C

Consultant’s Report: Cost Effectiveness Study of Various Sustainable Building Standards in Response to NDAA 2012 Section 2830 Requirements

This appendix reproduces substantially (with minor reformatting) as submitted, a study prepared by Sarah Slaughter for the Committee to Evaluate Energy-Efficiency and Sustainability Standards Used by the Department of Defense for Military Construction and Repair, dated September 10, 2012. Note that in the reproduced report’s table of contents, the page numbers reflect the pagination that applies for inclusion in the current report, rather than the page numbers of the submitted report.



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C Consultant’s Report: Cost Effectiveness Study of Various Sustainable Building Standards in Response to NDAA 2012 Section 2830 Requirements This appendix reproduces substantially (with minor reformatting) as submitted, a study prepared by Sarah Slaughter for the Committee to Evaluate Energy-Efficiency and Sustainability Standards Used by the Department of Defense for Military Construction and Repair, dated September 10, 2012. Note that in the reproduced report’s table of contents, the page numbers reflect the pagination that applies for inclusion in the current report, rather than the page numbers of the submitted report. 91

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92 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD COST EFFECTIVENESS STUDY OF VARIOUS SUSTAINABLE BUILDING STANDARDS IN RESPONSE TO NDAA 2012 SECTION 2830 REQUIREMENTS PREPARED BY: Dr. Sarah Slaughter DATE: September 10, 2012 PURPOSE: National Research Council Committee to Evaluate Energy-Efficiency and Sustainability Standards Used by the Department of Defense for Military Construction and Repair

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APPENDIX C 93 TABLE OF CONTENTS OVERVIEW 95 Summary of Results, 96 Input for DOD Comprehensive Strategy, 97 SCOPE AND BACKGROUND 98 Department of Defense Policy on Sustainable Facilities, 98 Definition of Task, 99 METHODOLOGY FOR ECONOMIC EVALUATION OF SPECIFIED RATING SYSTEMS 100 AND STANDARDS AND DEVELOPMENT OF ANALYTICAL TOOLS Economic Efficiency Analysis, 101 Study Methodology for Economic Efficiency Analysis, 104 Sensitivity Analysis on Study Period, 105 Sensitivity Analysis on Discount Rate, 105 Sensitivity Analysis on Factor Price Escalation, 106 Study Methodology Using Prototype Buildings and Climate Zones, 108 Study Methodology for Benefit and Cost Categories, 110 Study Methodology for Data Collection for Prototype Buildings, 111 Study Methodology for Data Collection for Standards and Ratings Systems, 112 ASHRAE Standards Data: Building Models, 113 LEED Data: Certified Buildings from US Green Building Council (USGBC), 114 Green Globes Data: Certified Buildings from Green Building Initiative (GBI), 116 RESULTS OF ECONOMIC EFFICIENCY EVALUATION OF SPECIFIED BUILDING 118 STANDARDS AND RATING SYSTEMS ASHRAE 90.1-2010—Economic Efficiency Results Across Building Types and Locations, 119 Long-Term Cost-Benefit, 119 Rate of Return on Investment, 122 Payback, 123 Summary Results for ASHRAE 90.1-2010, 124 ASHRAE 189.1-2011—Economic Efficiency Results Across Building Types and Locations, 125 Long-Term Cost-Benefit, 126 Rate of Return on Investment, 129 Payback, 129 Summary Results for ASHRAE 189.1-2011, 131 LEED—Economic Efficiency Results Across Building Types and Locations, 131 Long-Term Cost-Benefit, 133 Rate of Return on Investment, 137 Payback, 138 Summary Results for LEED, 138 Green Globes—Economic Efficiency Results Across Building Types and Locations, 140 Long-Term Cost-Benefit, 142 Rate of Return on Investment, 144 Payback, 145 Summary Results for Green Globes, 146 Summary of Results of Economic Efficiency Evaluation, 147 2

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94 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD APPLICABILITY OF COST EFFECTIVENESS STUDY TO DOD MILITARY 150 CONSTRUCTION AND RENOVATION Implications of Economic Efficiency Evaluation for Military Construction and Renovation Investments, 150 Applicability of Analytical Framework for DOD Military Construction, 152 Timing of Economic Efficiency Analysis for Decision Support, 154 Current DOD Data Collection for Strategic Investment in DOD Capital Facility Assets, 154 Industry and Market Factors for Long-term Cost Efficiency of Military Construction and Renovation, 156 APPENDIX A: SENSITIVITY ANALYSIS DATA 158 APPENDIX B: PROTOTYPE BUILDINGS—CHARACTERISTICS 159 APPENDIX C: DEFINITIONS OF BENEFIT—COST CATEGORIES 162 APPENDIX D: BASELINE PROTOTYPE BUILDINGS RESOURCE USAGE AND FACTOR 163 UNIT PRICES BY LOCATION APPENDIX E: FEDERAL STATUTES FOR LIFE CYCLE COST ANALYSIS 164 APPENDIX F: REFERENCES FOR FEDERAL REPORTING REQUIREMENTS FOR 165 BENEFIT-COST CATEGORIES APPENDIX G: ASHRAE DATA GENERATION METHODOLOGY 165

