Short answer
Texas has its own grid mainly because its utilities kept their power within state lines, which kept them outside federal regulation of interstate electricity sales under the 1935 Federal Power Act [1]. The grid, run by ERCOT since 1970, remains outside the Federal Energy Regulatory Commission's jurisdiction and answers to the Public Utility Commission of Texas and the Legislature [1][2].
The federal-regulation reason
The Texas Tribune describes three main U.S. grids: the Eastern Interconnection, the Western Interconnection and Texas [1]. According to The Texas Tribune, Texas has its own grid largely to avoid federal regulation [1]. In 1935, the Federal Power Act gave the Federal Power Commission oversight of interstate electricity sales, and Texas utilities avoided those rules by not sending power across state lines [1].
The Federal Energy Regulatory Commission (FERC), which succeeded the Federal Power Commission, does not have jurisdiction over the ERCOT grid [1]. The Tribune also notes that Texas had its own coal, natural gas and oil, which made self-reliance easier [1].
How the grid developed
During World War II, several Texas utilities joined to form the Texas Interconnected System [1]. The Electric Reliability Council of Texas (ERCOT) was formed in 1970, after a major blackout in the Northeast in November 1965, to manage grid reliability according to national standards [1].
Texas's separation has been tested. In 1976, in an episode known as the "Midnight Connection," a Texas utility deliberately sent power to Oklahoma for a few hours, which set off a legal battle that could have brought Texas under federal regulators; it was resolved in favor of keeping Texas independent [1].
What ERCOT does today
ERCOT is a membership-based nonprofit that, according to its website as of October 2026, manages the flow of electric power to more than 27 million Texas customers, representing about 90% of the state's electric load [2]. It connects more than 55,000 miles of transmission lines and more than 1,460 generation units, including private use networks [2]. ERCOT is subject to oversight by the Public Utility Commission of Texas and the Texas Legislature [2]. The Texas Tribune describes ERCOT as managing the price of power and balancing supply and demand, with ERCOT and electric utilities answering to the Public Utility Commission, whose board is appointed by the governor [5].
How isolated it really is
ERCOT is not fully cut off. It is linked to the Eastern Interconnection and to Mexico's grid by direct-current ties, which a 2021 federal report says can import at most 1,220 megawatts in total [3]. The Tribune's 2011 explainer counted two ties to the eastern U.S. grid and three to Mexico, and said the ties do not trigger federal regulation for ERCOT [1].
The limited links mattered during the February 2021 winter storm. Federal staff found that on Feb. 15, 2021, east-to-west power flows approached 13,000 megawatts to help neighboring grid operators MISO and SPP meet demand, while ERCOT's imports were capped by its 1,220 megawatts of tie capacity [3].
ERCOT also does not cover all of Texas. El Paso is on the Western grid, most of the Panhandle and South Plains are served through the Southwest Power Pool, and the Beaumont area in Southeast Texas is part of the Midcontinent Independent System Operator grid [4].
Common questions
- Is Texas the only state with its own grid?
- Texas's ERCOT grid is one of the three main U.S. grids, alongside the Eastern and Western interconnections [1].
- Who regulates ERCOT?
- The Public Utility Commission of Texas and the Texas Legislature oversee ERCOT [2]. The grid is outside FERC's jurisdiction [1].
- Can Texas import electricity from other states?
- Only in limited amounts. ERCOT's ties to other grids can import a maximum of 1,220 megawatts, according to a 2021 federal report [3].
- Is all of Texas on the ERCOT grid?
- No. El Paso, most of the Panhandle and the Beaumont area are on other grids [4]. ERCOT serves about 90% of the state's electric load [2].
Sources
- Texplainer: Why does Texas have its own power grid?, The Texas Tribune, 2011-02-08
- About ERCOT, Electric Reliability Council of Texas, 2026
- The February 2021 Cold Weather Outages in Texas and the South Central United States, FERC, NERC and Regional Entity Staff, 2021-11
- Why Texas power outages didn't affect some parts of the state, The Texas Tribune, 2021-02-18
- How Texas' power grid works, The Texas Tribune, 2021-02-25