Technical Guidelines for Multifamily Building Energy Audits, April 2015

201 Pages·2015·5.91 MB·English

TECHNICAL GUIDELINES FOR
MULTIFAMILY BUILDING ENERGY AUDITS

Michael MacDonald

With contributions from

Mark Ternes
Mini Malhotra
Oak Ridge National Laboratory

Date Published: April 2015

Based on a Draft Report Prepared for
OAK RIDGE NATIONAL LABORATORY
Oak Ridge, Tennessee
And the
US DEPARTMENT OF ENERGY

Contents
Page
List of Figures .............................................................................................................................................. ix 
List of Tables ............................................................................................................................................... xi 
Foreword .................................................................................................................................................... xiii 
Use Considerations .................................................................................................................................... xiii 
Acknowledgements .................................................................................................................................... xiii 
Contributors ............................................................................................................................................... xiv 
Preface: Measures Table ............................................................................................................................ xiv 
1.  Introduction ........................................................................................................................................ 1-1 
1.1  Multifamily Building Population Data .................................................................................... 1-1 
1.2  Multifamily Building Energy Audit Objectives and Levels .................................................... 1-2 
1.3  Multifamily Building Energy Audit Work Flow Process ........................................................ 1-2 
1.4  Energy Auditor Qualifications and Responsibilities ................................................................ 1-4 
1.5  Scope of the Report .................................................................................................................. 1-5 
1.6  How to Use this Report ............................................................................................................ 1-5 
1.7  Resources ................................................................................................................................. 1-5 
2.  Pre-Site Visit Activity ........................................................................................................................ 2-1 
2.1  Owner Interviews ..................................................................................................................... 2-1 
2.2  Stakeholder Meeting ................................................................................................................ 2-3 
2.3  Historical Preservation ............................................................................................................. 2-3 
2.4  Basic Building Data Collection and Analysis .......................................................................... 2-4 
2.4.1  Building Data .............................................................................................................. 2-4 
2.4.2  Space Types ................................................................................................................ 2-5 
2.4.3  Site Plan and Diagrams ............................................................................................... 2-5 
2.5  Sampling Plan and Requirements ............................................................................................ 2-6 
2.5.1  Uncertainty .................................................................................................................. 2-7 
2.5.2  Requirements in the Plan ............................................................................................ 2-7 
2.5.3  Individual Buildings .................................................................................................... 2-7 
2.5.4  Multiple Building Sites ............................................................................................... 2-9 
2.6  Energy Use Data ...................................................................................................................... 2-9 
2.6.1  Utility Data................................................................................................................ 2-10 
2.6.2  Utility Bill Requirements .......................................................................................... 2-10 
2.6.3  Sampling of Units ..................................................................................................... 2-11 
2.6.4  Utility Bill Review .................................................................................................... 2-12 
2.6.5  Bulk Fuels ................................................................................................................. 2-12 
2.7  Water Use and Other Utility Analysis ................................................................................... 2-12 
2.8  Preliminary Energy Analysis ................................................................................................. 2-12 
2.8.1  Whole-Building Energy Benchmarking .................................................................... 2-13 
2.8.2  Disaggregation of End Uses ...................................................................................... 2-20 
2.9  References .............................................................................................................................. 2-23 
3.  Site Visit ............................................................................................................................................ 3-1 
3.1  Data Collection Forms and Itemized Standards ....................................................................... 3-2 
3.2  Verifying and Updating Data ................................................................................................... 3-2 
3.3  Inspection, Testing, and Analysis ............................................................................................ 3-3 
3.3.1  Maintenance Staff Interviews and Their Importance .................................................. 3-3 
3.3.2  Sampling Analysis ...................................................................................................... 3-4 
3.4  Resident Interviews .................................................................................................................. 3-5 
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3.5  Tools and Functional Roles ...................................................................................................... 3-6 
3.5.1  Tools ........................................................................................................................... 3-6 
3.5.2  Functional Roles ......................................................................................................... 3-6 
3.6  References ................................................................................................................................ 3-7 
4.  Post–Site Visit Modeling and Data Analysis ..................................................................................... 4-1 
4.1  The IPMVP and Determination of Energy Savings ................................................................. 4-1 
4.2  Level of Energy Audit.............................................................................................................. 4-2 