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APPENDIX C 95 OVERVIEW In the NDAA 2012 Section 2830(a), Congress required the Department of Defense to submit a report that includes a cost-benefit analysis, return on investment, and long-term payback for specific building standards and rating systems (ASHRAE 189.1 and 90.1, LEED Silver, Gold, and Platinum, and other ANSI accredited standards such as Green Globes). It also required the DOD to provide a policy prescribing a comprehensive strategy for the cost-effective pursuit of design and building standards that include specific energy-efficient standards and sustainable design attributes based on those findings. At the request of the Office of the Secretary of Defense for Installations and Environment, the National Research Council (NRC) appointed an ad hoc committee to review the literature on the state-of-the-knowledge about the economic efficiency of sustainable buildings, to evaluate a consultant-generated methodology and analysis of the economic efficiency of the specified building design standards, and to identify potential factors and approaches that the DOD should consider in developing a comprehensive strategy for its entire portfolio of facilities that includes standards for energy-efficiency and sustainable design. This report outlines the methodology and findings by the consultant to analyze the cost- benefit, return on investment, and long-term payback for the specified building design standards and ratings systems. The second part of the study tested the applicability of the analytical tools to DOD facilities going forward, as input to the DOD comprehensive strategy. The consultant developed and applied the methodology for this study building on existing research, methods, best practices, and tools to analyze the economic efficiency of the specified building standards and rating systems and to provide input into the development of the DOD comprehensive strategy. The methodology was developed to address robustness, validity, and replicability of the analysis of the specific building design standards and rating systems, and to ensure applicability to DOD facilities. The methodology (described in the Methodology section of this report) consists of the following elements: 1. Economic Efficiency Analysis: This study follows standard economic analysis methodologies and data collection approaches to calculate long-term cost-benefits (Present Value Net Savings), return on investment, and payback, as required in the NDAA 2012 Section 2830. The study developed an analytical approach to assess the long-term cost-benefits of alternatives for a range of scenarios that represent uncertain future conditions. This approach was applied using a set of tools developed specifically for this study to provide sensitivity analyses of the results under different scenarios, specifically for variations in the discount rate, time period, and price escalation rates for energy and water costs. This study also utilized the NIST Building Life-Cycle Cost (BLCC) software to calculate present value net savings, (adjusted) rate of return on investment, and payback. 2. Prototype Buildings and Locations: This study established a common basis on which to calculate the long-term cost-benefits, return on investment, and payback using prototype buildings and selected locations to represent the heating and cooling loads and local factor prices that influence the economic efficiency calculations. Specifically, this study utilized the results and characteristics of two building prototype models from the Department of Energy (DOE) Pacific Northwest National Laboratory (PNNL) study that are most applicable to DOD facilities, specifically the “medium office” and “small hotel” models (corresponding to administrative buildings and barracks, respectively). This study also utilized a subset of five locations from the DOE PNNL set of 15 locations that reflect the diversity of geographic regions across the continental US to create the baseline prototype buildings. 4

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96 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD 3. Benefit and Cost Categories: This study includes existing reporting categories for DOD under the Annual Energy Management Report to Congress and other reports for the analysis of costs and benefits for high performance buildings. The benefit-cost categories are: Investment (initial investment and major repair/replacement costs); Operations, Maintenance, and Repair (OM&R) costs, including: Energy use (building and supporting/site facilities); Water use (building and supporting/site facilities); Solid waste (municipal and hazardous); and Building/site O&M (general, cleaning, and landscaping). The strategy for data collection addressed the issues of validity and accuracy of the results. In discussions with staff from ASHRAE, Green Building Initiative, and the US Green Building Council, the cost and benefit data for the analysis of the specified building rating systems (Green Globes and LEED) was developed using data from actual certified commercial/private projects that are similar to (and brought into conformance with) the characteristics of the selected prototype buildings (i.e., medium office and small hotel) and selected locations. The ASHRAE standards data were generated using the PNNL building models for the two prototype buildings in the selected locations. Separately, and in parallel with the analysis of the specified standards and rating systems, the consultant worked with DOD installation, HQ, construction agent and OSD teams to test the applicability of the analytical approach, process, and tools to DOD military construction and renovation. SUMMARY OF RESULTS In direct response to the NDAA 2012 Section 2830, to provide a cost-benefit analysis, return on investment and long-term payback for the specified design standards, this study analyzed the (Present Value) Net Savings, (Adjusted) Rate of Return on Investment, and Payback in accordance with the Office of Management and Budget (OMB) Circular A-94 Revised (1992). These potential Net Savings can also be viewed as the potential future additional costs that may be incurred for these building types and locations under these scenarios. The Results section of this report provides the Net Savings for the Long-Term Cost-Benefit with the sensitivity analysis, as well as the Rate of Return on Investment and Payback, for each specified standard and rating systems using the two building types (i.e., residential and office) and five locations that represent the variety of climate conditions and markets across the continental U.S. Specifically, this study analyzed the economic efficiency of buildings built under the guidance of: ASHRAE Standards 90.1-2010 and 189.1-2011; LEED Silver, Gold and Platinum Certifications; and Green Globes One, Two, Three and Four Certifications. The results of the analysis in this study indicate that the building standards and rating systems provide buildings that are economically efficient depending on building type and location. Specifically, the Long-term Cost-Benefit analysis of ASHRAE Standard 90.1-2010 provided significant Net Savings in energy reductions for both building types and in all 5 locations. ASHRAE Standard 189.1-2011 provided greater Net Savings than 90.1-2010 across all locations for both building types in both energy and water cost reductions. In particular, the water cost reductions equaled approximately 50% of the Annual Savings across the building types and locations. ASHRAE 189.1-2011 also includes the requirement for on-site energy generation, and these incremental initial construction costs were included, and the on-site energy was used to offset the building energy used, so the overall building energy reductions were greater for 189.1-2011 than for 90.1- 2010. Buildings built under the guidance of the LEED rating system (Silver, Gold and Platinum Certification levels) and the Green Globes rating system (One, Two, Three and Four Globes certification levels) are economically efficient depending on building type and location, and are 5

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APPENDIX C 97 highly sensitive to the incremental initial construction cost. The LEED Volume Certification program could further increase cost-effectiveness through pre-approval of standardized designs and management procedures, and coordinated procurement programs. In addition, the recent DOD guidance (2010) specifying that 40% of all points in those rating systems must be in energy and water categories will increase the economic efficiency (as measured in this study) of DOD buildings using these rating systems. It must be noted, however, that these results are highly dependent on the data provided for these data samples, particularly the reported initial construction costs. The sensitivity analysis incorporated variations in energy and water price escalations, as well as the cost of capital (represented by the discount rate). The results indicate that Net Savings for the specified buildings standards and rating systems would increase significantly with annual price escalations of 2% for energy and 4% for water and wastewater, which has been experienced in some locations of the US. The building standards and rating systems could reduce the vulnerability of DOD installations to price shocks—and increase cost-effectiveness—by reducing the use of these resources. The sensitivity analysis results also indicate that, even if the prices for energy and water decrease and the cost of capital increases (represented by a discount rate of 3%), most facilities built under the guidance of the standards and rating systems remain economically efficient. INPUT FOR DOD COMPREHENSIVE STRATEGY This study recognizes that the core purpose of military construction and renovation is to provide high performance facilities that are effective and efficient. Specifically, the results of this study and the application of the analytical approach can be used to identify opportunities to improve effectiveness and efficiency, such as to reduce the resource usage (and the related burden on neighboring communities), reduce vulnerabilities to price increases, and increase overall resiliency by reducing the “baseload” resource requirements under normal and extreme conditions. The primary objective of this study is to ensure the usefulness of the analytical approach and results to aid decision-making for strategic investments in DOD capital facility assets. The results of the economic evaluation of the building standards and rating systems presented in this report have direct applicability to the development of the DOD comprehensive strategy for cost-effective military construction and renovation. This study highlighted opportunities for cost-effective high performance buildings built under the guidance of the specified standards and rating systems for different building types, specifically for a residential facility and an office building, in both energy and water usage. It also examined the potential economic value in different locations that represent the variety of climate zones and urban/rural markets across the U.S., incorporating local factor unit prices and conditions that affect cost- efficiency. The sensitivity analysis provides insight into the variability of cost-effectiveness, in particular, potential escalation of energy and water prices and changes in the cost of money (as represented by the discount rate). The implication of the results of the economic evaluation of the specified building standard and rating systems for the DOD comprehensive strategy for cost-effective military construction is that ASHRAE 189.1-2011 (which includes ASHRAE 90.1-2010 by reference) would likely provide economically efficient high performance military facilities. The voluntary ratings systems of LEED and Green Globes can provide important guidance for overall high performance facilities (including attributes not measured in this study) as well as third party verification, and buildings certified under these rating systems would be cost-efficient if the incremental initial investment costs are within a margin (in these samples, if the incremental initial investment cost is less than 20% of the baseline investment cost) and the annual savings are sufficient to offset that incremental cost. 6

