ERCOT: How Economic Dispatch is Done?
A Comparison between Bid- Based Bilateral Contract Model (Present)
Versus
Proposed Day Ahead Market Scheme of ERCOT (Future Nodal Scheme)
The Electric Reliability Council of Texas (ERCOT) formed in 1970, is one of eight Independent System Operators in North America and is the successor to the Texas Interconnected System (TIS). ERCOT is one of nine regional electric reliability councils under North American Electric Reliability Corporation (NERC) authority. ERCOT's offices are located in Austin and Taylor, Texas. The portion of the electric grid in the State of Texas that is under the administration of ERCOT was – and remains – essentially unconnected to electrical grids in other states and, in the absence of "electricity in interstate commerce," does not fall under federal regulation.
Fig 1: ERCOT coverage in Texas
The ERCOT region occupies the entire Texas Interconnection, which occupies nearly all of the state of Texas and caters to 85 % of Texas load & nearly 23 million customers. Unlike the other major NERC interconnections, the 40,530 circuit miles of high voltage transmission and energy market within the Texas Interconnection is operated by ERCOT as essentially a single power system instead of as a network of cooperating utility companies. It has more than 550 generating units which provide more than 74,000 megawatts (MW) capacity for peak demand
ERCOT Market size is about $ 34 billion and more than 1100 active market participants/entities in generation, distribution or use of wholesale electricity. In 1996, ERCOT initiated operations as a not-for-profit ISO, making it the first electric utility industry ISO in the United States.
Fig 2: Generation Capacity and Energy Usage of 2011 under ERCOT
FUNCTIONS/RESPONSIBILITIES OF ERCOT
The ERCOT ISO has the responsibilities of ensuring reliable power grid operations in the ERCOT region