Rolling Blackouts Highlight Troubles With Electric Grid In Rio Grande Valley
Courtesy of ERCOT
A map of projects to increase transmission capacity in the Rio Grande Valley.
It had been about three years since Texas experienced major rolling blackouts, but they happened this week in the Rio Grande Valley. The Electric Reliability Council of Texas (ERCOT), the group that manages nearly all of the Texas grid, says the blackouts are related to longstanding problems with the transmission system in the region.
Trouble started on Wednesday afternoon when two power plants suffered breakdowns. Fearing that high demand and low supply of electricity could damage the regional grid and cause an uncontrolled blackout, ERCOT called for “rotating outages” (industry speak for rolling blackouts) to keep some power on the lines.
Grid managers have known for some time the valley runs a higher risk of rolling blackouts. The reason is that the transmission system in the Valley is more isolated than other parts of Texas. It cannot easily bring in electricity from the rest of the ERCOT grid when needed.  That can cause blackouts in the Valley even when the rest of the grid is stable, according to ERCOT.
“The valley area has some significant limitations as far as how much power it can import into that region,” says Robbie Searcy, an ERCOT spokesperson. “Right now when there is a hot early fall afternoon and we have these sort of generation outages there is a risk to the transmission system in that area.”