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98 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD It must be noted, however, that those results are highly sensitive to the heating and cooling loads for different climate zones and to the local factor unit prices. Consideration of specific choices associated with the application of those standards for design development and implementation should be evaluated grounded in the specific local context. The second portion of this study tested the applicability of the analytical approach, process and tools developed for this research to military construction and renovation projects going forward, as further input for the DOD comprehensive strategy. The results from example applications of the analytical approach using empirical data from actual DOD buildings were reviewed with staff from the selected installations, HQ, construction agents, and the Office of the Secretary of Defense. The exercise provided important feedback for the potential application of the economic efficiency evaluation process for DOD military and construction going forward. In particular, the discussion raised certain challenges and opportunities associated with economic efficiency evaluations. First, the analytical approach of economic efficiency analysis would be most effectively applied across a portfolio of projects—with respect to the overall installation requirements—that increase mission effectiveness and economic efficiency. Second, the application of an economic efficiency analysis requires access to credible and verifiable data on the initial investment costs, major repair/replacement costs, and operations, maintenance and repair costs over the expected life of the facility. The DOD components, installations and construction agents are initiating specific programs to collect information on energy and sustainability performance for capital facility assets, including both the expected and actual performance of the facilities. The effective use of an economic efficiency analysis approach may require additional data collection to aid decision-making. Finally, further research is needed to determine the extent to which industry development as a whole may increase the cost-effectiveness of military construction and repair. The Department of Defense has incorporated life cycle cost analysis into all military construction and renovation projects, and the DOD components have launched several initiatives to incorporate economic assessment into decision making for military construction and renovation. This study provides the results of the economic evaluation of the specified building standards and rating systems, and the applicability of the analytical approach, as input into the development of the DOD comprehensive strategy going forward. SCOPE AND BACKGROUND DEPARTMENT OF DEFENSE POLICY ON SUSTAINABLE FACILITIES Recognizing the significant role of buildings in solving national issues such as energy independence and security, and the opportunity for federal leadership, Congress and two Presidential administrations have enacted laws and issued Executive Orders directing federal agencies to develop high-performance, energy efficient, and sustainable federal buildings. To implement these mandates, federal departments and agencies have issued policies for sustainable building design. The Department of Defense (DOD) and its components manage more than 500,000 buildings and structures worldwide, containing more than 2.1 billion total square feet of space. The annual energy budget for these facilities is more than $4 billion. The DOD’s Sustainable Building Policy includes supplementary information (October 2010) that specifies that: 1. All new building design and construction shall conform to the Guiding Principles in the High Performance and Sustainable Buildings Memorandum of Understanding. 7

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APPENDIX C 99 2. DOD components will design, build, and certify as appropriate, all new construction projects, at a minimum, to the Silver level of the Leadership in Energy and Environmental Design (LEED) green building rating system (or equal). Beginning in FY12 for projects in the planning stage, the sum of energy and water efficiency credits shall equal or exceed 40 percent of the points required for a LEED Silver (or equal) rating; this highlights the importance of pursuing additional energy- and water-related credits in areas such as cool roofs and day lighting. 3. All repair/renovation projects in existing buildings shall also conform to the Guiding Principles where they apply. The DOD components will design, execute and certify major repair/renovation projects to be LEED Silver, at a minimum, where appropriate. 4. Reducing total cost of ownership is intrinsic to sustainable buildings. The DOD components shall incorporate life cycle and cost/benefit analysis into design decisions for new construction and renovation/repair projects. 1 Concerns have been raised in Congress that DOD buildings conforming to this policy may not be cost effective or achieving federal mandates for energy efficiency. In response to these concerns, the National Defense Authorization Act (NDAA) for Fiscal Year 2012, Section 2830, requires the Department of Defense (DOD) to submit a report to the congressional defense committees on energy efficiency and sustainability standards used by the DOD for military construction and repair. The report must include a cost-benefit analysis, return on investment, and long-term payback for the following building design standards: American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) Standard 189.1-2011 for the Design of High-Performance, Green Buildings Except Low- • Rise Residential Buildings ASHRAE Energy Standard 90.1-2010 for Buildings Except Low-Rise Residential Leadership in Energy and Environmental Design (LEED) Silver, Gold, Platinum, and • Volume Certifications • Other American National Standards Institute (ANSI) accredited standards, such as Green Globes. • The report must also include a copy of the DOD policy prescribing a comprehensive strategy for the pursuit of design and building standards that include specific energy-efficient standards and sustainable design attributes based on the cost-benefit analysis, return on investment, and demonstrated payback for the aforementioned building design standards. DEFINITION OF TASK At the request of the Office of the Secretary of Defense for Installations and Environment, an ad hoc committee was appointed by the National Research Council (NRC) to: (1) evaluate the completeness, accuracy, and relevance of a literature review that synthesizes the state-of-the- knowledge about the costs and benefits, return on investment, and long-term payback of specified design standards related to sustainable buildings; (2) evaluate a consultant-generated methodology and analysis of the cost-benefit, return on investment, and long-term payback for the specified building standards and rating systems in NDAA 2012 Section 2830, and the test for the potential applicability of the analytical approach to military construction and renovation using empirical data 1Dorothy Robyn (2010). “Department of Defense Sustainable Buildings Policy.” Office of the Secretary of Defense, Deputy Under Secretary of Defense (Installations & Environment). 8

