2009 Scenario Reliability Assessment - NERC

Scenario Reliability Self-AssessmentsThe power flow analysis and simulations for 8,000 MW of wind were only conducted for thestudy year 2018. The purpose of the study is to determine the areas of the transmission systemand the extent that wind plants would be constrained as well as how system variability would beimpacted by wind.DemandThe NYISO used its August 2008 demand forecast for the Scenario Case. It includes the impactof new Energy Efficiency/conservation initiatives being implemented by the State of New Yorkas part of the Energy Efficiency Portfolio Standard. The economic assumptions include highereconomic growth than in the 2009 Long-Term Reliability Assessment load forecast, which wasprepared after the current recession commenced. The weather assumptions are the same as thoseused in the 2009 Long-Term Reliability Assessment load forecast.The 2009 summer peak demand reported in the 2009 Long-Term Reliability Assessment wasforecasted to be 33,452 MW. For the same year, the scenario's summer peak demand forecastwas 34,059 MW. The 2018 summer peak forecast in the 2009 Long-Term Reliability Assessmentis 35,450 MW, a growth of 1,998 MW over nine years. The scenario’s peak forecast for the sameyear is 35,658 MW, a growth of 1,599 MW. The annual average growth rate summer peakdemand for the 2009 Long-Term Reliability Assessment is 0.65 percent. For the same period, thesummer peak demand growth rate of the scenario is 0.51 percent.GenerationCapacity resource data in the base Scenario Case are from the 2009 RNA report. These includegeneration resources listed in the 2008 Gold Book, 2,084 MW of Special Case Resources, andthose resources that met specific screening requirements for inclusion while the Reference Caseused the 2009 Gold Book data Also, the Reference Case includes assumptions for FutureCapacity additions and Conceptual additions that were different from the Scenario studyconditions. The resulting differences total a reduction of 1,333 MW for the Scenario Case studyyear of 2018 vs. the Reference Case. Capacity resources of 42,536 MW were included in theScenario Case versus the 43,869 MW reported in the Reference Case.For the Scenario Case study, 8,000 MW of wind resources were added, all in the year 2018. Thefigure below presents the simulated output of the 8,000 MW of wind assuming no transmissionconstraints. The trend component, or green line is the 720 hourly moving average or monthlymoving average. It demonstrates how the wind plant output varies seasonably.The 8,000 MW of wind included in this study represents nearly all of the wind projects listed inthe NYISO Interconnection Queue as of the ignition of the study. 73 These projects have not metany milestones other than having submitted a request to be interconnected to the NYISOtransmission system.73 The interconnection process is a formal process defined by NYISO’s tariffs by which the NYISO evaluatestransmission and generation projects, submitted by Market Participants, developers, and other qualifiedorganizations to determine their impact on system reliability.Page 942009 Scenario Reliability Assessment