PacifiCorp 2007 Integrated Resource Plan (May 30, 2007)

PacifiCorp – 2007 IRPChapter 8 – Action Plansion of PacifiCorp’s benchmark resources, represents a logical and efficient strategy to addressthis requirement.To formulate and analyze different resource acquisition paths, the RFP modeling process includestwo deterministic scenario analysis steps in which bid resources, including PacifiCorpbenchmark resources, are evaluated with the Capacity Expansion Module under a range of scenarioassumptions. The scenarios capture a combination of alternative electricity/gas prices, CO 2cost adders, and planning reserve margins.The first scenario analysis step involves running the CEM with the full set of short-listed bidresources to assist in screening the resources. The second scenario analysis step occurs after stochasticsimulation has been used to select bid resource finalists. The portfolio of bid resourcefinalists is subjected to another round of CEM runs using the same scenario set applied to initiallyscreen the bid resources. In contrast to the first scenario analysis step, the bid resources arefixed, and CEM use is limited to just determining the dispatch solution and PVRR under differenteconomic conditions. This path analysis step is intended to help assure the company that thebid resource finalists are robust with respect to cost and cost variability under alternative economicand planning assumptions.234