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100 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD from DOD buildings; and (3) identify potential factors and approaches that the DOD should consider in developing a comprehensive strategy for its entire portfolio of facilities that includes standards for energy-efficiency and sustainable design. The consultant, working with the Office of the Secretary of Defense and the military components, and in conjunction with representatives of the organizations for the specified standards and rating systems organizations, developed a methodology for: 1) analyzing the cost- benefit, return on investment, and long-term payback achievable using sustainable building standards specified in the NDAA 2012 Section 2830 using an example building; and 2) gathering and analyzing empirical data from DOD buildings to evaluate the cost benefit, return on investment, and long-term payback achievable using sustainable building standards specified in the NDAA 2012 Section 2830. The consultant then gathered and analyzed example building data to calculate the cost- benefit, return on investment, and long-term payback achievable using sustainable building standards specified in the NDAA 2012 Section 2830. The methodology for this study is described in the following section, followed by the results of the analysis for the specified building standards and rating systems. The consultant also worked with the DOD installation, HQ, and construction agent teams to gather and analyze empirical data from selected DOD buildings to demonstrate the methodology to determine the cost-benefit, return on investment, and long-term payback achievable using the referenced sustainability standards. The final chapter provides potential factors and approaches that the DOD should consider in developing a comprehensive strategy for military construction and renovation that includes standards for energy efficiency and sustainable design. METHODOLOGY FOR ECONOMIC EVALUATION OF SPECIFIED RATING SYSTEMS AND STANDARDS AND DEVELOPMENT OF ANALYTICAL TOOLS The consultant developed and applied the methodology building on existing research, methods, best practices, and existing tools to analyze the economic efficiency of the specified building standards and rating systems and to provide input into the development of the DOD comprehensive strategy. The methodology was developed to address robustness, validity, and replicability of the analysis of the specific building design standards and rating systems, and to ensure applicability to DOD facilities. The methodology consists of the following elements: 1) Economic Efficiency Analysis: This study follows standard economic analysis methodologies and data collection approaches to calculate long-term cost-benefits (Present Value Net Savings), return on investment, and payback, as required in the NDAA 2012 Section 2830. The study developed an analytical approach to assess the long-term cost-benefits of alternatives for a range of scenarios that represent uncertain future conditions. This approach was applied using a set of tools developed specifically for this study to provide sensitivity analyses of the results under different scenarios, specifically for variations in the discount rate, time period, and price escalation rates for energy and water costs. This study also utilized the NIST Building Life-Cycle Cost (BLCC) software to calculate present value net savings, (adjusted) rate of return on investment, and payback. 2) Prototype Buildings and Locations: This study established a common basis on which to calculate the long-term cost-benefits, return on investment, and payback using prototype buildings and selected locations to represent the heating and cooling loads and local factor prices that influence the economic efficiency calculations. Specifically, 9

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APPENDIX C 101 this study utilized the results and characteristics of two building prototype models from the Department of Energy (DOE) Pacific Northwest National Laboratory (PNNL) study that are most applicable to DOD facilities, specifically the “medium office” and “small hotel” models (i.e., corresponding to administrative buildings and barracks, respectively). This study also utilized a subset of five locations from the DOE PNNL set of 15 locations that reflect the diversity of geographic regions across the continental US to create the baseline prototype buildings. 3) Benefit and Cost Categories: This study includes existing reporting categories for DOD under the Annual Energy Management Report to Congress and other reports for the analysis of costs and benefits for high performance buildings. The benefit-cost categories are: a. Investment (initial investment and major repair/replacement costs; b. Operations, Maintenance, and Repair (OM&R) costs, including: i. Energy use (facility and supporting/site facilities); ii. Water use (facility and supporting/site facilities); iii. Solid waste (municipal and hazardous); and iv. Building/site O&M (general, cleaning, and landscaping). The strategy for data collection addressed the issues of validity and accuracy of the results. In discussions with staff from ASHRAE, the Green Building Initiative, and the US Green Building Council, the data for the analysis of the specified building rating systems (Green Globes and LEED) were provided based on actual certified commercial/private projects that are similar to (and brought into conformance with) the characteristics of the selected prototype buildings (i.e., medium office and small hotel) and locations. In discussions with the staff from ASHRAE, the data for the analysis of the specific building standards were generated using the PNNL building models for the two prototype buildings in the selected locations. ECONOMIC EFFICIENCY ANALYSIS This study analyzed the economic efficiency of the specified building standards and rating systems in accordance with the Office of Management and Budget (OMB) Circular A-94 Revised (1992), which provides “general guidance for conducting benefit-cost and cost-effectiveness analyses.” (Appendix E refers to legislative requirements for life cycle cost analysis.) OMB Circular A-94 provides the following definitions: Benefit-Cost Analysis—A systematic quantitative method of assessing the desirability of government projects or policies when it is important to take a long view of future effects • and a broad view of possible side-effects. Cost-Effectiveness—A systematic quantitative method for comparing the costs of alternative means of achieving the same stream of benefits or a given objective. 2 • National Institute of Standards and Technology (NIST) Life-Cycle Costing Manual for the Federal Energy Management Program (1996) defines life cycle cost analysis (LCCA) as An economic method of project evaluation in which all costs arising from owning, operating, maintaining, and ultimately disposing of a project are considered to be potentially important in that decision. LCCA is particularly suitable for the evaluation of building design 2 Office of Management and Budget (1992). Circular A-94 Appendix A, Definitions of Terms, Revised. 10

