Texas is unique in that it is served by multiple independent system operators. The vast majority of the state is in the **ERCOT** (Electric Reliability Council of Texas) grid, but significant portions are served by the **SPP** (Southwest Power Pool).
ERCOT: The Independent Island
ERCOT manages the flow of electric power for 90% of Texas. It is not synchronously connected to other U.S. grids, which allows it to operate largely under Texas-only regulation by the PUCT.
SPP: Regional Interconnectivity
SPP operates across multiple central states. Texas Panhandle and Northeast Texas residents in SPP zones are part of a larger multi-state grid market, often resulting in different rate structures than those in ERCOT.
Modeling Context
GetSunScore identifies your grid market based on your TDU territory. This determines whether we apply ERCOT competitive rate benchmarks or SPP cost-of-service assumptions in our solar savings engine.
Grid Market FAQ
Most of Texas (roughly 90% associated with deregulated zones like Oncor and CenterPoint) is served by ERCOT. The SPP (Southwest Power Pool) serves portions of the Texas Panhandle and Northeast Texas. Your utility bill will specify your TDU.
Yes. ERCOT is a deregulated retail market with competitive buyback plans, while SPP areas in Texas often operate under more traditional, vertically integrated utility structures with different export compensation tariffs.