2009 Scenario Reliability Assessment - NERC

Scenario Reliability Self-AssessmentsRegional Scenario Self-AssessmentsERCOT HighlightsA Scenario Case assessment was performed on the ERCOT Regionfor the 2009 NERC Long-Term Reliability Assessment. In thisScenario Case, incremental wind energy resources sufficient toprovide an additional 15 percent of the energy requirements in theERCOT Region, relative to the energy produced by wind resourcesin the Region during 2008, were assumed to be added by 2018.The Scenario Case was based upon studies completed by ERCOT in 2008 for the Public UtilityCommission of Texas (PUCT) as a part of the PUCT’s designation of Competitive RenewableEnergy Zones (CREZ). This Scenario Case assumes a total of 24,859 MW of wind generation isonline by 2018, whereas the Long-Term Reliability Assessment Reference Case assumes 10,558MW for 2018. This amount of installed wind capacity has the potential to produce approximately18 percent of the energy requirements of the 2018 load in the ERCOT Region.The Scenario Case assessment does not include a quantitative analysis of the system operationalrequirements, but qualitatively addresses some of the issues that would need to be addressed atthis level of wind penetration.In order to provide adequate transmission capacity for the wind generation resources included inthis Scenario Case, 300 miles of new 345 kV right-of-way and 360 miles of new HVdc right-ofwaywere added to the already-significant transmission additions included in the Long-TermReliability Assessment Reference Case.Incorporating the additional wind generation results in an adequate reserve margin through 2014,the same year identified in the Reference Case; however, this assessment did not evaluate anyother changes that might occur to the existing installed fleet of generation in economic responseto the additional wind generation.2009 Scenario Reliability Assessment Page 13