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APPENDIX C 167 standard relative to a baseline standard(s). Evaluation of the final standard is a very time consuming process and consequently follows publication of the standard by a significant time lag. This is the current situation for both Standards 90.1-2010 and 189.1-2011. The first costs and final energy savings will be formally documented but the analysis and results are not currently available for use in this project. Recognizing that the final reports for Standards 90.1-2010 and 189.1-2011 were not available, the challenge was to estimate the first costs using information contained in currently published reports. These first costs are understood to be approximate. This report presents the methodology used to develop the first costs and the final results. It is critical to understand that the calculation of the first costs is based on the energy savings. Thus, this report contains the annual energy savings as well as the first costs. 2.0 Objective The objective of this analysis was to determine the first costs for ASHRAE Standards 90.1- 2010 and 189.1-2011 relative to the baseline ASHRAE Standard 90.1-2004. 3.0 Background The first costs for ASHRAE Standards 90.1-2010 and 189.1-2011 had not been previously calculated and reported so they have to be derived from the data that was readily available. The Technical Support Documents developed in support of the ASHRAE Advanced Energy Design Guides from PNNL for the medium office building (Thornton, 2009) and highway lodging (Jiang) provided the only first cost data for each city. However, neither of these reports contained all of the individual energy results which were needed in order to determine the first costs. Mike Rosenberg, from PNNL, was contacted and provided the EnergyPlus simulation results which contained the required energy information. 4.0 Representative Cities All of the analysis was intended to use the same representative five cities, see Table 1. However, in some of the reports Memphis was replaced with Atlanta. Figure 1 is an overlay of the representative cities in their climate zones. Each climate zone is shown as a separate color. The representative cities are shown as a white square while Atlanta is a blue square. In general the representative cities are centrally located within the climate zones. The climatic conditions for Atlanta are very close to Memphis so applying the data for Atlanta to Memphis was assumed to be appropriate. Table 1 Representative Cities CZ City HDD65 CDD50 1 Miami 200 9474 2 Phoenix 1350 8425 3 Memphis 3082 5467 3 Atlanta 2991 5038 4 Baltimore 4704 3709 6 Helena 8031 1922 76

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168 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD Figure 1 Overlay of Representative Cities by Climate Zones 5.0 Supporting Documents Multiple reports have been previously completed which contain energy saving results in some form, either for individual cities and building types or weighted averages by climate zone or a national average, see Table 2. The information in these reports was used to estimate the first costs and annual energy savings for Standards 90.1-2010 and 189.1-2011. Table 2 Sources of Information Report Subject 90.1 Base Standard Energy Savings PNNL-17875 Highway Lodging— 1999 39.3% (Jiang) 30% AEDG 2004 33.5% PNNL-19004 Medium Office— 2004-VAV System 46.3% (Thornton 2009) 50% AEDG 2004-Radiant System 56.1% PNNL-20405 Std. 90.1-2010 2004 25.6% PPL (Thornton 2011) 32.7% w/o PPL PNNL-189.1 Comparison between Medium Office 3.9% Progress Indicator (Liu) 189.1-2009 and 90.1-2010 Small Hotel 17.4% NREL/TP-550-47906 Std. 189.1-2009 2007-Medium Office 31.0% (Long) 2007-Small Hotel 34.3% 6.0 Technical Approach Fundamentally, the technical approach was to use the ASHRAE Advanced Energy Design Guides energy savings for each specific building and location which also had the incremental first costs. This information was used to determine a linear relationship between the incremental first costs in $/ft2 and the energy savings as a percent. This linear relationship was derived for each 77

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APPENDIX C 169 building type in each city. The $/ft2 was assumed to go through the origin when there were no energy savings. As an example of this concept, Figure 2 shows the five locations for both building types. A straight line through the origin is shown that connects the average for each building type. However, the actual calculations use a specific linear relationship for each individual city and building type which is the slope of each line. The first step in this process was to estimate the energy savings for both of the building types in all five cities relative to the baseline Standard 90.1-2004. Those results were then used to approximate the first costs for Standards 90.1-2010 and 189.1-2011. This process was straight forward for Standard 90.1-2010. However, for Standard 189.1-2011 it was more complicated because photovoltaic (PV) panels were used to meet the annual on-site renewable energy requirements so those first costs had to be analyzed separately. Furthermore, the results for Standard 189.1-2009 could not be used directly because the requirements for the annual on-site renewable energy changed between Standards 189.1-2009 and 189.1-2011 which impacts the first costs so additional analyses were required. Figure 2 Incremental First Costs vs Energy Savings 7.0 Incremental First Costs The data in Tables 3 and 4 formed the basis for all of the first cost calculations used in this study. These incremental first costs account for all of the upgrades due to more stringent criteria for the envelope, lighting, HVAC and SWH. These incremental costs do not account for any of the first costs for the PV systems so they need to be calculated separately. 78

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170 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD Table 3 Incremental First Costs for the Medium Office Medium Office (PNNL 19004) building type in each city. The $/ft2 was assumed to go through the origin when there were no energy savings. As an example of this concept, Figure 2 shows the five locations for both building types. A straight line through the origin is shown that connects the average for each building type. However, the actual calculations use a specific linear relationship for each individual city and building type which is the slope of each line. The first step in this process was to estimate the energy savings for both of the building types in all five cities relative to the baseline Standard 90.1-2004. Those results were then used to approximate the first costs for Standards 90.1-2010 and 189.1-2011. This process was straight forward for Standard 90.1-2010. However, for Standard 189.1-2011 it was more complicated because photovoltaic (PV) panels were used to meet the annual on-site renewable energy requirements so those first costs had to be analyzed separately. Furthermore, the results for Standard 189.1-2009 could not be used directly because the requirements for the annual on-site renewable energy changed between Standards 189.1-2009 and 189.1-2011 which impacts the first costs so additional analyses were required. Figure 2 Incremental First Costs vs Energy Savings 7.0 Incremental First Costs The data in Tables 3 and 4 formed the basis for all of the first cost calculations used in this study. These incremental first costs account for all of the upgrades due to more stringent criteria for the envelope, lighting, HVAC and SWH. These incremental costs do not account for any of the first costs for the PV systems so they need to be calculated separately. 78 Energy Savings Incremental FC Incremental FC Slope CZ City (%) ($) ($/ft2) ($/ft2/%) 1 Miami 47 175,176 3.27 0.0695 2 Phoenix 53 206,606 3.85 0.0727 3 Atlanta 42 211,909 3.95 0.0941 4 Baltimore 43 196,787 3.67 0.0854 6 Helena 45 127,134 2.37 0.0527 Table 4 Incremental First Costs for the Small Hotel Small Hotel (PNNL 17875) Energy Savings Incremental FC Incremental FC Slope CZ City (%) ($) ($/ft2) ($/ft2/%) 1 Miami 27 129,607 3.00 0.1111 2 Phoenix 29 138,752 3.21 0.1107 3 Memphis 32 127,498 2.95 0.0922 4 Baltimore 34 120,879 2.80 0.0824 6 Helena 32 114,183 2.64 0.0825 8.0 First Costs—Standard 90.1-2010 The initial step in determining the first costs is to calculate the percentage of energy savings between the baseline Standard 90.1-2004 and 90.1-2010. In order to perform this calculation the electrical and gas energies are added together using kWh as the common metric which is listed as Energy in Tables 5 and 6. Table 5 Standard 90.1-2010 Medium Office First Costs 90.1- 90.1- 90.1- 90.1- 2004 2010 Incremental 2004 2010 Energy Energy Save FC FC Baseline Total CZ City (kWh) (kWh) (%) ($/ft2) ($) ($) ($) 1 Miami 802,795 609,372 24.09 1.68 89,801 6,052,000 6,141,801 2 Phoenix 805,658 604,243 25.00 1.82 97,456 5,970,500 6,067,956 3 Memphis 788,061 566,718 28.09 2.64 141,712 5,754,000 5,895,711 4 Baltimore 823,329 579,172 29.65 2.53 135.714 6,273,000 6,408,714 6 Helena 856,362 621,534 27.42 1.45 77,472 5,944,500 6,021,972 79

