Home Performance with ENERGY STAR

Transcription

1 2012 Home Performance with ENERGY STAR Evaluation of Austin Energy s Home Performance with ENERGY STAR (HPwES) Program September 2012 Prepared by:

2 Table of Contents TABLE OF CONTENTS I 1 EXECUTIVE SUMMARY FINDINGS IMPACT EVALUATION PROCESS EVALUATION RECOMMENDATIONS IMPACT EVALUATION PROCESS EVALUATION 5 2 PROGRAM OVERVIEW GOALS AND OBJECTIVE REBATE PROGRAM MEASURES PROGRAM STATISTICS AND MEASURES IMPLEMENTED 9 3 EVALUATION OVERVIEW IMPACT EVALUATION OVERVIEW ENERGY SAVINGS MODEL COST EFFECTIVENESS MODELS BILLING ANALYSIS PROCESS EVALUATION OVERVIEW REVIEW OF PROGRAM MATERIALS PROGRAM STAFF INTERVIEWS REVIEW OF RELEVANT PROGRAMS AND BEST PRACTICES 21 4 IMPACT EVALUATION ENERGY EFFICIENCY IMPROVEMENTS INFILTRATION REDUCTION ADDITIONAL ATTIC INSULATION COOLING SYSTEM IMPROVEMENTS CENTRAL AC (NATURAL GAS HOMES) 23 i GDS Associates, Inc.

3 4.1.4 HVAC IMPROVEMENTS ASHP (ELECTRIC HOMES) DOMESTIC HOT WATER IMPROVEMENT LIGHTING AND APPLIANCE REPLACEMENTS LOW FLOW DEVICES PROGRAMMABLE THERMOSTATS DISTRIBUTION SYSTEM IMPROVEMENT WINDOW IMPROVEMENTS INDIVIDUAL MEASURE SAVINGS MEASURE PACKAGE SAVINGS COST EFFECTIVE ENERGY EFFICIENCY IMPROVEMENTS BILLING ANALYSIS RESULTS PRIORITIZATION STRATEGIES 52 5 PROCESS EVALUATION GOALS AND OBJECTIVES FINDINGS RECOMMENDATIONS OPERATION AND DELIVERY OVERVIEW OF PROGRAM OPERATION HOME PERFORMANCE PROTOCOLS CONTRACTOR NETWORK QUALITY ASSURANCE RECOMMENDATIONS COORDINATION AND COMMUNICATION FINDINGS RECOMMENDATIONS MARKETING AND CUSTOMER EDUCATION FINDINGS RECOMMENDATIONS PARTICIPATION AND BARRIERS TO PARTICIPATION FINDINGS RECOMMENDATIONS CUSTOMER DECISION MAKING AND PROGRAM INFLUENCE FINDINGS RECOMMENDATIONS INCENTIVE STRUCTURE 74 ii GDS Associates, Inc.

4 5.7.1 FINDINGS RECOMMENDATIONS DATABASE AND TRACKING SYSTEMS FINDINGS RECOMMENDATIONS EFFECTIVE METHODS FOR ACHIEVING MAXIMUM PARTICIPATION AND SAVINGS BEST PRACTICES FOR HOME PERFORMANCE WITH ENERGY STAR PROGRAMS METHODS FOR MAXIMIZING PROGRAM PARTICIPATION AND ENERGY SAVINGS EVALUATION, MEASUREMENT AND VERIFICATION METHODS ENERGY EFFICIENCY TECHNOLOGIES TO CONSIDER 89 6 REVIEW OF REGIONAL HOME PERFORMANCE PROGRAM, CUSTOMER INCENTIVE PROGRAMS, INDUSTRY STUDIES AND OTHER RESEARCH FINDINGS RECOMMENDATIONS EVALUATION FINDINGS AND RECOMMENDATIONS IMPACT EVALUATION SUMMARY OF FINDINGS SUMMARY OF ASSESSMENT AND RECOMMENDATIONS PROCESS EVALUATION BEST PRACTICES LESSONS LEARNED SUMMARY OF ASSESSMENT AND RECOMMENDATIONS 121 APPENDIX A. TREAT MODEL ASSUMPTIONS FOR PROTOTYPE HOMES 128 APPENDIX B. SAMPLE EVALUATION MEASUREMENT AND VERIFICATION PLAN 140 APPENDIX C. OTHER HOME PERFORMANCE PROGRAM MANAGER SURVEYS 152 APPENDIX D. BEST PRACTICE REVIEW FINDINGS 163 ARIZONA S HOME PERFORMANCE WITH ENERGY STAR PROGRAM 164 ONCOR S HOME PERFORMANCE WITH ENERGY STAR PROGRAM 167 iii GDS Associates, Inc.

5 AEP PUBLIC SERVICE COMPANY OF OKLAHOMA HOME PERFORMANCE WITH ENERGY STAR PROGRAM 169 THE BUILDING PERFORMANCE INSTITUTE 173 HOME PERFORMANCE RESOURCE CENTER 176 THE NEW YORK HOME PERFORMANCE WITH ENERGY STAR PROGRAM 177 THE NEW JERSEY HOME PERFORMANCE WITH ENERGY STAR PROGRAM 178 RESIDENTIAL HVAC QUALITY INSTALLATION & MAINTENANCE 179 HOMEOWNER PERSPECTIVES AND MARKETING 181 MCKINSEY GLOBAL ENERGY AND MATERIALS U.S. ENERGY EFFICIENCY REPORT 186 U.S. EPA REVIEW OF APPLIANCE RECYCLING PROGRAMS 192 EPA ENERGY MANAGEMENT GUIDELINES AND BENCHMARKING BEST PRACTICES 194 iv GDS Associates, Inc.

