Sixth Northwest Conservation & Electric Power Plan Proposed Aeroderivative Combustion Turbine Planning Assumptions Jeff King Northwest Power and Conservation Council Portland, OR July 17, 2008

2 Reference plant Twin 47 MW (nominal) natural gas-fired gas turbine generators and ancillary equipment, control building and switchyard. Inlet air evaporative cooling. Dry low- emission combustors and SCR for NOx control and CO oxidizing catalyst for CO and VOC control. Located in utility service territory near load center. Characteristics generally based on GE LM6000PD Sprint.

July 17, Aeroderivative 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

July 17, Aeroderivative GT operating characteristics I 5 th PlanProposed Base rating (net ISO MW, lifecycle average) 2 46 MW/unit 2 45 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’) Minimum load (% rated power)25%Same Ramp rate (%/hr)>100%SameCold start to min. load < 10 min Minimum run time (hr)1 hour< 1 hr Minimum down time (hr)1 hour< 1 hr

July 17, Aeroderivative GT operating characteristics II 5 th PlanProposed Scheduled outage factor3.6% (10 days/yr ave) SameGE maintenance schedule:  Annual – 7 d  6 yr Hot gas path – 10 d  12 yr Major - 28 d Equivalent forced outage rate3.6%/10%??NERA is 3.7%. Review GADS Mean time between failures--528 hrGADS GT value ca: Will review GADS Mean time to repair80 hoursSameGADS GT value ca: Will review GADS Heat rate (HHV, full load, lifecycle ave) 9960 Btu/kWhSame1% degradation during hot gas path maintenance interval; 50% retoration; 100 % restoration at Major Vintage heat rate improvement- 0.5%/yr averageSame5% learning rate Service life30 yearsSame

July 17, Aeroderivative GT costs (2006 dollar values) 5 th PlanProposed Overnight construction cost$700/kW$860/kW2008 NTP/2009 service Vintage capital cost escalation-0.5%/yrSee subsequent slides Non-fuel Fixed O&M$9.30/kW/yrGRAC discussion Exclusive of property taxes & insurance Non-fuel Variable O&M$9.30/MWhGRAC discussion Startup Cost--Fuel for 10 min operation at min load 110 MMBtu/start, w/SCR (NERA) Shutdown Cost--Fuel for 5 min operation at min load Transmission CostNoneSameAssumed load center location Transmission LossesNoneSameAssumed load center location

July 17, Aeroderivative GT construction cost analysis NPCC database contains reported construction cost for 17 WECC plants comprising 54 units, Purged plants w/more than four units. Purged SF & SCE peakers. Remaining: 9 plants, units ea., 22 units total Normalize capital costs using MICROFIN Assume cost is vintaged as of beginning of construction (YOL - 1) 2006 dollar values "Overnight" construction + development cost Nominal ISO capacity Unit (capacity) -weighted (we need an average cost value for a potential mix of plant configurations)

July 17, Normalized aeroderivative GT cost Proposed 2008 cost: $860/kW "Overnight", 2006$, 2009 service

July 17, Our preliminary thinking on forecast construction cost escalation Escalation continues at declining rate through 2009; levels off Real costs decline to ~ 130% of 2004 values Recent cost escalation 2015 > Resumption of historical real cost reduction

July 17, 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--

July 17, Environmental 5 th PlanProposed Particulates0.09 T/GWhValues from recent permit? NPCC does not use & few if any requests SO T/GWh ''NPCC does not use & few if any requests NOx T/GWh ''NPCC does not use & few if any requests CO T/GWh ''NPCC does not use & few if any requests Hydrocarbons/VOC0.08 T/GWh''NPCC does not use & few if any requests CO2 – Embedded--??? CO2 – Direct operation582 T/GWhSame117 lb CO2/MMBtu NG CO2 – Indirect operation--???