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APPENDIX C 171 Table 6 Standard 90.1-2010 Small Hotel First Costs 90.1- 90.1- 2004 2010 Incremental 90.1-2004 90.1-2010 Energy Energy Save FC FC CZ City (kWh) (kWh) (%) ($/ft2) ($) Baseline ($) Total ($) 1 Miami 905,411 803,172 11.29 1.25 54,204 5,049,888 5,104,092 2 Phoenix 891,109 777,857 12.71 1.41 60,807 4,977,888 5,038,695 3 Memphis 939,094 806,713 14.10 1.30 56,166 4,825,388 4,881,554 4 Baltimore 1,001,871 845,071 15.65 1.29 55,642 5,172,960 5,228,602 6 Helena 1,067,193 892,747 16.35 1.35 58,327 4,990,888 5,049,215 9.0 Renewable Energy—Photovoltaic Panels Photovoltaic panels were modeled with EnergyPlus for Std. 189.1-2009 to comply with the annual on-site renewable energy requirements which are presented in Table 7. The major difference between Standards 189.1-2009 and 189.1-2011 is the area multiplier. In Std. 189.1-2009 the area multiplier is the conditioned space but was changed in Std. 189.1-2011 to be the total roof area, see Table 8. This change has no impact for one story buildings but has a major impact on multi-story buildings such as those being analyzed in this project, see Table 9. The next requirement in determining the PV first cost was to calculate the number of PV panels required for each building type in each city. An analysis was completed using the PVWatts calculator developed by NREL which is readily available at their internet web site. The results for a 4 kW panel are presented in Table 10. Using the energy performance of an individual panel, the number of panels required can be calculated as well as their total first costs. A 4 kW DC panel was assumed to have a de-rated factor of 0.77 which would produce 3.1 kW AC. Goodman reported the cost in 2010 for PV systems as $4.59/W for commercial roof top installations. However, the costs have been steadily decreasing. A realistic estimate for 2012 per Eric Bonnema of NREL is $4.00/W so this value was used for this analysis. Thus, the total cost for a 4 kW panel is $16,000. Using this price the total panel costs and the building costs per square foot can be calculated. The modeling of Std. 189.1-2009 (Liu) used the high efficiency HVAC requirements, see Table 11. For purposes of this study the energy savings and first costs for Std. 189.1-2011 also assumed the high efficiency HVAC requirement, see Table 12. Table 7 Annual On-Site Renewable Energy Criteria Standard Criteria 189.1-2009 189.1-2011 Prescriptive Criteria 6.0 kBtu/ft2 (20 kWh/m2) Single Story Buildings (7.4.1.1) × Conditioned Space Floor Area = 6.0 kBtu/ft2 (20 kWh/m2) × Total Roof Area All Other Buildings = 10.0 kBtu/ft2 (32 kWh/m2) × Total Roof Area HVAC High Efficiency 4.0 kBtu/ft2 (13 kWh/m2) Single Story Buildings Modification (7.4.3.1) x Conditioned Space Floor Area = 4.0 kBtu/ft2 (13 kWh/m2) × Total Roof Area All Other Buildings = 7.0 kBtu/ft2 (22 kWh/m2) × Total Roof Area 80

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172 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD Table 8 Conditioned Space and Roof Areas Area Medium Office Small Hotel Conditioned space 53,660 ft2 (4,985 m2) 43,200 ft2 (4,013 m2) Roof 17,867 ft2 (1,660 m2) 10,800 ft2 (1,003 m2) Table 9 Annual On-Site Renewable Energy Criteria Medium Small Hotel Code Requirement Office (kWh) (kWh) Std. 189.1-2009 99,700 80,260 Std. 189.1-2009—High-Efficiency HVAC 64,805 52,169 Std. 189.1-2011 53,120 32,096 Std. 189.1-2011—High-Efficiency HVAC 36,520 22,066 Table 10 PV Panels Energy Performance Solar Radiation 4 kW DC produces CZ City (kWh/m2-day) annual AC (kWh) 1 Miami 5.26 5,357 2 Phoenix 6.57 6,468 3 Memphis 5.18 5,352 4 Baltimore 4.66 4,911 6 Helena 4.71 5,040 Table 11 Annual On-Site Renewable Energy—Standard 189.1-2009 Medium Office Small Hotel Energy Panels FC FC Energy Panels FC FC CZ City (kWh) (No.) ($) ($/ft2) (kWh) (No.) ($) ($/ft2) 1 Miami 62,847 11.73 187,708 4.35 50,619 9.45 151,186 2.82 2 Phoenix 62,767 9.70 155,268 3.59 50,619 7.83 125,217 2.34 3 Memphis 62,750 11.72 187,593 4.34 50,619 9.46 151,327 2.82 4 Baltimore 62,842 12.80 204,739 4.74 50,619 10.31 164,916 3.08 6 Helena 62,561 12.41 198,606 4.60 50,619 10.04 160,695 3.00 81