6 1 Executive Summary GDS conducted an impact and process evaluation of Austin Energy s Home Performance with ENERGY STAR (HPwES) program. The following tasks were completed by GDS and the findings and recommendations from these activities are presented in this evaluation report. Task 1: Analyze Austin Energy s HPwES Program data to identify peak power, energy and dollar savings (kw, kwh, $), program costs and cost effectiveness using appropriate cost tests. Task 2: Evaluate Austin Energy s HPwES Program prioritization strategy to determine highest program energy savings potential. Task 3: Evaluate Austin Energy s HPwES Program elements/process, NOT including program marketing and outreach campaigns, contractor assignments and role of third party for scope of work assignments and inspection duties. Task 4: Identify lessons learned and best practices from Austin Energy s HPwES Program. Task 5: Conduct review of other utility HPwES and customer incentive programs, industry studies and other research to identify potential application to Austin Energy s HPwES Program. Task 6: Identify the most effective methods and measures for achieving maximum participation and efficiency rates, measurement and verification protocols, identification of energy efficiency technologies that might be introduced and that are not currently part of the program. Task 7: Provide recommendations for an Austin Energy residential conservation program that maximizes energy savings while minimizing the cost to the utility. 1.1 Findings The following sections contain a summary of GDS findings regarding the evaluation of Austin Energy s HPwES Program Impact Evaluation AE s rebated measures and packages of measures were evaluated using energy savings and cost effectiveness modeling. The measures were evaluated as individual and packaged measures in two prototypical baseline homes evaluated for (a) an all electric mechanical systems and for (b) a natural gas fired heating and domestic hot water mechanical system. The improvement measures are considered retrofit measures; therefore the total cost is used in the analysis because the savings are based on replacement of existing equipment. The following rebated individual measures were evaluated to be cost effective using the Total Resource Cost (TRC) test: 1 GDS Associates, Inc.

7 The addition of attic insulation from R11 to R26 The addition of attic insulation from R11 to R29 The addition of attic insulation from R11 to R38 The repair of leaking duct work and duct sealing Solar Window Film The Heat Pump Domestic Hot Water (DHW) Heater Air infiltration measures in the electrically heated homes 14 SEER Central Air Conditioners in the smaller Home A The following rebated individual measures failed the TRC cost test: Air infiltration measures in the natural gas heated homes Ground Source Heat Pumps Air Source Heat Pumps SEER 15, SEER 16 and SEER 17 Central Air Conditioners SEER 14 Central Air Conditioners in Home B (the larger home) The individual measures were combined into packages and the interactive savings were calculated for each package. Austin Energy s home performance bonus rebate is a great advantage for realizing savings for the program. The Air Source Heat Pump (ASHP) and Central AC measures are most cost effective when paired with additional measures. The combination of air sealing, duct sealing, duct distribution improvement and attic insulation to the highest level of R38 with or without solar window film are cost effective for all homes. The packages of measures result in annual MMBtu savings between 10% and 36%. The following measures, which are not currently eligible under Austin Energy s HPwES Program, were evaluated for cost effectiveness using the TRC test: CFL bulb installation and CFL fixture installation are cost effective as individual measures. However, due to the saturation of the area from the CFL coupon program this measure is not being considered for a direct rebate program. Low Flow water devices, aerators and showerhead measures, are cost effective in all four homes even without the consideration of water and sewer cost savings. Programmable thermostats modeled with a 5 hour setback period are cost effective in all four homes. On Demand DHW measures were not cost effective as individual measures. High efficiency DHW conventional units were not cost effective as individual measures. ENERGY STAR window replacement was not cost effective as an individual measure. 2 GDS Associates, Inc.

8 ENERGY STAR refrigerators and clothes washers were not cost effective as an individual measure at full cost Process Evaluation From interviews with program staff, a review of program documentation and from previous experience with HPwES Programs and other residential energy efficiency programs targeted toward existing buildings the following were identified as the best practices that should be continued as elements of the Austin Energy program and may serve as a model for others to replicate. Program Goals & Objectives: Both the 2007 NREL study and 2009 Sustained Excellence award support high achievements of Austin Energy in regards to the HPwES Program. Austin Energy has continually met all goals in terms of target participation numbers and has an extensive contractor network. Operation and Delivery: Austin Energy meets all of the HPwES Program operation requirements. A strong inspection group that is involved throughout the entire retrofit process, from the verification to the final inspection, is one of the key reasons for the success of the program. Austin Energy also meets national HPwES Program contractor guidelines and has a 20% value rule 1 to verify the quality of contractor work. Quality control. Having an Austin Energy inspector review each project and each contractor s performance is key to ensuring that: a) the program does no harm and b) cost effective improvements are made to the home. This often requires the education of homeowners in order for them to agree to make the recommended improvements. So while a quality review may investigate why certain cost effective measures were not implemented, it may reveal that the absence of the measure as a customer decision (for whatever reason) and not necessarily a shortcoming of the contactor. Home Performance with ENERGY STAR Certificate. Issuing an official document that certifies certain improvements have been made is a simple but very important best practice. It establishes, in writing from a credible source, that certain improvements have been made to the efficiency, health and comfort of the home. By having a certificate, a document that can stay with the property, it allows future owners, lenders, appraisers, realtors and all other stakeholders in the residential market to gain an understanding of the fact that the home has undergone specific energy improvements. Although it is not the silver bullet that transforms the residential market (appraisers still need to develop their own methodology via the Appraisal Institute to value these 1 A 20% value rule means that if a participating contractor fails 20% of their jobs within a six month period they will be pulled from the active list. 3 GDS Associates, Inc.

