PNNL-23824 National Cost-effectiveness of ANSI/ASHRAE/IES Standard 90.1-2013 January 2015 R Hart SA Loper EE Richman RA Athalye MI Rosenberg MA Halverson Y Xie PNNL - 23824 National Cost-effectiveness of ANSI/ASHRAE/IES Standard 90.1- 2013 R Hart SA Loper EE Richman RA Athalye MI Rosenberg MA Halverson Y Xie January 2015 Prepared for The U.S. Department of Energy under Contract DE-AC05-76RL01830 Pacific Northwest National Laboratory Richland, Washington 99352 Executive Summary The U.S. Department of Energy (DOE) Building Energy Codes Program supports the upgrade and implementation of building energy codes and standards, which set minimum requirements for energy- efficient design and construction for new and renovated buildings, and impact energy use and greenhouse gas emissions for the life of buildings. Continuous improvement of building energy efficiency is achieved by periodically updating model energy codes for commercial and residential buildings. Through consensus-based code development processes, DOE recommends revisions and amendments, supporting technologically feasible and economically justified energy efficiency measures. Ensuring that model code changes impacting the cost of building construction, maintenance, and energy services are cost-effective also encourages their adoption and implementation at the state and local levels. Pacific Northwest National Laboratory (PNNL) prepared this analysis to support DOE in evaluating the energy and economic impacts associated with updated codes in commercial buildings. The purpose of this analysis is to examine the cost-effectiveness of the 2013 edition of ANSI/ASHRAE/IES1 Standard 90.1 (ANSI/ASHRAE/IES 2013). Standard 90.1 is developed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard Standing Project Committee (SSPC) 90.1. It is the model energy standard for commercial and multi- family residential buildings over three floors (42 USC 6833). PNNL analyzed the cost-effectiveness of changes in Standard 90.1 from 90.1-2010 to 90.1-2013, as applied in commercial buildings across the United States. During the development of new editions of Standard 90.1, the cost-effectiveness of individual changes (addenda) is often calculated to support the deliberations of ASHRAE Standard Standing Project Committee (SSPC) 90.1. The ASHRAE process, however, does not include analysis of the cost-effectiveness of the entire package of addenda from one edition of the standard to the next, which is of particular interest to adopting State and local governments. Providing States with an analysis of cost- effectiveness may encourage more rapid adoption of newer editions of energy codes based on Standard 90.1. This information may also inform the development of future editions of Standard 90.1. To establish the cost-effectiveness of Standard 90.1-2013, three main tasks were addressed: • Identification of building elements impacted by the updated standard • Allocation of associated installation, maintenance, and replacement costs • Cost-effectiveness analysis of required changes In addition to installation, maintenance, and replacement costs, energy cost differences were needed to determine cost-effectiveness. The energy costs for each edition of Standard 90.1 were determined previously under the development of Standard 90.1-2013, as described below. The current analysis builds on the previous PNNL analysis (as outlined in Section 5.2) of the energy use and energy cost saving impacts of Standard 90.1-2013 compared to previous editions. The overall energy savings analysis of Standard 90.1 utilized a suite of 16 prototype EnergyPlus building models in 15 climate locations representing all eight U.S. climate zones. Detailed methodology and overall energy 1 ANSI – American National Standards Institute; ASHRAE – American Society of Heating, Refrigerating, and Air- Conditioning Engineers; IES – Illuminating Engineering Society; IESNA – Illuminating Engineering Society of North America ( IESNA rather than IES was identified with Standard 90.1 prior to 90.1-2010) iii saving results from Standard 90.1-2013 are documented in the PNNL technical report titled ANSI/ASHRAE/IES Standard 90.1-2013 Determination of Energy Savings: Quantitative Analysis (Halverson et al. 2014). The cost-effectiveness analysis in this report used a subset of prototypes and climate locations, providing coverage of nearly all of the changes in Standard 90.1 from the 2010 to 2013 edition that affect energy savings, equipment