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APPENDIX C 173 Table 12 Annual On-Site Renewable Energy—Standard 189.1-2011 Medium Office—36,520 kWh Small Hotel—22,066 kWh Panel FC FC Panel FC FC CZ City (No.) ($) ($/ft2) (No.) ($) ($/ft2) 1 Miami 6.82 109,076 2.52 4.12 65,906 1.23 2 Phoenix 5.65 90,340 2.09 3.41 54,585 1.02 3 Memphis 6.82 109,178 2.53 4.12 65,967 1.23 4 Baltimore 7.44 118,982 2.75 4.49 71,891 1.34 6 Helena 7.25 115,937 2.68 4.38 70,051 1.31 10.0 First Costs—Standard 189.1-2011 The data available for this study included an energy analysis for Std. 189.1-2009 but nothing for Std. 189.1-2011. No data on first costs for either standard was available so it had to be estimated. The starting point was to identify the major differences in the criteria between Standards 189.1-2009 and 189.1-2011. Many features were the same between these two standards including all of envelope criteria plus the HVAC and SWH equipment efficiencies. There were two differences that were explicitly accounted for in this study, the interior lighting power and PV requirements. The first costs for Std. 189.1-2011 include all of the building envelope, lighting and equipment upgrades plus the first costs for the PV system. In order to determine the building first costs the building energy is required. The building energy was calculated using Eq. 1. Energy of 189.1-2011 = Energy of 189.1-2009 − Int. Ltg. 189.1-2009 + Int. Ltg. of 90.1-2010 × LPD Factor in 189.1-2011. (1) In Standard 189.1-2011 Table 7.4.6.1A LPD Factors when Using the Building Area Method lists the LPD Factor of 0.95 for offices and 1.00 for hotels. It is important to note that the energy use associated with the interior lighting has been accounted for directly. However, the impact of the reduced lighting energy will increase the heating loads and reduce the cooling loads in the building but that has not been included. The first costs for Standard 189.1-2011 are presented in Tables 13 and 14. The energy listed for Standards 90.1-2004 and 189.1-2011 is the total site energy for the building with the gas usage converted into kWh. Table 13 Standard 189.1-2011 Medium Office First Costs 90.1- 189.1- Building 2004 2011 Incremental PV 90.1-2004 189.1-2011 Energy Energy Save FC FC FC Baseline Total CZ City (kWh) (kWh) (%) ($/ft2) ($) ($) ($) ($) 1 Miami 802,795 623,508 22.3 1.55 83,009 109,076 6,052,000 6,244,085 2 Phoenix 805,658 605,325 24.9 1.81 96,895 187,235 5,970,500 6,157,735 3 Memphis 788,061 598,540 24.1 2.27 121,618 230,796 5,754,000 5,984,796 4 Baltimore 823,329 619,554 24.8 2.11 113,292 232,274 6,273,000 6,505,274 6 Helena 856,362 652,357 38.9 2.05 109,802 225,739 5,944,500 6,170,239 82

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174 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD Table 14 Standard 189.1-2011 Small Hotel First Costs 90.1- 189.1- Building 2004 2011 Incremental PV 90.1-2004 189.1-2011 Energy Energy Save FC FC FC CZ City (kWh) (kWh) (%) ($/ft2) ($) ($) Baseline ($) Total ($) 1 Miami 905,411 733,948 18.9 2.10 156,797 65,906 5,049,888 5,206,685 2 Phoenix 891,109 727,481 18.4 2.03 142,398 54,585 4,977,888 5,120,286 3 Memphis 939,094 727,860 22.5 2.07 159,559 65,967 4,825,388 4,980,947 4 Baltimore 1,001,871 738,893 26.2 2.16 165,328 71,891 5,172,960 5,338,288 6 Helena 1,067,193 765,549 28.3 2.33 170,788 70,051 4,990,888 5,161,676 11.0 Summary Tables 15 and 16 present the Standard 90.1-2010 and 189.1-2011 first costs and site energy consumptions for both building types so all of the information is conveniently located and summarized for quick reference. The analysis used to develop these first costs and energy consumptions has required many simplifying assumptions. The fundamental approach was to assume a linear relationship between the first costs and the energy savings. Fortunately the energy savings of the AEDG exceeded that of Standards 90.1-2010 and 189.1-2011 so all of the first costs were interpolated and did not need to be extrapolated, see Table 17. An estimate of the first costs and energy savings for Standard 90.1-2010 and 189.1-2011 has been completed. A simplified linear approach was used to determine the results since no reports have been published that contain the required data. Two major differences between the standards were specifically analyzed, the interior lighting power densities and the annual on-site renewable energy requirements. While the direct energy consumption of the interior lights was analyzed the impact of the reduced lighting power was not accounted for in terms of increasing the heating loads and reducing the cool loads. Correct modeling of the interactions was beyond the scope of this project and is best done thorough detailed hourly simulation models such as EnergyPlus. All of the results presented in Tables 16 and 17 include the energy consumptions associated with the interior equipment in each of the buildings. Interior equipment refers to any electrical device that plugs into an outlet (typically not hard wired) and any interior process loads. Plug loads in offices would include computers, monitors, printers, copy machines, vending machines, refrigerators, coffee makers, and desk lamps for task lighting. In addition, hotels would also have televisions, microwave, hair dryers, table and floor lamps in each guest room. Process loads include the clothes washers and dryers in hotels. Table 18 is the summary of the interior equipment energy consumptions that were modeled in the EnergyPlus simulations. Table 15 Summary of Results for Standard 90.1-2010 Medium Office Small Hotel FC Elec. Gas FC Elec. Gas CZ City ($) (kWh) (Mcf) ($) (kWh) (Mcf) 1 Miami 6,141,801 575,130 113 5,104,092 584,536 724 2 Phoenix 6,067,956 563,558 135 5,038,695 543,719 776 3 Memphis 5,895,711 507,455 196 4,881,554 516,889 960 4 Baltimore 6,408,714 474,919 345 5,228,602 498,256 1149 6 Helena 6,021,972 465,091 518 5,049,215 478,914 1371 83