9 improvements), it, at a minimum, provides information to key market actors. This is something that more HPwES Programs should implement. Coordination and Communication: Internal program communications include a weekly newsletter that goes out to the Austin Energy staff announcing events, trainings and new program information, and monthly staff meetings. Participation: The number of customers that the program has served, even in a down economy is commendable. During the 2011 fiscal year, rebates reached 95% of Austin Energy s HPwES Program goal while the loans exceed the goal. Incentives: A variety of rebates and loan options are offered, including bonuses for completing all recommended conservation measures. Database and Tracking System: Data collected by the contractors to be entered in the Power Saver Program includes basic housing information such as square footage, the type of home, specific measures that qualify for rebates, account number, air test reports, and the rebate amounts. Continual Self Improvement. As intuitive as it may seem, not all programs have the ability to identify problems and proactively take measures to improve program implementation processes. This is something that GDS identified as a best practice of Austin Energy s HPwES. For example, an identified area that needed improvement was the need for electronic forms and ways of making the administration of the program less cumbersome. So often, program managers feel compelled to make a program better by instituting new policies, controls and requirements but with little or new actual improvement in the program overall. GDS commends Austin Energy in their efforts to streamline and simplify their processes. 1.2 Recommendations The following sections contain a summary of GDS recommendations based upon the evaluation of Austin Energy s HPwES Program Impact Evaluation The home performance bonus rebate should be expanded to include additional individual measures that can be combined to create more packages that are cost effective. The domestic hot water heater packages for all homes high efficiency storage, instant and heat pump water heaters are all cost effective when paired with attic insulation to the highest level of R38, air sealing and installation of programmable thermostats. The combination of air sealing, solar window film, programmable thermostat, ENERGY STAR refrigerator and clothes washer are cost effective for all four prototype homes. 4 GDS Associates, Inc.

10 The Central AC measures with SEER 14 and SEER 15 are cost effective when packaged with the following measures: o Attic insulation to R29, programmable thermostat o Attic insulation to R29, programmable thermostat, duct sealing and distribution improvement o Attic insulation to R29, programmable thermostat, duct sealing, distribution improvement and window solar film The Central AC measures with SEER 16 are cost effective for all three packages for the larger Home B and for Attic insulation to R29, programmable thermostat and window solar film for the smaller Home A. The ASHP measures with HSPF 8 / SEER 14 and HSPF 8 / SEER 15 are cost effective when packaged with the following measures: o Attic insulation to R29, programmable thermostat o Attic insulation to R29, programmable thermostat, duct sealing and distribution improvement o Attic insulation to R29, programmable thermostat, duct sealing, distribution improvement and window solar film The ASHP measures with HSPF 8.5 / SEER 16 and HSPF 9 / SEER17 are cost effective for all three packages for the larger Home B Process Evaluation GDS has identified the following as areas for improvement or lessons learned. Program Goals and Objectives: As a way of pushing the program to the next level, GDS recommends that Austin Energy set new goals in terms of program savings. GDS recommends that Austin Energy set a goal of obtaining a minimum of 20% energy savings for each participating home. Operation and Delivery: GDS recommends that Austin Energy require the following tests pre and post measure installation as part of the HPwES Program protocols: visual home inspection; blower door test to measure air leakage; duct blaster test to measure duct leakage; Manual J calculations for HVAC equipment sizing; and infrared test with an infrared camera to determine hot/cold spots and air movement through walls. Contractor Certification: GDS recommends that Austin Energy use the BPI certification and guidelines as well for its partner network. Contractor Training: Regular (e.g., monthly or quarterly) trainings are helpful in developing a superior home performance workforce. As part of the test in/test out procedures for the initial home assessment and final inspection, GDS has recommended several tests that are not currently part of the BPI requirements. GDS recommends that 5 GDS Associates, Inc.

