Constraints and Needs Transmission Report
The Electric Reliability Council of Texas’s annual transmission planning report includes $3 billion in proposed projects for the next five years, expected to add 2,538 miles of transmission lines and additional autotransformer capacity.
The 2007 Electric System Constraints and Needs report, filed in late December with the Public Utility Commission (PUC), identifies and analyzes existing and potential constraints in the transmission system that could pose reliability concerns or increase costs to the electric power market, and ultimately, to Texas consumers.
The major 345-kV transmission lines planned include:
- 88 circuit miles, Bell County East – Twin Oaks, operational 2012
- 198 circuit miles, Red Creek – Killeen line, operational 2012
- 38 circuit miles, Oklaunion – Bowman line, operational 2012
- 22 circuit miles, Nacogdoches – Lufkin line, operational 2012
- 103 circuit miles, Clear Spring – Salado, operational 2010/2011
- 110 circuit miles, San Miquel – Laredo, operational 2010
- 7 circuit miles, West Levee – Norwood (Dallas/Fort Worth), operational 2009.
The report also analyzes costs to resolve zonal congestion (between zones) and intrazonal congestion (local). After several years of decrease, transmission congestion costs appear to be level between 2006 and 2007, the report found, but noted that overall costs may trend higher until planned lines are added.
The continued rapid increase in the installation of new wind generation in West Texas is expected to result in transmission congestion until new bulk transmission lines are added between West Texas and the rest of the ERCOT system.
Two new 345-kV transmission lines and a switching station are included in the proposed projects for the West zone to accommodate approximately 6,500 megawatts (MW) of wind generation that is installed or has completed an interconnection agreement. However, the West zone upgrades may be superseded by the transmission lines ordered as a result of the Competitive Renewable Energy Zone (CREZ) process underway at the PUC. The PUC is expected to designate the final CREZ transmission projects around mid-2008.
Since 2005, ERCOT transmission service providers have completed over 2,500 circuit miles of transmission lines and approximately 28,000 MVA of autotransformer capacity, with an estimated capital cost of over $2.2 billion.
ERCOT is a membership-based 501(c)(4) nonprofit corporation, governed by a board of directors and subject to oversight by the Public Utility Commission of Texas and the Texas Legislature. Its members include consumers, cooperatives, generators, power marketers, retail electric providers, investor-owned electric utilities, transmission and distribution providers and municipally owned electric utilities.