4.3  Whole-Building Detailed Simulation Base-Case Model ......................................................... 4-3 
4.4  Understanding ECM Analysis Tools ....................................................................................... 4-4 
4.5  Understanding Complex Simulation Programs and Calibration .............................................. 4-5 
4.5.1  Use of Shading Devices .............................................................................................. 4-5 
4.5.2  Power Densities and Schedules ................................................................................... 4-6 
4.5.3  Infiltration, Ventilation, and Exhaust Flows ............................................................... 4-8 
4.5.4  Heating and Cooling Efficiencies and Controls .......................................................... 4-8 
4.5.5  Indoor Temperatures ................................................................................................... 4-9 
4.5.6  Fluid-Moving Systems ................................................................................................ 4-9 
4.5.7  Final Calibration ......................................................................................................... 4-9 
4.6  Savings Evaluation ................................................................................................................... 4-9 
4.7  Additional Analyses ............................................................................................................... 4-10 
4.8  References .............................................................................................................................. 4-10 
5.  Work Scope, Audit Report, and Next Steps ...................................................................................... 5-1 
5.1  Energy Upgrade Process and Scope of this Report .................................................................. 5-2 
5.2  Energy Audit Report ................................................................................................................ 5-2 
5.2.1  Recommended Measures and Measure Packages ....................................................... 5-3 
5.2.2  Basic Report Outline ................................................................................................... 5-3 
5.3  Work Scope Generation ........................................................................................................... 5-4 
5.4  Next Steps in the Energy Upgrade Process .............................................................................. 5-5 
5.5  References ................................................................................................................................ 5-6 
6.  Appliances, Lighting, and Other Equipment ..................................................................................... 6-1 
6.1  Understanding Baseloads ......................................................................................................... 6-1 
6.1.1  Baseload Resources .................................................................................................... 6-3 
6.1.2  Baseload Data from the 2009 RECS ........................................................................... 6-3 
6.2  Occupancy and Staff Impacts .................................................................................................. 6-4 
6.3  Evaluation and Opportunities ................................................................................................... 6-4 
6.3.1  Lighting ....................................................................................................................... 6-4 
6.3.2  Refrigerators ............................................................................................................... 6-6 
6.3.3  Other Appliances and Equipment ............................................................................... 6-6 
6.4  Data Gathering ......................................................................................................................... 6-7 
6.4.1  Lighting ....................................................................................................................... 6-7 
6.4.2  Refrigerators ............................................................................................................... 6-7 
6.4.3  Other Equipment ......................................................................................................... 6-8 
6.5  Challenges, Issues, and Pitfalls ................................................................................................ 6-8 
6.6  Energy Audit Process ............................................................................................................... 6-9 
6.6.1  Lighting ....................................................................................................................... 6-9 
6.6.2  Refrigerators ............................................................................................................. 6-10 
6.6.3  Other Equipment ....................................................................................................... 6-10 
6.7  References .............................................................................................................................. 6-10 
7.  Building Enclosure ............................................................................................................................ 7-1 
7.1  Background and Opportunities Overview ................................................................................ 7-2 
7.1.1  Basic Insulation Measures .......................................................................................... 7-2 
7.1.2  Thermal Bypasses ....................................................................................................... 7-3 
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7.1.3  Airflow ........................................................................................................................ 7-4 
7.1.4  Moisture Transfer ........................................................................................................ 7-6 
7.1.5  Durability and Structural Issues .................................................................................. 7-8 
7.1.6  Windows and Doors .................................................................................................... 7-8 
7.2  Data Gathering ......................................................................................................................... 7-9 
7.2.1  Interviews .................................................................................................................... 7-9 
7.2.2  Inspections and Testing ............................................................................................... 7-9 
7.2.3  Moisture and Water ................................................................................................... 7-11 
7.2.4  Data for Energy Modeling ........................................................................................ 7-11 
7.2.5  Quality of Construction ............................................................................................. 7-12 
7.2.6  Instrumented Diagnostics .......................................................................................... 7-12 
7.3  Challenges, Issues, and Pitfalls .............................................................................................. 7-13 
7.4  Energy Audit Process ............................................................................................................. 7-14 