11 Austin Energy offer monthly trainings to review program requirements, testing procedures, etc. that qualify for CEUs to the network of participating contractors, possibly in conjunction with existing or newly formed local or regional associations of home energy auditors and home performance contractors. GDS also recommends educating contractors so that there is a better understanding of HVAC commissioning; this has been identified as an area needing improvement in the program. The missing elements of this program (as well as many other existing home energy efficiency programs) is the proper training of home performance contractors to the correct sizing of HVAC equipment and distribution systems (ductwork). In new construction, which is the minimal energy codes and for ENERGY STAR Homes, right sizing has been a focus. However, in existing home programs, it is not often addressed and not often an area in which the implementation contractors are well versed. Requiring an element of training that focuses contractor s attention on the Air Conditioning Contractors of America s (ACCA) series of manuals that address right sizing will help develop a more educated and highly trained home performance workforce in the Austin area. Quality Assurance: Austin Energy should continue to require third party verification of installations and quality of work for 100% of HPwES Program projects. Austin Energy should require, as part of the final third party inspections, test outs for all tests conducted in initial home assessment. Post testing is important due to the inconsistent quality of installation and infrequent retro commissioning of equipment can increase space conditioning costs by 20% to 30%. Experts estimate that contractors install some 90% of HVAC equipment and insulation sub optimally, reducing efficiency by 20 30%. Austin Energy should continue to enforce the 20% value rule. This incents contractors to continue to perform quality work if they wish to continue as HPwES Program partners. Austin Energy staff should select 15 20% of all projects to receive a field quality insurance inspection. Projects should be selected on a random basis and at the request of the homeowner. Contractors should not inhibit or discourage homeowners from participating in the program quality assurance practices and such activity could result in disciplinary action. Coordination and Communication: GDS recommends that Austin Energy work on internal communications through the establishment of regular meetings and/or regular s to report program success, shortcomings, improvements, design changes, needs, etc. It is also important to consider who should be informed and what information should be disseminated on a regular basis. For example, employees fielding customer questions should be kept up to date on program design and implementation improvements while program management should be kept informed of program expenditures, participation levels, and savings. Additionally, GDS recommends that additional staff would enhance the program by providing more support to ensure the quality of the program. 6 GDS Associates, Inc.

12 Marketing and Customer Education: It is important to emphasize the non energy benefits of HPwES improvements when marketing and advertising the program, because some homeowners may not be aware that a whole house assessment can uncover performance issues in the home that directly affects the energy usage in the home. Participation and Barriers to Participation: Recommend working to mitigate the associated hassle of participation by migrating towards an integrated contractor approach and working towards reducing the burden of the application process. Recommend tailoring marketing efforts to focus on non energy benefits such as comfort, health, safety, and savings. Eligible Measures: GDS recommends Austin Energy review new technologies that have reached the level of commercial availability but need a stronger move into market transformation. For example, smart thermostats with IP and wireless capabilities are available and have the potential for savings. It is recommended that a review of these emerging technologies be initiated. Incentives: Rebates are favored over loans. Today s more educated homeowners understand the potential issues with accumulating additional debt and are therefore becoming more debt averse. Proper training of contractors and educating homeowners so that there is a better understanding of the fact that loans offered through a HPwES Program are low risk will help to encourage homeowners to use their own money rather than gravitating toward the so called free money or rebates only. Additionally, GDS recommends transitioning to a two path approach to incentives: (a) prescriptive and (b) performance based. The prescriptive approach would offer rebates a la carte for measures installed whereas the performance based approach would provide incentives proportional to the savings achieved. Database and Tracking System: Depending on the type of evaluation plan Austin Energy decides to proceed with for future iterations of the HPwES Program, GDS recommends Austin Energy standardize their database and tracking system for the program to ensure that all of the necessary data is collected and that it is reported consistently for all projects. Evaluation, Measurement & Verification: GDS recommends Option C of the IPMVP for the method to use to determine overall program kwh savings. Option C estimates savings for a whole facility and allows for assessing the interactive effects between various measures. The requirements for Option C include 24 months of continuous billing data (12 pre/12 post). 7 GDS Associates, Inc.

13 2 Program Overview Austin Energy has provided incentives, in the form of rebates and loans, to residential customers making energy efficiency improvements under the national HPwES Program. The efficiency improvements eligible under Austin Energy s HPwES Program include improvements to attic insulation, solar screens, window replacements, duct repair, duct sealing, and high efficiency heating and cooling systems. A variety of rebates and loan options are offered, including bonuses for completing all recommended conservation measures. 2.1 Goals and Objective One of the key goals of the national HPwES Program is to achieve a 20% overall savings for all the installed measures combined. The other metric of success is customer participation. The participation goals were developed by looking at the available funding (program budget) and at historical performance per unit (savings and cost) and then arriving at the number of participants (homes) based on that budget. 2.2 Rebate Program Measures Under the HPwES Rebate Program, customers may receive rebates for up to 20% of the cost of certain improvements, up to $1,575 per home. Rebates are offered for the following efficiency improvements. Table 2 1: Eligible Measures and Rebate Levels 2 Measure: Central AC or Heat Pump Package Unit AC or Heat Pump Attic Insulation to R 38 Solar Screens/Solar Film/ Low E Windows Radiant Barrier *Eligibility is determined on a case by case basis. Duct Replacement Duct Insulation External Combustion Air Attic Infiltration and Duct Sealing Duct System Performance Testing *Initial and final system performance tests and final blower door test required. Rebate Level Varies by efficiency levels; see tables below. Varies by efficiency levels; see tables below. Multiply the square footage of the home $ (per square foot) the R value added + $45 setup fee. $1.00 per square foot Multiply the square footage of accessible attic $0.10. $1.75 per linear foot. $1.25 per linear foot. $20.00 each. $0.12 per square foot. $200 per system. $50 per new return air improvement. 2 Home Performance with ENERGY STAR Rebate Amounts. th%20energy%20star/rebatelevels.htm 8 GDS Associates, Inc.

