Analysis of Weatherization Measures Savings Methodology and Costs: Updated from 6 th Plan Regional Technical Forum June 1 st, 2010

Savings Methodology Existing vs. New Method 2 MethodExistingNew How Measures are Defined: Individually, by Htg Zone (i.e. “R0 to R11 Wall Insulation” saves x kWh/sqft for Heating Zone y) Individually, by Htg Zone (i.e. “R0 to R11 Wall Insulation” saves x kWh/sqft for Heating Zone y) How Savings DeterminedModeled Model Calibrated to Whole House Use?Yes (updated at Nov 2009 RTF mtg, see next slide) Measure-Specific Savings Calibrated to Impact Evaluations? No Modeling Software:SUNDAYSEEM Last Measure In Analysis Used?Yes Last Measure In Approach: 1. Determine ∆kWh/∆UA at the prototype’s cost-effective limit. 2. Apply ∆kWh/∆UA to each measure. Individually model savings for each measure, with remainder of house at cost-effective limit*. Number of Weather Stations: 5 (Portland, Seattle, Boise, Spokane, Missoula) 5 (Kalispell replaces Missoula) Number of Prototypes:3 (850 ft 2, 1350 ft 2, and 2184 ft 2 ) 3 (1350 ft 2, 2200 ft 2, and 2688 ft 2 ) Number of Heating Systems Modeled: 1 (Zonal) 3 (Zonal, FAF, Heat Pump) Separate Measures for each Heating System Type? No (applies to any htg. system) No (applies to any htg. system) * Note: Upcoming slide (4) shows how cost-effective weatherization limits will be determined.

Calibrating SEEM Model with Billing Analyses (from Nov 2009 RTF meeting) – Uses the following SEEM inputs for the heating temperature setpoints: Heat Pumps and Gas FAF – 70 degrees daytime – 64 degree night setback Electric FAF and Zonal Electric – 66 degrees day and night 3

Defining Roles and Clearing up Confusion from Last Meeting Under the existing method, the following were determined jointly by the Council (Tom) and by the RTF (Tom), without clearly defined roles – cost-effective insulation limits and – insulation measure savings In the new method, since potentially significant costs are at stake, roles are defined as follows: – Council: determine cost-effective weatherization limits – RTF: determine insulation measure savings What this means: – Council to generate and document measure optimization methodology that incorporates SEEM Who’s on Point: Tom and Ecotope, with input from Adam and RTF Level of effort = $$$; timeline = longer – RTF to generate and document measure savings methodology that incorporates SEEM Who’s on Point: Adam, with input from Tom, Ecotope and RTF Level of effort = $; timeline = shorter (Draft calculation spreadsheet for site built single family retrofit weatherization measures attached to today’s agenda) – Both systems feed each other, so collaboration is required. Note: Since Council portion won’t be completed soon enough for October PTR update, cost-effective weatherization limits will initially be estimated from 6 th Plan analysis, and updated when available. 4

Insulation Measure Costs Existing Method (from 5 th Plan) – Average of four sources PSE Reported Costs EWEB Reported Costs Pacific PUD Reported Costs 1996 Power Plan Costs New Method – Median of ETO Program Data (electric) May 2007 through July 2008 – Cost per ft 2 = [Median (ETO cost/ft 2 /∆R)] × [∆ R] 5

ETO Cost Data for Ceiling Insulation 6 Median: 2.3¢/ft 2 /∆R

ETO Cost Data for Floor Insulation 7 Median: 4.7¢/ft 2 /∆R

ETO Cost Data for Wall Insulation 8 Median: 9.1¢/ft 2 /∆R

Window Measure Costs Used ETO Program data for Multifamily – Multifamily costs expected to best convey the cost of the efficiency improvement – Single Family costs expected to be biased high due to additional “features” U-0.30 to U-0.25 assumed to be $2.00/ft 2 – Recommend change to $1.36/ft 2 per June 2009 RTF meeting decision Gary Curtis’ research on costs for a 0.30 window package versus

ETO Data 10

Cost Comparisons 11 Window Replacement (Not Shown) PTR: $ th Plan: $20.07

RTF Review Updated deemed savings will be shown to RTF when complete (goal: August RTF meeting) Any recommendations for changes to methods or data sources for savings or costs? 12