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Balancing Cost and Risk: The Treatment of Renewable Energy in Western Utility Resource Plans

Balancing Cost and Risk: The Treatment of Renewable Energy in Western Utility Resource Plans. Mark Bolinger Lawrence Berkeley National Laboratory (MABolinger@lbl.gov) NARUC Summer Meetings San Francisco, California August 1, 2006. Integrated Resource Planning (IRP).

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Balancing Cost and Risk: The Treatment of Renewable Energy in Western Utility Resource Plans

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  1. Balancing Cost and Risk:The Treatment of Renewable Energy in Western Utility Resource Plans Mark Bolinger Lawrence Berkeley National Laboratory (MABolinger@lbl.gov) NARUC Summer Meetings San Francisco, California August 1, 2006

  2. Integrated Resource Planning (IRP) • A formal process by which utilities analyze the costs, benefits, and risks of all resources available to them • Goal is to identify a portfolio of resources that meets future needs at lowest cost and/or risk • Re-emerging as an important planning process in states that are no longer exploring retail competition

  3. Planned RE Additions in Western Resource Plans Factors that Impact Planned RE Additions Candidate portfolio construction RE (wind power) cost and performance assumptions Treatment of natural gas price and carbon regulation risk How an IRP balances cost and risk Conclusions Overview of Presentation Objective: Summarize western utility resource plan treatment of renewable energy (RE), based on compilation and analysis of resource plan assumptions and methods

  4. Western Utility Resource Plans Included in Our Sample: ~50% of Western Load Pacific Gas & Electric (PG&E), Southern California Edison (SCE), San Diego Gas & Electric (SDG&E), Nevada Power, Sierra Pacific Resource plans from utilities subject to a Renewables Portfolio Standard (RPS) Resource plans in which no regulatory requirements compel RE additions Avista, Idaho Power, NorthWestern Energy (NWE)*, Portland General Electric (PGE), PacifiCorp, Puget Sound Energy (PSE), Public Service Company of Colorado (PSCo)* *PSCo’s and NWE’s most-recent resource plans preceded each state’s RPS

  5. Western Resource Plans Could Be a Major Source of Demand for New Renewables Non-RPS: Wind accounts for 92% of new RE capacity in 2014 RPS: Resources often unspecified New Renewables Capacity in 2014 (MW)

  6. Resource Plans Leading to Wind Contracts in Non-RPS States (though not always at the expected pace) • PGE: 75 MW Klondike II (2005); in 2006, purchased development rights to Biglow Canyon (126 MW in 2007, 350-450 MW total) • Idaho Power: 100 MW RFP reactivated in October 2005, 66 MW PPA just announced (company estimates 300 MW of wind – much of it smaller QF/PURPA contracts – on its system by end of 2007) • Pacificorp: 41 MW Combine Hills (2003); 64.5 MW Wolverine Creek (2005); 20 MW Schwendiman project (expected 2007); reissued RFP in 2006 for 100 MW by end of 2006, more in 2007 • NorthWestern: PPA with 135 MW Judith Gap (2005) • Avista: PPA of 35 MW from Stateline (2004); RFP for 35 aMW issued January 2006 • PSE: 150 MW Hopkins Ridge (2005) and 230 MW Wild Horse (2006)

  7. Planned Renewable Energy Additions Are Affected By… • How candidate portfolios are assembled and defined • What assumptions are made for the cost and performance of renewable energy • The degree to which (and how) electricity sector portfolio risks are considered • Natural gas price risk • Environmental compliance risk • How tradeoffs between the expected cost and risk of different portfolios are made

  8. Construction of Candidate Portfolios • Most plans create candidate portfolios by hand, making the composition of these portfolios all the more important • Many plans only include wind power in candidate portfolios, with other RE resources screened out at an earlier phase • Exogenous caps limit the contribution of RE in many IRPs • Resource plans in states with RPS obligations frequently do little to analyze the potential value of exceeding those obligations – i.e., the RPS serves as a cap, rather than floor • Resource plans in states without RPS obligations often exogenously cap the maximum amount of wind additions, to account for concerns over integration costs, transmission constraints, resource limits, etc.