14 Table 2 2: Central AC or Heat Pump Rebate Levels Rebate Tier SEER EER Central Split Rebate Heat Pump Rebate $350 $ $450 $ & above 13.5 & above $550 $600 Table 2 3: New Package Unit Air Conditioner or Heat Pump Rebate Levels Rebate Tier SEER EER Central Split Rebate Heat Pump Rebate $400 $ & above 13.0 & above $500 $550 Participants may be eligible for Home Performance Bonus Rebates if a participant installs a new air conditioning unit or heat pump, sized to service at least 600 square feet per ton, and performs all of the following the weatherization measures as needed: Install additional attic insulation. Repair leaking AC ducts. Caulk plumbing and sinks. Weather strip doors. Install Low E windows, solar screens or awnings Install a radiant barrier. The rebate structure for the Home Performance Bonus programs is outlined below. Table 2 4: Home Performance Bonus Rebate Structure If Weatherization Rebate Total Is: Home Performance Bonus Is: $150 $250 $250 $250 $350 $400 $350 & above $ Program Statistics and Measures Implemented Austin Energy s HPwES Program serviced approximately 33,600 different projects. 3 The total number of loan projects is 7,924 and the total number of rebated projects is 25, A breakdown of the specific measures installed is provided in the following sections. 3 Project is defined as Bid_No in gdshpwes1.csv and includes both Rebate and Loan projects. 9 GDS Associates, Inc.

15 The following table contains the number of projects in which each measure was implemented. Table 2 5: Measure Installation Summaries 5 Measure: Specifications: No. Installations: Air Conditioner or Heat Pump HVAC 18,671 HVAC Bonus Rebate 4,469 HVAC Service 158 w/ Water Heater 4 External Combustion Air Furnace 529 w/ Water Heater 2,035 Duct Replacement 4,481 w/ Insulation 3,178 Additional Runs 695 Duct Insulation Unspecified 357 Drape or Bury 1,070 Air Infiltration & Duct Sealing Unspecified Air Infiltration 17,891 Air Infiltration <1600 9,261 Air Infiltration >1600 5,652 Air Infiltration > Duct System Performance Testing 2,010 Attic Insulation Unspecified 25,947 R0 R7 52 R8 R13 59 R14 R22 47 Solar Screens Unspecified 15,742 Eastern Shading 4,892 Northern Shading 15 Northeastern Shading 2,618 Northwestern Shading 3,209 Southeastern Solar Shading 2,989 Southern Solar Shading 5,654 Southwestern Solar Shading 4,447 Western Solar Shading 6,915 Window Films Skylight Covers 344 Low E Glass Window Replacement 276 Caulking and Weatherization Stripping Weatherization Bonus 9,993 Attic Radiant Barrier/Reflective Material Radiant Barrier 1,409 4 As tracked by Loan_Buydown and REBATE_AMT fields in file gdshpwes1.csv. 5 Defined as unique entries tracked in file: rebmrsr.csv 10 GDS Associates, Inc.

16 9,993 projects were eligible for the Home Performance Bonus Rebates; 4,469 projects were eligible for the HVAC Bonus Rebate. 6 The top ten measures tracked in the database as implemented in the HPwES Program include 7 : 1) Attic Insulation Unspecified 2) Air Conditioner or Heat Pump HVAC 3) Air Infiltration & Duct Sealing Unspecified 4) Solar Screens Unspecified 5) Weatherization Bonus Caulking and Weatherization Stripping 6) Air Infiltration <1,600 ft 2 7) Solar Shading Western 8) Solar Shading Southern 9) Air Infiltration >1,600 ft 2 10) Solar Shading Eastern The following table contains a summary of the HVAC equipment that was installed as part of the HPwES Program. Table 2 6: Installed HVAC Equipment Equipment Type Combined Unit AC Combined Unit HP No. Installations 20,809 3,145 Average Btu 32,400 3,800 Btu Range 23,000 70,000 9,000 62,500 Average Efficiency Rating 13.7% 13.3% Efficiency Rating Range 10.2% 20.0% 11.6% 18.0% Average SEER Rating SEER Rating Range Average EER Rating EER Rating Range File: rebmrsr.csv 7 These measures are ranked according to number of installation and not according to savings. 11 GDS Associates, Inc.

17 3 Evaluation Overview The following sections outline the methodology used by GDS to conduct an evaluation of Austin Energy s HPwES Program. 3.1 Impact Evaluation Overview GDS analyzed Austin Energy s HPwES data to identify savings in terms of avoided consumption and dollar savings (kw, kwh, $), program costs and cost effectiveness. GDS calculated the energy savings, program delivery costs, and cost effectiveness for the following: Each combination of weatherization measures offered; Total program costs to date; and Projected total program for entire two year period Energy Savings Model When selecting a model for energy savings, the EPA recommends basing the selection on the following criteria: 1) Objective. 2) Data requirements. 3) Simplest model that meets objective. Given the fact that Austin Energy was interested in understanding how individual measures performed when installed in an existing home in addition to gaining insight into how the measures interact to determine the cumulative effects on the total energy use of a home, GDS selected the Targeted Retrofit Energy Analysis (TREAT) model to identify energy and demand savings for the Home Performance measures and bundles of measures offered through the program. TREAT is a comprehensive energy analysis tool that can be used to: Create models quickly and easily with building component libraries; Calculate energy usage and predict energy savings; Calculate energy savings for individual improvements or assemble improvements in interactive packages; Calculate payback and savings to investment ratios (SIR); and Generate graphical reports. GDS used the TREAT model to identify energy and demand savings for the weatherization measures and bundles of measures offered through the HPwES Program. 12 GDS Associates, Inc.

