PacifiCorp 2007 Integrated Resource Plan (May 30, 2007)

PacifiCorp – 2007 IRPChapter 7 – Modeling and Portfolio Selection ResultsFigure 7.39 – Stochastic Cost versus Risk Exposure for the $61 CO 2 Adder Case$61 CO2 Adder CaseCO2 Cap and Trade BasisRisk Exposure: Upper-TailStochastic Mean minus OverallMean PVRR (Billion $)70.0069.0068.0067.0066.0065.0064.0063.0062.00GHG Perf. Std.RA16RA15RA14RA17RA1361.00RA1960.0020.50 21.00 21.50 22.00 22.50 23.00Stochastic Mean PVRR (Billion $)As can be seen from the figures, the stochastic cost ranking of the GHG emissions performancestandard portfolio relative to the Group 2 risk analysis portfolios is sensitive to the CO 2 cost adderlevel. Under the $0/ton CO 2 adder case, the stochastic PVRR of the GHG emissions performancestandard portfolio is $662 million higher than that of the preferred portfolio. In contrast,under the $61/ton CO 2 adder case, the preferred portfolio stochastic PVRR is $406 millionhigher. When averaging stochastic PVRR results across the CO 2 adder cases, the GHG emissionsperformance standard portfolio falls within the middle of the pack.The GHG emissions performance standard portfolio has the highest risk among the Group 2 portfoliosfor all CO 2 adder scenarios. In comparison to the preferred portfolio, risk is about $3.6billion higher under the $0/ton CO 2 adder and $4.6 billion higher under the $61/ton CO 2 adder.Carbon Dioxide Emissions ResultsAs expected, the GHG emissions performance standard portfolio has a smaller CO 2 footprintthan the other risk analysis portfolios due to the lack of new coal plants. Relative to the preferredportfolio, the GHG emissions performance standard portfolio emits about 49 million fewer tonsof CO 2 on a cumulative basis from 2007 through 2026 when averaged across the five CO 2 addercases.The annual CO 2 emissions impact of the adder can be seen by comparing Figures 7.40 and 7.41,which show emissions under the $0 and $61/ton CO 2 adders, respectively. (Annual emissionquantities are reported as the contribution from retail sales; that is, net of wholesale sales.) Figure7.42 shows annual CO 2 emission trends as the average of the results for the six portfolios.217