  9. Utilities’ planned additions hit caps Exogenous Build Limits “Cap” the Amount of Wind Selected by Some Resource Plans PSE, NWE, PSCo, and Avista all chose portfolios with wind at the cap (Sierra Pacific and Nevada Power do not report RE additions by technology, but presumably would also hit their low caps)

  10. Assumptions About Cost/Performance of Wind Could Be Improved in Some Cases Busbar Costs:Capital and O&M assumptions are reasonable, but may need to be increased based on recent turbine prices Production Tax Credit: Undervalued by some resource plans, but many plans overstate the likelihood of renewal Transmission Costs:Plans often do not try to carefully evaluate transmission expansion needs Integration Costs:Some plans seem to over-estimate integration costs (or set low caps on wind), but improvements are dramatic in this area Capacity Value: Undervalued by many plans, but more recent plans more accurately evaluate capacity value

  11. Wind Power Cost and Performance Assumptions Vary Considerably Among the Plans Total cost for wind, including capital and O&M, PTC, integration, transmission, and RECs, ranges from $23/MWh to $59/MWh

  12. Some Resource Plan Integration Cost Assumptions Are High Compared to Recent Literature *PGE’s supplemental IRP estimates the cost of creating a flat, base-load block of power out of variable wind production, rather than simply the cost of integrating variable wind production. As such, its cost estimate is not directly comparable to the others. Some resource plans set strict limits on wind penetration due to concerns about integration costs: Avista 2003 (75 MW, 4% of peak load), Nevada Power (100 MW, 2% of peak load), and Sierra Pacific (50 MW, 3% of peak load)

  13. Some Resource Plan Capacity Value Assumptions Are Low Compared to Recent Literature • Though less dependable than other resources, wind provides some capacity value • ELCC is the most widely recognized method for determining capacity value • Most utility plans did not use ELCC to calculate capacity value • Many plans assumed lower capacity value than suggested in the literature

  14. Renewable Energy as a Risk Mitigation Tool Renewable energy may reduce at least two important risks… • Risk of high and volatile natural gas prices • Risk of more stringent environmental regulations Resource plans are becoming increasingly sophisticated in analyzing both risks, but further improvements are still needed

  15. Plans Increasingly Using Improved Tools to Evaluate Gas Price Risk • Current price expectations as revealed through NYMEX futures markets suggest that higher gas-price forecasts are warranted • IRPs using improved tools to evaluate uncertainty, but range of plausible prices may be greater than assumed in some cases

  16. Resource Plans Are Beginning to Evaluate Carbon Regulatory Risk • 7 of 12 considered risk in latest round of resource plans • Minimum of 10 of 12 plans will consider this risk in next round • Two outliers: Nevada Power, Sierra Pacific • For those utilities considering this risk, approaches vary • Carbon scenarios but with no probabilities attached • Carbon scenarios with probabilities attached • Included in base-case, sometimes with scenarios • Some utilities may not be evaluating a sufficiently broad range of possible carbon regulation scenarios • Risk of heightened environmental regulations, beyond carbon, are routinely ignored, but likely are of lesser importance to RE

  17. Methods and Approach to Carbon Risk Evaluation Vary

  18. Ultimately, resource plans must balance portfolios that have different cost and risk characteristics; how this tradeoff occurs can effect how well renewable energy fares in IRP Utilities have adopted different definitions of risk (most focusing on the upper tail of the distribution), and have taken different approaches to balancing expected cost and risk Each electricity customer may hold different risk preferences, and utilities have been given little guidance and have conducted little research on how to best make these tradeoffs Utilities virtually always use WACC to discount costs: we recommend scenario analysis be conducted on a wider range of discount rates, to reflect ratepayer and/or social perspectives Balancing Cost and Risk

  19. Initial Candidate Portfolios Finalist Candidate Portfolios Efficient Frontier Preferred Portfolio A B C D E F Alternative Scenarios Base-Case Scenario B D F Risk Stochastic / Monte Carlo Cost / Risk Tradeoff Scenario Analysis D Mean Cost Natural Gas Prices Electricity Prices Hydro Availability (Correlations) CO2 Regulations High/Low Gas Prices PTC Extension Wind Capacity Value Risk Paradigm Employed By: Avista, NorthWestern, PacifiCorp, PSE (2003) • Avista and NorthWestern assign subjective weights to cost and risk • PacifiCorp and PSE evaluate the cost/risk tradeoff more qualitatively • Some renewables portfolios “weeded out” before CO2 risk assessed!