18 It is important to realize that the impact analysis conducted for this evaluation is based on a typical Austin Energy customer home and common measures and packages of measures installed in Austin Energy s HPwES Program. The inputs to the TREAT model, described in detail in the following section, are based on primary and secondary research as well as engineering estimates and the knowledge of Austin Energy staff. While the model inputs were vetted, the models themselves were not calibrated to historical billing data. Thus the savings presented in this report should be viewed as an indicator of a measure s potential savings and not necessarily as actual savings as actual savings are dependent on a variety of variables, including those that cannot be model such as user behavior. For a more accurate estimate of actual program savings, GDS recommends Austin Energy conduct a billing analysis of their HPwES Program. More information on this type of evaluation is provided in Appendix B Baseline Homes Wherever possible, GDS used participant information tracked in the Austin Energy program database and information provided by Austin Energy program staff to establish the baseline energy use of homes prior to improvement. This information included: Home square footage, Existing insulation and weatherization levels, Existing infiltration, Existing window type, Thermostat set point, HVAC equipment specifications, Existing appliances, and Other data required by the TREAT model. GDS also relied on publically available data sources to model the typical home retrofitted in Austin Energy s HPwES Program; these included: U.S. Energy Information Administration (EIA) Residential Energy Survey (RECS) reports; and Home Performance with ENERGY STAR website and reports. After review of participants and program data, two baseline homes were modeled. These models were used to determine savings for various improvements with either electric heating and domestic hot water or natural gas heating and domestic hot water equipment. The homes were not reviewed for fuel switching. Two broad categories were determined: Home A was based on a smaller home built in the 1970s and Home B was based on a larger home built in the 13 GDS Associates, Inc.

19 1980s. These baseline homes assume mechanical equipment in the home is of the approximate vintage of the home. A summary of the model inputs, as well as average annual energy use for each home, is provided in the following table. Table 3 1: HPwES Model Home Assumptions TREAT Category Home A Home B Vintage 1970's 1980's Area 1245 sq ft 2400 sq ft Foundation Slab on Grade Attic Vented, Unconditioned Attic Wall Insulation 2x4 16 oc Fiberglass Batt (R12) Attic Insulation 2x8 16 oc Fiberglass Batt (R11) Slab Floor Insulation Uninsulated 4" Concrete Slab with Carpet (R2) Window Glazing Single Pane, Clear Double Pane, Clear Window Area ~ 13% of Wall Area Doors Two 36" Doors R2 Thermostat Non Programmable Lighting 50% CFL Bulb, 50% Incandescent Heating Set. Temp. 70 deg. F Cooling Set Temp. 77 deg. F Entering Cold Water Temp. 65 deg. F AC Output Capacity 36,000 Btu/hr AC SEER Duct Distribution Efficiency 85% Duct Insulation R Value R 2 R 5 Duct Leakage at 25PA / % conditioned sq ft 249 CFM / 20% 480 CFM / 20% 14 GDS Associates, Inc.

20 Table 3 2: HPwES Model Home Assumptions Natural Gas Equipment Heat and Hot Water Natural Gas TREAT Category Home A Home B Heating Natural Gas Furnace Forced air, Induced Draft Input Capacity 60,000 Btu/hr 80,000 Btu/hr Annual Efficiency 78% 80% Domestic Hot Water Natural Gas, Storage Water Heater Energy Factor 0.54 Annual Natural Gas Use therms/yr therms/yr Annual Electric Use 12,681.2 kwh/yr 15,502.2 kwh/yr Annual Energy Use MMBtu/yr MMBtu/yr Table 3 3: HPwES Model Home Assumptions Electric Equipment Heat and Hot Water Electric TREAT Category Home A Home B Heating Electric Air Source Heat Pump Input Capacity 36,000 Btu/hr 60,000 Btu/hr Annual Efficiency 6.3 HSPF 7 HSPF DHW Electric, Storage Water Heater Energy Factor 0.83 Annual Electric Use 18,027.7 kwh/yr 22,283.1 kwh/yr Annual Energy Use MMBtu/yr MMBtu/yr Appendix A includes TREAT reports providing information on the design heating and cooling load and base load for each of the four models. The design heating and cooling report presents results of the load sizing calculations. The base load report provides information on the base building energy consumption by appliances, domestic hot water and lightings Cost Effectiveness Models The selection of an appropriate benefit/cost test for energy efficiency programs requires consideration of existing state laws and regulations as well as the strengths and weaknesses of each benefit/cost test. According to the National Action Plan for Energy Efficiency report titled Understanding Cost Effectiveness of Energy Efficiency Programs, 8 the most common primary measurement of energy efficiency cost effectiveness is the Total Resource Cost (TRC) test. A 8 National Action Plan for Energy Efficiency, Understanding Cost Effectiveness of Energy Efficiency Programs, November GDS Associates, Inc.