and construction costs, and maintenance, including conventional HVAC systems used in commercial buildings. The changes included and excluded are described in Section 3.0. The following prototype buildings and climate locations were selected for the analysis, using the rationale described in Section 2.1: Prototype Buildings Climate Locations Small Office 2A Houston, Texas (hot, humid) Large Office 3A Memphis, Tennessee (warm, humid) Standalone Retail 3B El Paso, Texas (hot, dry) Primary School 4A Baltimore, Maryland (mixed, humid) Small Hotel 5A Chicago, Illinois (cool, humid) Mid-rise Apartment The subset of selected prototypes represents the energy impact of five of the eight commercial principal building activities that account for 74% of the new construction by floor area. Each of the 6 selected prototype buildings was analyzed in the 5 selected climate locations for a total of 30 cost- effectiveness assessments. A primary input to the cost-effectiveness analysis was the incremental costs for the addenda to Standard 90.1-2010 that were included in Standard 90.1-2013. Of the 110 total addenda to 90.1-2010, 33 were found to have quantified energy savings that could be modeled in the 90.1-2013 energy savings analysis. The remaining addenda were not considered to have quantifiable energy savings, or did not directly affect building energy usage. Of the addenda with quantified energy savings, 28 were modeled in the six prototypes at the five climate locations and were included with the cost estimate. The remaining five addenda affect prototypes that were not included in the cost-effectiveness analysis, and are not expected to have a significant impact on the cost-effectiveness as described in Section 3.0. The methodology for cost-effectiveness assessments has been established1 for analysis of prior editions of Standard 90.1 (Hart and Liu 2015). Three economic metrics are used in this report: • Life-cycle cost analysis (LCCA) • SSPC 90.1 Scalar Method • Simple payback Table ES.1 summarizes the cost-effectiveness results. Findings demonstrate that the 2013 edition of Standard 90.1 is cost-effective overall relative to the 2010 edition under the LCCA and modified SSPC 90.1 Scalar Method for the representative prototypes and climate locations. 1 See methodology at: http://www.energycodes.gov/development/commercial/methodology. iv Table ES.1. Summary of Cost-effectiveness Analysis Climate Zone and Location Prototype 2A Houston 3A Memphis 3B El Paso 4A Baltimore 5A Chicago Life Cycle Cost Net Savings Small Office Total $21,600 $15,200 $10,800 $2,900 $5,000 $/ft2 $3.93 $2.76 $1.96 $0.53 $0.91 Large Office Total $740,000 $1,650,000 $2,540,000 $300,000 $1,340,000 $/ft2 $1.48 $3.31 $5.09 $0.60 $2.69 Standalone Retail Total $84,000 $81,400 $53,800 $67,000 $79,000 $/ft2 $3.40 $3.30 $2.18 $2.71 $3.20 Primary School Total $246,000 $116,000 $398,000 $70,000 $54,000 $/ft2 $3.33 $1.57 $5.38 $0.95 $0.73 Small Hotel Total $96,410 $76,000 $78,000 $62,600 $57,000 $/ft2 $2.23 $1.76 $1.81 $1.45 $1.32 Mid-rise Apartment Total $59,600 $22,600 $23,800 $29,200 $28,500 $/ft2 $1.77 $0.67 $0.71 $0.87 $0.84 Simple Payback (years) Small Office Immediate Immediate Immediate 22.0 17.0 Large Office 6.8 Immediate Immediate 5.1 Immediate Standalone Retail Immediate Immediate Immediate Immediate Immediate Primary School 5.5 9.5 0.6 14.3 15.6 Small Hotel 3.9 4.1 4.0 7.2 8.7 Mid-rise Apartment 1.9 11.7 11.4 7.2 9.7 Scalar Ratio, Limit = 21.85 Small Office (4.9) (2.8) (6.3) 20.0 15.1 Large Office 5.6 (44.7) (53.7) 3.0 (86.8) Standalone Retail (1.9) (1.6) (2.0) 4.2 3.8 Primary School 5.1 11.1 (1.2) 15.3 16.7 Small Hotel 3.8 4.5 4.4 7.5 8.9 Mid-rise Apartment 2.2 11.3 11.1 7.0 9.5 v Acknowledgments This report was prepared by Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy (DOE) Building Energy Codes Program. The authors would like to thank David Cohan, Jeremy Williams, and Mohammed Khan at DOE for providing oversight. The authors would like to thank the members of the ASHRAE Standing Standards Project Committee (SSPC) for 90.1 for their review of the cost estimates. The authors also recognize Bing Liu, Manager of the Building Energy Codes Program at PNNL. This work was truly a team effort, and the authors would like to express their deep appreciation to everyone from the PNNL codes team who contributed to its completion, including Jing Wei Zhuge, Jian Zhang, Weimin Wang, and Rosemarie Bartlett. Reid Hart, PE Pacific Northwest National Laboratory vii