  20. Initial Candidate Portfolios Finalist Candidate Portfolios Efficient Frontier Preferred Portfolio A B C D E F B D F Scenario 1 Stochastic / Monte Carlo Cost / Risk Tradeoff Risk Risk Qualitative Natural Gas Prices Electricity Prices Hydro Availability (Correlations) Mean Cost Mean Cost D A B C D E F Qualitative Scenario 2 A D E Stochastic / Monte Carlo Cost / Risk Tradeoff Risk Paradigm Employed By PSE (2005):Each Portfolio Subjected to All Risks!

  21. Initial Candidate Portfolios Efficient Frontier Preferred Portfolio A B C D E F All Scenarios Scenario Analysis Cost / Risk Tradeoff Risk D Mean Cost CO2 Regulations High/Low Gas Prices High/Low Power Prices PTC Extension Wind Capacity Value Risk Paradigm Employed By:PGE, PSCo, Nevada Power, Sierra Pacific • PGE assigned subjective probabilities to each scenario • PSCo, Nevada Power, and Sierra Pacific evaluate the cost/risk tradeoff more qualitatively

  22. Initial Candidate Portfolios Preferred Portfolio A B C D E F All Scenarios Scenario Analysis D CO2 Regulations High/Low Gas Prices High/Low Power Prices PTC Extension Wind Capacity Value Risk Paradigm Employed By: Idaho Power • Idaho Power assigned a subjective probability to each scenario • Preferred portfolio is that which has the lowest scenario-weighted expected cost, with no consideration given to the uncertainty of that cost

  23. Balancing Cost and Risk:Concerns for Renewable Energy • Plans often model RE primarily as wind power, assume a low capacity value, and/or apply low limits to wind penetration • As a result, many of the hand-crafted “renewables” portfolios are weighted heavily towards gas-fired generation, thereby exhibiting as much or more exposure to gas-price risk than other portfolios • Pushes resource selection towards coal more than renewable energy • Fuel price risk is often analyzed quantitatively early in the modeling process, while carbon risk is typically analyzed through scenario analysis later in the process, and in a way that has less effect on portfolio choice • Result is that RE portfolios are sometimes not considered low risk, and are sometimes “prematurely” weeded out at an early phase of the analysis, before carbon risk is considered

  24. Conclusions (1) IRP’s increasingly consider RE a serious resource option, and methodological improvements have been dramatic. But further improvements are still possible and needed: • Utilities in RPS states should consider evaluating RE as an option above and beyond the level required to satisfy RPS obligations • Resource planners may wish to explore a broader array of RE options • The value of the Federal PTC, and its risk of permanent expiration, could be more consistently addressed • Evaluation of integration and transmission costs, and capacity value, should continue to be refined (at higher wind penetration levels) • Exogenous caps on wind penetration should be removed and replaced with credible analysis of the cost of higher penetrations

  25. Conclusions (2) • Resource plans should evaluate a broad range of possible fuel costs, and subject a large number of candidate portfolios to such analysis • Environmental compliance risks could be more consistently and comprehensively evaluated • Each risk should have, as is appropriate, an opportunity to impact portfolio selection • Utilities and/or regulators should conduct research to evaluate ratepayer risk preferences • More consistent and comprehensive data presentation in resource plans would allow for far better external review • Wind cost assumptions may need to increase in future IRP’s, to reflect the tight turbine market • To ensure progress and results, ongoing benchmarking of actual procurements relative to resource plans is warranted

  26. Avista 2003 vs. 2005: What a Difference a Single Planning Cycle Can Make! Even with little change in assumed cost, “fixing” other related inputs can lead to vastly greater wind penetration

  27. For More Information... Download the full report from: http://eetd.lbl.gov/ea/ems/re-pubs.html Contact the authors: Mark Bolinger, MABolinger@lbl.gov, 603-795-4937 Ryan Wiser, RHWiser@lbl.gov, 510-486-5474

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