texas grid could supply commercial power to the Mexican grid if none of that power could find its way onto the western grid and a commercial connection was established.
FERC has also ruled that Texas power could be exported to the eastern and western grid if that power is DC, but no DC transmission lines have been built. The planned Tres Amigas project and the four Clean Lines Energy Partners projects are DC.
All of these DC lines are to carry wind power generated in New Mexico, the panhandle, western OK, and SW Kansas eastward and westward.
Wind power in Texas began in 1997 when Enron bought Zond Corp and Texas established renewable standards in 1999. When Enron went under the Zond holdings were sold to GE.
It was the natural gas shortages in 2000/2001 and after Katrina that set off windmill building in Texas. Everyone remembers how Enron was screwing CA on natural gas. All that ended the political career of Guv Gray Davis in CA and Texas Sen Phil Gramm, who was replaced by John Cornyn
In 2005, the state lege would authorize the Texas CREZ Project with new windlines. In 2009 the Texas PUC would contract to build the new windlines, which were completed in 2014.
When the economy collapsed in 2008, the price of natural gas collapsed and hasn't recovered. Cheap natural gas is detrimental to windmills so the renewable energy tax credit is critical to windmills. Everybody in Congress is talking about Planned Parenthood in the budget negotiations underway, but none of them are talking about tax credits.
They will probably pass a budget extension next week then come back after the election, and the public is focused on Christmas, and pass the 2016 budget bill. With lots of goodies and pork.