21 positive TRC result indicates that the program will, over its lifetime, produce a net reduction in energy costs in the region where programs are being implemented. A standard methodology for energy efficiency program cost effectiveness analysis was published in California in 1983 by the California Public Utilities Commission and updated in December 1987, October 2001 and July It was based on experience with evaluating conservation and load management programs in the late 1970's and early 1980's. This methodology examines five perspectives: Total Resource Cost Test (TRC), Participant Test (PCT), Utility Cost Test (or Program Administrator Test) (PACT), Rate Impact Measure (RIM) Test, and Societal Cost Test (SCT). The table below summarizes the major components of these five benefit/cost tests. Examining this table is useful when trying to understand the differences among the five benefit/cost tests. Table 3 4: Components of Energy Efficiency Benefit/Cost Tests Component PCT PACT RIM TRC SCT Energy and capacity related avoided costs Benefit Benefit Benefit Benefit Additional resource savings Benefit Benefit Non materialized benefits Benefit Incremental equipment and installation costs 9 Cost Cost Cost Program overhead costs Cost Cost Cost Cost Incentive payments Benefit Cost Cost Bill savings Benefit Cost GDS has its own Benefit Cost Model which was used to compute the cost effectiveness of the various measures and measure packages eligible under Austin Energy s HPwES Program. The model was also used to compute the cost effectiveness of the overall HPwES Program as it was implemented to date. 10 The following inputs and the corresponding data sources were used to compute the benefitcost test ratios. 9 Total costs were used in this analysis as the installations were considered retrofit applications. Thus the baseline costs were assumed to be $0 making the incremental costs equal to the total costs. 10 A working copy of the model with the HPwES assumptions and inputs can be provided upon request. 16 GDS Associates, Inc.

22 Table 3 5: Benefit Cost Model Inputs and Data Sources Component Energy and capacity related avoided costs Additional resource savings Incremental equipment and installation costs Program overhead costs Incentive payments Bill savings Source Austin Energy Avoided Cost Data Engineering estimates Austin Energy Program data Engineering estimates Austin Energy Program expenditures Austin Energy Program data TREAT outputs Billing Analysis Austin Energy contracted GDS to assist in the evaluation of impacts associated with the HPwES Program. Per Austin Energy s request, GDS conducted a statistical billing analysis as one method for estimating program impacts. This section summarizes the analysis and findings of the study. The billing analysis provided a means for analyzing energy consumption for customers prior to and after enrollment in the HPwES Program. Using regression techniques, differences in energy consumption between the pre and post periods was quantified. The average difference measured between the two periods, controlling for factors other than the program, represents the estimated energy savings per home for all homes where customers have implemented one or more HPwES measures Model Specification Five alternative model specifications were tested, and while each provided similar results with respect to average energy savings per home, two are presented in this report. All models included monthly billing consumption for 560 individual customers and quantified a number of factors influencing household energy consumption, including number of days in the billing period, a time trend, heating degree days, and cooling degree days. Number of days in the billing period captures increases and decreases in monthly consumption due to varying days during a billing cycle. Number of days in the billing period was included in the billing history file provided by Austin Energy. The trend variable represents a time trend and takes the value of 1 through n for each premise and equates to the number of months corresponding to each premise in the modeling database. The trend variable accounts for increases in overall class consumption over time that was not captured by the other independent variables. The overall increase in consumption over time could be explained by different factors (increase in home size, increase in the number of end uses, declining real price of electricity, increases in number of people per household); however, these data series were 17 GDS Associates, Inc.

23 not available. Heating and cooling degree days capture the impacts of weather conditions over the course of the time periods modeled. A binary variable was included to identify the months during which a customer was enrolled in the HPwES Program (i.e., binary variable takes the value of 0 pre program and 1 post program implementation). The coefficient for this binary variable represents the average energy savings per home. The model determined to best capture the HPwES Program impacts was a panel model, which also included a series of binary variables, one for each customer, to differentiate differences in energy consumption across all customers due to factors that could not be included in the model due to data limitations (e.g., size of home, number of people in home, housing characteristics, electric end uses in home) 11. This model took the following form: Where: a,b,c, k Estimated coefficients m Billing month α Index representing the number of HPwES consumers CON Indicator variable for each control consumer α CDD Cooling degree days (base 65) in billing month HDD Heating degree days (base 65) in billing month DAYS Number of days in billing month PROGRAM Indicator for months when consumer was enrolled in the HPwES program ε Error term in billing month The model specification presented above was revised to replace the PROGRAM parameter, which represents the average monthly HPwES Program impact, with twelve individual program parameters, once for each month of the year. The model parameters and statistics for this alternative specification are provided in Section 4.5. This alternative model provides a means for estimating the differences in program impacts throughout the year. In theory, the greater program impacts would occur in the hottest months (July and August) and correspond to kwh savings from air conditioning. However, because the model was estimated using monthly billing cycle consumption rather than calendar month consumption, the greatest impacts 11 The homes in the data set were not limited to all electric homes however GDS did not have gas data and therefore did not include gas usage in the analysis. 18 GDS Associates, Inc.

24 correspond to those billing cycles represented in the model as August and September. 12 While the alternative model specification provides a means of estimating the potential variation in program impacts across months, it was concluded that the most reasonable estimate of program impacts across the year is one based on the single PROGRAM parameter as specified in the model presented above and in Section 4.5, Table The two models presented in this report represent panel models, which include billing data for each individual customer. The binary variables included in the model (CONS1 CONS560) represent intercepts for each customer; therefore, a single model intercept was not included, which is common in panel models. This was accomplished by including the NOINT option in the modeling process. An intercept term could have been included, and if so, binary variables for CONS2 CONS560 (the model intercept represents CONS1) would represent the differences between each customer to CONS1. The estimated coefficients for the trend, CDD, HDD, number of days, and program variables would be the same as the model estimated using the NOINT option. Data The data used to perform the analysis was provided by Austin Energy. Billing data was available for the period beginning October 2008 and ending February In order to develop a database with a relatively equal number of pre and post enrollment period observations 13, data from December 2009 through February 2012 was used to perform the modeling analysis. Data for a handful of customers was excluded due to excessively high consumption values or lack of observations in the pre and post periods Process Evaluation Overview The review of Austin Energy s HPwES Program was twofold. First, GDS developed a clear picture of how the current program worked through a review of program project documents and 12 As noted by one reviewer, it is unclear why the savings in October are comparable to August and July. GDS surmised that it could be that the billing periods lag actual consumption to the degree, for instance, that October consumption is influenced to a large degree by consumption during the last half of September. On the other hand, it could be that the model is over specified with respect to the number of program indicator variables. While they do show the potential variation in program impacts from a low impact month to a high impact month, use of the 12 month average impact in MODEL1 is more reasonable. 13 : GDS targeted 12 months of pre data and 12 months of post data how it varied by customer. Overall, there were approximately 7600 observations pre program and 7700 observations post program implementation premises were excluded. There was no specific cutoff for determining an outlier. Subjectively removed the 18 based on review of consumption patterns and identification of outliers. Extremely high positive or negative values. 19 GDS Associates, Inc.