7.4.1  General Considerations ............................................................................................. 7-14 
7.4.2  Health and Safety Issues ........................................................................................... 7-15 
7.4.3  Air and Vapor Barrier ............................................................................................... 7-15 
7.4.4  Thermal Bypasses, Air Leakage, and Moisture Leakage .......................................... 7-16 
7.4.5  Feasibility of Energy Conservation Measures .......................................................... 7-16 
7.5  Codes and Standards .............................................................................................................. 7-16 
7.6  References .............................................................................................................................. 7-17 
8.  Indoor Air Quality and Ventilation System ....................................................................................... 8-1 
8.1  Low-Rise and High-Rise Differences ...................................................................................... 8-1 
8.2  ASHRAE Standards 62.2 and 62.1 .......................................................................................... 8-2 
8.3  Indoor Air Quality .................................................................................................................... 8-2 
8.4  Multifamily Building IAQ Evaluation ..................................................................................... 8-4 
8.5  Ventilation Systems ................................................................................................................. 8-4 
8.6  Smoke and Fire Control ........................................................................................................... 8-5 
8.7  Data Gathering and Opportunities ........................................................................................... 8-5 
8.7.1  Standard 62.2 Method ................................................................................................. 8-5 
8.7.2  Use of Standard 62.1 in Buildings over Three Stories ................................................ 8-7 
8.7.3  Other Projects .............................................................................................................. 8-7 
8.7.4  Basic Approach ........................................................................................................... 8-7 
8.7.5  Opportunities ............................................................................................................... 8-8 
8.7.6  Data for Energy Modeling .......................................................................................... 8-9 
8.8  Challenges, Issues, and Pitfalls ................................................................................................ 8-9 
8.9  Energy Audit Process ............................................................................................................... 8-9 
8.10  Codes and Standards .............................................................................................................. 8-11 
8.11  Other Resources ..................................................................................................................... 8-11 
8.12  References .............................................................................................................................. 8-11 
9.  Centralized Heating and Cooling ....................................................................................................... 9-1 
9.1  System Background ................................................................................................................. 9-4 
9.1.1  Steam Systems Overview ........................................................................................... 9-4 
9.1.2  Hot Water Systems Overview ..................................................................................... 9-5 
9.1.3  Heat Pump Systems Overview .................................................................................... 9-5 
9.1.4  Chilled Water Systems Overview ............................................................................... 9-6 
9.1.5  Campus and District Steam Systems .......................................................................... 9-6 
9.2  What is Efficiency and What are the Opportunities? ............................................................... 9-7 
9.2.1  Heating Plants ............................................................................................................. 9-7 
9.2.2  Hydronic Heat Pump Systems .................................................................................. 9-10 
9.2.3  Chiller Plants ............................................................................................................. 9-11 
9.3  Energy Audit of Steam Systems ............................................................................................ 9-13 
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9.3.1  Energy Audit Process ................................................................................................ 9-13 
9.3.2  Evaluation and Measurement .................................................................................... 9-14 
9.4  Energy Audit of Hot Water Systems ...................................................................................... 9-23 
9.4.1  Energy Audit Process ................................................................................................ 9-24 
9.4.2  Evaluation and Measurement .................................................................................... 9-25 
9.5  Energy Audit of Hydronic Heat Pump Systems .................................................................... 9-31 
9.6  Energy Audit of Central Chiller Plants .................................................................................. 9-32 
9.7  Thermal Energy Storage and Isolated Zone Heat Pumps ...................................................... 9-34 
9.8  Codes and Standards .............................................................................................................. 9-34 
9.9  Additional Resources ............................................................................................................. 9-34 
9.10  References .............................................................................................................................. 9-34 
10.  Local Heating and Cooling Systems ................................................................................................ 10-1 
10.1  System Populations ................................................................................................................ 10-3 
10.2  System Descriptions ............................................................................................................... 10-3 
10.2.1  Furnaces and Unitary Air Conditioners .................................................................... 10-3 
10.2.2  Heat Pumps ............................................................................................................... 10-4 
10.2.3  Window Air Conditioners ......................................................................................... 10-5 
10.2.4  Other Systems ........................................................................................................... 10-5 
10.3  Evaluation and Opportunities ................................................................................................. 10-6 
10.3.1  Energy Model Space Types ...................................................................................... 10-6 
10.3.2  System Sizing............................................................................................................ 10-6 
