1. Sixth Northwest Conservation & Electric Power Plan Proposed Heavy-duty Combustion Turbine Planning Assumptions Jeff King Northwest Power and Conservation Council Portland, OR July 17, 2008

2. 2 Reference plant Twin 85 MW (nominal) natural gas-fired gas turbine generators and ancillary equipment, control building and switchyard. Inlet air evaporative cooling. Low-NOx combustors and water injection for NOx control. Characteristics generally based on GE Frame 7EA.

3. July 17, 2008 3 Heavy-duty GT applications:  Energy generation  Cogeneration (requires heat recovery & integration equipment)  Regulating reserve (requires AGC)  Load-following (requires AGC)  Spinning reserve (requires AGC)  Non-spinning reserve  Replacement reserve  Voltage control (VAR support) (requires clutch)  Black start (requires auxilliary diesel generator)  Local emergency service Status: Commercially mature

4. July 17, 2008 4 H. D. GT operating characteristics I 5 th PlanProposed Base rating (net ISO MW, lifecycle average) 2 units @ 80 MW/unit 2 units @ 82 MW/unit ISO rating less 2% plant losses, less 2% degradation Rating at reference PNW locations PNW Westside (200’) PNW Eastside (700’) S. ID (3000’) E. MT (5500’) 0.99 0.97 0.90 0.82 Minimum load (% rated power)25%Same Ramp rate (%/hr)>100%SameCold start to min. load < 15 - 20 min Minimum run time (hr)1 hour< 1 hr Minimum down time (hr)1 hour< 1 hr

5. July 17, 2008 5 H. D. GT operating characteristics II 5 th PlanProposed Scheduled outage factor7% (26 day/yr average) ReviewAssume hours-dependent or starts-dependent maintenance in PNW? Need H.D. GT maintenance schedule to review. Equivalent forced outage rate7%??NERA is 3.7%. Review GADS Mean time between failures--???New parameter for PRM; will review GADS Mean time to repair51 hrSameGADS value ca: 2004. Will review GADS Heat rate (HHV, full load, lifecycle ave) 10,500 Btu/kWh11,800 Btu/kWhGTW nominal + 2.1% ave. lifecycle degradation. Vintage heat rate improvement- 0.5%/yr averageSame5% learning rate Service life30 yearsSame

6. July 17, 2008 6 H. D. GT Costs (2006 dollar values) 5 th PlanProposed Overnight construction cost$700/kW$430/kWSee following slides Vintage capital cost escalation-0.5%/yrDiscussion to follow Non-fuel Fixed O&M$7.00/kW/yrDiscussion to follow Exclusive of property taxes & insurance Non-fuel Variable O&M$4.60/MWhDiscussion to follow Startup Cost--Fuel for 20 min operation at min load Gas Turbine Handbook Shutdown Cost--Fuel for 30 min operation at min load Gas Turbine Handbook Transmission CostNoneSameAssumed to be located at load center Transmission LossesNoneSameAssumed to be located at load center

7. July 17, 2008 7 Heavy-duty GT construction cost analysis NPCC database contains reported construction cost for 7 WECC plants comprising 8 units, 2002-08 Normalized capital cost using MICROFIN Assume cost is vintaged as of beginning of construction (YOL - 1) 2006 dollar values "Overnight" construction + development cost Nominal ISO capacity Unit-weighted (we need an average cost value for a potential mix of plant configurations)

8. July 17, 2008 8 Normalized heavy-duty GT cost Proposed 2008 cost: $430/kW "Overnight", 2006$, 2009 service

9. July 17, 2008 9 Schedule, Cash Flows & Option phases Portfolio Risk model development phases > Development“Optional” Construction “Committed Construction” MilestonesFeasibility study through completion of permitting Notice to proceed to major equipment foundations complete Accept major equipment to commercial operation Time to complete18 mo12 mo(3) 6 mo Cash expended2 %93 %5 % Cost to suspend ($/kW)Negligible-- Cost to hold ($/kW/yr)$ 1.16 ($95,000/yr)-- Maximum hold time60 mo -- Cost of termination following suspension ($/kW) Negligible-- Cost of immediate termination ($/kW) Negligible--

10. July 17, 2008 10 Environmental 5 th PlanProposed Particulates--Values from recent permit? NPCC does not use & few if any requests SO2 -- ''NPCC does not use & few if any requests NOx -- ''NPCC does not use & few if any requests CO--''NPCC does not use & few if any requests Hydrocarbons/VOC--''NPCC does not use & few if any requests CO2 – Embedded--??? CO2 – Direct operation614 T/GWh690 T/GWhRevised heat rate CO2 – Indirect operation--???