25 interviews with Austin Energy HPwES Program staff. Information collected during these activities was used to document the program theory and design. In addition, in order to make recommendations for future program design and delivery, the process evaluation included a review of similar programs in the industry that may be considered best practices for this type of program. Results from all of these activities provide lessons learned from the projects completed to date, inform and support the impact evaluation to better understand how the savings were achieved, and identify what, if any, barriers exist as part of the program design. The process evaluation was designed to answer the following questions: How is the program working? What is working well and how could it be improved? What barriers are there to program participation? How well does the coordination work between Austin Energy and its partners? What are the effective marketing channels for reaching eligible customers? What are other effective program designs for HPwES based programs? What is most effective in providing energy efficiency improvements for these types of customers? Review of Program Materials To gain an understanding of the current Austin Energy HPwES Program operation, the evaluation team reviewed several program documents and reports that were available. These included: Austin Energy website, Austin Energy HPwES Program materials, Austin Energy HPwES Application, and National ENERGY STAR Home Performance website and materials. Our review of these documents was used to develop the researchable questions for the process evaluation, describe the current program operation and procedures, and generate discussion topics for program staff interviews Program Staff Interviews The program manager surveys are an essential component of the evaluation and establish a foundation for all evaluation activities. The surveys allow GDS to fully understand the HPwES Program as it is currently being offered by Austin Energy. We also discuss future plans for the program and how the process evaluation can best inform those proposed changes. This information provides the context necessary to develop and implement all other process, impact, and market evaluation efforts. GDS developed interview guides that were used to capture program related data from program managers and staff. These interviews helped us to assess the background, intended operations, and processes of the program s stated (and unstated) goals and objectives. The interviews also helped to identify the perceived barriers to program up take, previous experience with the 20 GDS Associates, Inc.

26 program, and modifications to any program components based on the previous program cycle as well as the rationale for those modifications. Questions regarding the following topics were discussed: a) Program Scope and Goals, b) Program Implementation, c) Data Tracking and Reporting, d) Program Progress, e) Program Marketing and Resources, f) Communications, and g) Conclusions Review of Relevant Programs and Best Practices In reviewing and comparing similar HPwES Programs and best practice reports, GDS researched several databases including DSIRE (Database of State Incentives for Renewables and Efficiency) as well as state specific websites. Additionally, websites such as the Department of Energy and ACEEE (American Council for an Energy Efficient Economy) were consulted for information regarding home performance programs throughout the country. A summary of the findings and conclusions from the review of these programs and best practice reports can be found in Section GDS Associates, Inc.

27 4 Impact Evaluation The following sections contain GDS s findings and recommendations from the impact evaluation of Austin Energy s HPwES Program. Working copies of all models used to develop savings and cost effectiveness estimates can be provided upon request. The findings and recommendations contained in these sections address the following tasks: Task 1: Analyze Austin Energy s HPwES Program data to identify peak power, energy and dollar savings (kw, kwh, $), program costs and cost effectiveness using appropriate cost tests. Task 2: Evaluate Austin Energy s HPwES Program prioritization strategy to determine highest program energy savings potential. Task 7: Provide recommendations for an Austin Energy residential conservation program that maximizes energy savings while minimizing the cost to the utility. 4.1 Energy Efficiency Improvements The following list of measures was evaluated for savings using TREAT for each baseline home. The annual fuel savings for each individual measure, annual cost savings for each home ($0.90 per therm, $0.113 per kwh), percent annual MMBtu reduction and Return on Investment (ROI) using customer cost after rebate are included in the tables following the list of measures. The improvement measures are incorporated into the existing baseline homes and are considered retrofit measures. For retrofit measures the total cost is used in the analysis because the savings are based on replacement of existing equipment. ROI = (Measure Life * Annual Savings + Rebate Measure Cost) / (Measure Cost Rebate) An ROI greater than 0.0 indicates that a customer will recoup all of the costs associated with the measure installation. However, there may be other benefits (e.g., comfort, safety, etc.) that cannot be quantified and represented in the ROI calculation, thus some judgment is also required to determine the true worth of a project. Also, when considering benefits and costs from a more global scale (i.e., looking at benefits to an electric system as opposed to a singular customer), cost effectiveness tests such as the TRC are more indicative of EE benefits and costs Infiltration Reduction Air infiltration reduction of the home was reduced from 0.75 ACH nat to 0.60 ACH nat for base Home A and from 0.60 ACH nat to 0.50 ACH nat for base Home B. 22 GDS Associates, Inc.