10.3.3  Heating Efficiency .................................................................................................... 10-6 
10.3.4  Cooling Efficiency .................................................................................................... 10-8 
10.3.5  Duct Efficiency ......................................................................................................... 10-8 
10.3.6  Fan and Motor Efficiency ....................................................................................... 10-10 
10.3.7  Thermostat Control Impacts.................................................................................... 10-11 
10.3.8  Other Control Options ............................................................................................. 10-11 
10.4  Data Gathering ..................................................................................................................... 10-11 
10.4.1  Fan Motors .............................................................................................................. 10-12 
10.4.2  Ducts ....................................................................................................................... 10-12 
10.4.3  Furnaces .................................................................................................................. 10-13 
10.4.4  Heat Pumps ............................................................................................................. 10-14 
10.4.5  Other Heating Equipment ....................................................................................... 10-14 
10.4.6  Cooling Equipment ................................................................................................. 10-14 
10.4.7  Indoor Temperatures and Thermostats ................................................................... 10-15 
10.5  Challenges, Issues, and Pitfalls ............................................................................................ 10-15 
10.6  Energy Audit Process ........................................................................................................... 10-16 
10.7  Codes and Standards ............................................................................................................ 10-17 
10.8  Other Resources ................................................................................................................... 10-17 
10.9  References ............................................................................................................................ 10-17 
11.  Domestic Hot Water ........................................................................................................................ 11-1 
11.1  Hot Water Loads .................................................................................................................... 11-2 
11.2  Water Heating Systems .......................................................................................................... 11-2 
11.2.1  Heat Generation and Distribution ............................................................................. 11-3 
11.3  Energy Audit Process ............................................................................................................. 11-3 
11.4  Evaluation and Opportunities ................................................................................................. 11-5 
11.5  Data Gathering ....................................................................................................................... 11-7 
11.5.1  Interviews .................................................................................................................. 11-7 
11.5.2  Safety Issues .............................................................................................................. 11-7 
11.5.3  Outlet Water Temperature ........................................................................................ 11-8 
11.5.4  DHW Generation Source and Centralized Devices .................................................. 11-8 
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11.5.5  Centralized Distribution Systems .............................................................................. 11-8 
11.6  Challenges and Special Issues ................................................................................................ 11-9 
11.7  Evaluation Resources ............................................................................................................. 11-9 
11.8  Codes and Standards ............................................................................................................ 11-10 
11.9  References ............................................................................................................................ 11-10 
12.  Special Topics .................................................................................................................................. 12-1 
12.1  Water Conservation................................................................................................................ 12-1 
12.1.1  References ................................................................................................................. 12-2 
12.2  Cold Water Supply ................................................................................................................. 12-2 
12.2.1  Water Quality ............................................................................................................ 12-3 
12.3  Landscape, Irrigation, and Outdoor Water Use ..................................................................... 12-4 
12.3.1  References ................................................................................................................. 12-4 
12.4  Solar Systems ......................................................................................................................... 12-5 
12.4.1  Background and Scope ............................................................................................. 12-5 
12.4.2  Solar Thermal Systems ............................................................................................. 12-5 
12.4.3  Photovoltaic Systems ................................................................................................ 12-6 
12.4.4  Evaluation and Opportunities.................................................................................... 12-7 
12.4.5  Challenges, Issues, and Pitfalls ................................................................................. 12-8 
12.4.6  Codes, Standards, and References ............................................................................ 12-8 
12.5  Swimming Pools .................................................................................................................. 12-10 
12.6  Cogeneration Systems .......................................................................................................... 12-10 
12.6.1  References ............................................................................................................... 12-11 
12.7  Central Campus Systems ..................................................................................................... 12-11 
12.7.1  References ............................................................................................................... 12-12 
12.8  Historical Buildings Issues ................................................................................................... 12-12 
12.8.1  References ............................................................................................................... 12-13 

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