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APPENDIX C 175 Table 16 Summary of Results for Standard 189.1-2011 Medium Office Small Hotel FC Elec. Gas FC Elec. Gas CZ City ($) (kWh) (Mcf) ($) (kWh) (Mcf) 1 Miami 6,244,085 588,664 117 5,206,685 517,411 718 2 Phoenix 6,157,735 561,436 145 5,120,286 496,353 766 3 Memphis 5,984,796 509,573 293 4,980,947 471,153 851 4 Baltimore 6,505,274 484,121 449 5,338,288 456,958 934 6 Helena 6,170,239 466,415 616 5,161,676 440,558 1077 Table 17 Range of Energy Savings (%) Document Medium Office Small Hotel AEDG 42-53 27-34 Std. 90.1-2010 24-30 11-16 Std. 189.1-2011 22-39 19-28 Table 18 Interior Equipment Energy Consumptions Medium Office Small Hotel Standard kWh Mcf kWh Mcf 90.1-2010 211,799 0 164,169 388 189.1-2011 235,822 0 158,386 388 12.0 References ASHRAE. (2004). ANSI/ASHRAE/IESNA Standard 90.1-2004: Energy Standard for Buildings Except Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers. ASHRAE. (2009). ANSI/ASHRAE/USGBC/IES Standard 189.1-2009: Standard for the Design of High- Performance Green Buildings Except Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers. ASHRAE. (2010). ANSI/ASHRAE/IESNA Standard 90.1-2010: Energy Standard for Buildings Except Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers. ASHRAE. (2011). ANSI/ASHRAE/USGBC/IES Standard 189.1-2011: Standard for the Design of High- Performance Green Buildings Except Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers. Crawley, D.B., L.K. Lawrie, F.C. Winkelmann, W.F. Buhl, Y.J. Huang, C.O. Pedersen, R.K. Strand, R.J. Liesen, D.E. Fisher, M.J. Witte, J. Glazer. (2001). EnergyPlus: Creating a New-Generation Building Energy Simulation Program. Energy and Buildings 33:319-331. Amsterdam: Elsevier Science. Goodrich, A., T. James, M. Woodhouse. (2012). Residential, Commercial, and Utility-Scale Opportunities. Golden, CO: National Renewable Energy Laboratory, Technical Report Photovoltaic (PV) System Prices in the United States: Current Drivers and Cost-Reduction NREL/TP-6A20-53347. 84

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176 ENERGY-EFFICIENCY STANDARDS AND GREEN BUILDING CERTIFICATION SYSTEMS USED BY THE DOD Jaing, W. R.E. Jarnagin, K. Gowri, M. McBride, B. Liu. (2008). Technical Support Document: The Development of the Advanced Energy Design Guide for Highway Lodging Buildings. Richland, WA: Pacific Northwest National Laboratory, PNNL-17875. Liu, B. and J. Zhang. (2011). 189.1 Progress Indicator Report: Energy Use Comparison between 189.1- 2009 and 90.1-2010. ASHRAE Standard 189.1 Committee, ASHRAE Annual Meeting, June 29, 2011, Montreal, Canada. Long, N., E. Bonnema, K. Field, and P. Torcellini. (2010). Evaluation of ANSI/ASHRAE/USGBC/IES Standard 189.1-2009. Golden, CO: National Renewable Energy Laboratory, Technical Report NREL/TP-550-47906. Thornton, B.A., W. Wang, M.D. Lane, M.I. Rosenberg, B. Liu. (2009). Technical Support Document: 50% Energy Savings Design Technology Packages for Medium Office Buildings. Richland, WA: Pacific Northwest National Laboratory, PNNL-19004. Thornton, B.A., M.I. Rosenberg, E.E. Richman, W. Wang, Y. Xie, J. Zhang, H. Cho, V.V. Mendon, R.A. Athalye, B. Liu. (2011). Achieving the 30% Goal: Energy and Cost Savings Analysis of ASHRAE Standard 90.1-2010. Richland, WA: Pacific Northwest National Laboratory, PNNL-20405. 13.0 Web Sites PVWatts: www.nrel.gov/rredc/pvwatts. ASHRAE DATA METHODOLOGY: WATER USE ANALYSIS The following is a summary of water use savings estimates made by WMI. The starting point for all of the estimates was the water use given in the data temples. Plumbing Fixtures To calculate the saving for plumbing fixture related measures WMI uses a model that considers multiple factors. The number, type, and flow rate of the existing fixtures help us to determine the overall existing condition of the domestic fixtures. Often, the fixture flow rates differ from the designed flow rates. For example, many 1.6 gpf toilets fitted with 1.6 gpf diaphragm flushometers typically use between 1.8 and 2.5 gpf. Once existing flow rates are determined, frequency of usage is then calculated based on building demographic information. Usage is affected by many factors: the population of a facility, the hours of use, the average number of times a person will use the facilities. Another factor is the split of the population between male and female. Studies have shown that on the average people need to use the toilets an average of once every two hours and when available, men will use the urinals about 75% of the time. The basic formula is as follows: Existing usage model = Population × uses per day (decreased by the flush factor) × days of use per year × the average existing flow rates of the fixtures. Post-program usage model = Population × uses per day (decreased by the flush factor) × days of use per year × the average proposed flow rates of the fixtures. 85

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APPENDIX C 177 Showers are also included in the hotel template calculations. These were based on an average of sampled flow rates for showers in hotels throughout the U.S. and usage was calculated using a conservative shower duration length of 8 minutes per shower. The post-program annual gallons saved = the difference between the two. ASHRAE 189.1 was used as the basis for efficient plumbing fixture selection and use. Landscape Water use for landscape irrigation in high performance landscapes is based on proper selection of plant material, proper soil preparation, and watering based on the actual needs of the plant material in the landscape. The basic principles of good landscape water practices include: 1. Design Landscape to keep water (rainwater, storm water, and irrigation water) where it falls. 2. Prepare soil shape and content to capture and hold water 3. Design landscape to minimize the need for irrigation water (eliminate irrigation systems where possible) 4. Minimize turf areas and choose adapted and drought tolerant plant materials 5. Meter or sub-meter installed irrigation systems 6. Capture and use on-site sources of water and/or reclaimed water 7. Design efficient irrigation system using US EPA WaterSense principles 8. Practice proper maintenance. Water use is based on evapotranspiration of the plant material actually used. The equation is: Water Demand = [Area of landscape × (ETo × Kc) − Effective rainfall)] × [FF] × 0.623 DU • ETo—Reference evapotranspiration • Kc—Crop Coefficient • Effective rainfall—assume 25% (WaterSense) • DU—Distribution Uniformity • FF—Freeze factor when system off in Winter • 0.623—Gallons per inch on one square foot of area Monthly evapotranspiration for each site was taken into consideration along with plant material and practices common to those areas. Savings were based on the difference between the amounts of water given in the data templates and the water use based on good practice for all of the eight principles outlined above. These principles are reflected in ASHRAE 189.1 86