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Estimating the Generation Resource Mix of Electricity Imports to California – Energy Commission Staff Paper. California Energy Commission and Public Utilities Commission Workshop on Reporting and Tracking Greenhouse Gas Emissions for a Load-Based Cap April 12 and 13, 2007 Al Alvarado

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  1. Estimating the Generation Resource Mix of Electricity Imports to California – Energy Commission Staff Paper California Energy Commission and Public Utilities CommissionWorkshop on Reporting and Tracking Greenhouse Gas Emissions for a Load-Based Cap April 12 and 13, 2007 Al Alvarado Electricity Analysis Office California Energy Commission aalvarad@energy.state.ca.us Staff Paper - April 12,2007

  2. Presentation Overview • Purpose of Resource Mix Analysis • Role of Electricity Imports • Average Regional Methodology • Alternative Approach to Estimate Resource Mix Staff Paper - April 12,2007

  3. Goals of Resource Mix Analysis • Increase attribution of specific purchases and ownership • Estimate unspecified purchases into what is bought & sold in the market • Advance links between statewide and LSE accounting • Incremental improvement of current estimate, while shifting emphasis to new reporting and tracking Staff Paper - April 12,2007

  4. Types of Electricity Imports • Ownership shares of generation located out-of-state • Contracts and other entitlements • Purchases to satisfy customer obligations • Purchases to cover unexpected short-term variations (i.e. forced outages) • Economy Purchases • Wheeling through CA Staff Paper - April 12,2007

  5. Average Methodology Used for GHG Emissions Imports Inventory 2000 to present GHG emission estimates apply the average generation mix in each region Current estimates reported in: Net System Power Report 2006 Greenhouse Emissions Inventory Report Staff Paper - April 12,2007

  6. Limitations of Averaging Approach • Does not account for specific ownership or power purchase agreements • Ignores system constraints • Does not capture when and what types of electricity is purchased • Assumes California is purchasing the same mix as region’s native load • Does not account for other state’s priority preferences Staff Paper - April 12,2007

  7. Revised Approach to Estimate Imports Resource Mix • First identify ownership generation • Identify long-term power purchase contracts and entitlements (i.e. Hoover) • Remaining balance are considered unspecified system imports Staff Paper - April 12,2007

  8. Specified and Unspecified Imports by Region for 2005 Staff Paper - April 12,2007

  9. Estimating Sources of Unspecified Imports • Separate Northwest and Southwest regions – different generation profiles • Coordination with other western efforts • Initial study uses marginal generation analysis for Southwest mix • Initial study uses marginal generation analysis and sales assessment for Northwest Staff Paper - April 12,2007

  10. Rationale for Marginal Generation Analysis Used for Electricity System Imports • Utilities and generators typically use their cheapest electricity supplies to meet customer obligations • Baseload generation is usually the lower cost resource, mostly owned by utilities • Remaining surplus are generally the marginal generation resources • Electricity from marginal generation will be sold if there is a market Staff Paper - April 12,2007

  11. Southwest Study • System simulations to respond to stakeholder questions on marginal resource assumptions • Test to see what generation is re-dispatched with reduced imports • Transfer capability reduced to amount needed for specified resources • Transmission constraints create 53-59 GWH coal-generation drop (0.1%) • Natural gas generation increase in CA & Southern Nevada, declines in rest of SW Staff Paper - April 12,2007

  12. Table 3 - 2005 Southwest Electricity Imports Resource Mix (GWh) Staff Paper - April 12,2007

  13. Unspecified Imports from Northwest • NW predominately hydroelectric system • High correlation between NW water conditions and California system imports • Identify types of sellers to California • Attribute generation mix to each seller: • IOU, POU & Other = WA/OR disclosures • Canada = Hydro • IPP & Marketers = 50% Hydro, 46% Gas, 4% Coal Staff Paper - April 12,2007

  14. Table 5 - 2005 Northwest Electricity Imports Resource Mix (GWh) Staff Paper - April 12,2007

  15. Comparison of the 2005 Total Statewide Imports Resource Mix Using the Revised and Average Estimation Methods Staff Paper - April 12,2007

  16. Inter-State Coordination • Working with Washington and Oregon energy staff • Better understand purpose and tracking methodologies between states • A coordinated regional tracking system is needed • Avoid double-counting and shifting emission attributions • LSE transaction choices that lead to actual emission reduction Staff Paper - April 12,2007

  17. Partial Data Available to Track Imports • Metered gross and net power flows between 3 CA and out-of-state control area operators • Electricity generation and fuel use by power plant • Power Source Disclosure for 70% of CA • FERC and EIA Reporting • Limited information on the generation source of the electricity imports • Additional types of data needed to advance ability to track transactions Staff Paper - April 12,2007

  18. Conclusion • The revised methodology provides a more detailed characterization than previous approaches • More LSE purchase data would refine the resource mix estimates • This is an interim approach for historical and near-term tracking • More policy analysis and inter-state discussion needed prior to finalizing methodology Staff Paper - April 12,2007

  19. Background Slides Staff Paper - April 12,2007

  20. Net Electricity Imports(MWh) Staff Paper - April 12,2007

  21. Staff Paper - April 12,2007

  22. Net System Power ReportImports from PNW and SW (GWh) Staff Paper - April 12,2007

  23. 2005 Net Electricity Imports (GWhs) Source: California Energy Commission Staff Paper - April 12,2007

  24. Staff Paper - April 12,2007

  25. California Utility Ownership Sharesof Generation Facilities Located Out-of-State(Dependable Capacity MW) Staff Paper - April 12,2007

  26. Generation from California Utility Ownership Shares(Gigawatt hours per year) Staff Paper - April 12,2007

  27. CA Utility Ownership of Out-of-State Plants (Summer Capacity MW) * IPP figures represent contracted capacity.** Source: Global Energy Decisions Staff Paper - April 12,2007

  28. Correlation Between PNW Hydro-Generation and Electricity Imports to California (1993-2005) Staff Paper - April 12,2007

  29. 2005 Statewide Electricity Imports Resource Mix (GWh) Staff Paper - April 12,2007

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