Security check
Please login to your personal account to use this feature.
Please login to your authorized staff account to use this feature.
Are you sure you want to empty the cart?
, 2024
- ASHRAE Online Bookstore
- Climate Analysis Data Sources
- Addenda
- Errata
- Return to Previous Page
- ANSI/ASHRAE/IBPSA Standard 209-2024 [Go to Page]
- Contents
- Foreword
- 1. Purpose
- 2. Scope
- 3. Definitions, Abbreviations, and Acronyms [Go to Page]
- 3.1 General
- 3.2 Definitions
- 3.3 Abbreviations and Acronyms
- 4. Utilization [Go to Page]
- 4.1 Timing of Work. The energy modeler shall perform energy modeling at each phase of the planning, design, and construction or operation of the building as specified in the owner’s project requirements (OPR) or in the owner/energy modeler agreemen...
- 4.2 Compliance
- 5. General Requirements [Go to Page]
- 5.1 Simulation Software Requirements. Whole-building simulation software used to comply with the standard shall meet the minimum requirements of ASHRAE/IES Standard 90.1,1 Section G2.2.
- 5.2 Modeler Qualifications. The energy modeler or the individual supervising the work of the energy modeler shall have completed a minimum of five energy modeling projects, and at least one of the following:
- 5.3 Climate and Site Analysis
- 5.4 Benchmarking. Determine the energy use per unit area of buildings with the same principal building activities in the same climate and determine their annual energy costs per unit area by applying local utility rates. These data shall be used in t...
- 5.5 Charrette
- 5.6 Performance Goals in Owner’s Project Requirements
- 5.7 General Modeling Cycle Requirements. This section lists requirements that are common to all of the modeling cycles included within the standard. Cycle-specific requirements are included in their respective sections.
- 6. Design Modeling Cycles [Go to Page]
- 6.1 Modeling Cycle # 1—Simple Box Modeling
- 6.2 Modeling Cycle #2—Conceptual Design Modeling
- 6.3 Modeling Cycle #3—Load Reduction Modeling
- 6.4 Modeling Cycle #4—HVAC System Selection Modeling
- 6.5 Modeling Cycle #5—Design Refinement
- 6.6 Modeling Cycle #6—Design Integration and Optimization
- 6.7 Modeling Cycle #7—Responsive Design Alternative Modeling
- 7. Construction and Operations Modeling [Go to Page]
- 7.1 Modeling Cycle #8—As-Designed Energy Performance
- 7.2 Modeling Cycle #9—Change Orders
- 7.3 Modeling Cycle #10—As-Built Energy Performance
- 8. Operational Modeling [Go to Page]
- 8.1 Modeling Cycle #11—Operational Energy Performance Comparison
- 9. Normative References
- Informative Appendix A: Climate Information [Go to Page]
- A1. General Information Resources
- A2. Climate Data Resources
- Informative Appendix B: Benchmark Information [Go to Page]
- B1. General Information Resources
- Informative Appendix C: Modeling Input for Simple Box and Other Cycles [Go to Page]
- C1. Informative Resources
- Informative Appendix D: Owner’s Project Requirements
- Informative Appendix E: Quality Assurance and Quality Control Checklists
- Informative Appendix F: Future Climate Analysis [Go to Page]
- F1. Overview of Climate Modeling Techniques [Go to Page]
- F1.1 The Representative Concentration Pathway—Shared Socioeconomic Pathway (RCP-SSP) Framework. In climate research, scenarios are alternative descriptions of how the future might evolve and are an important tool for analyzing how driving forces ma...
- F1.2 Projection of Future Climate. General circulation models (GCMs) are used as the primary tool to project the evolution of climate. They simulate the movement of mass and energy in the atmosphere and the ocean by using a system of mathematical equ...
- F1.3 Downscaling. GCMs have a typical spatial resolution of 62 to 124 mi (100 to 200 km) to stay within the computational limits of modern supercomputers. Physical processes at a scale finer than the grid size cannot be explicitly resolved and must b...
- F1.4 Different Types of Future Weather Data
- F2. Application Scenarios of Future Weather Data
- F3. Sources of Future Weather Data
- F4. Interpretation of Results
- Informative Appendix G: Predictive Energy Modeling [Go to Page]
- G1. Introduction
- G2. Defining a Goal
- G3. Uses for Predictive Modeling
- G4. Predictive Modeling Considerations [Go to Page]
- G4.1 Weather. Selecting a weather file should be carefully considered for predictive modeling. Projects should choose weather from nearby stations with similar microclimates (such as elevation or proximity to large bodies of water). Projects with a g...
- G4.2 Occupant Behavior. Comparative analysis often uses typical schedules for the major building uses. This approach may have all private offices set to 10% occupancy during a specific time period, when a more nuanced schedule would have one out of e...
- G4.3 Uncertain Loads. Some loads are challenging to predict during modeling. Plug loads may vary as staff change their workstation setups, infiltration depends on the details and rigor of the installation methods, and HVAC equipment may be improperly...
- G4.4 Overlooked Loads. Energy modeling for compliance can sometimes overlook loads that are not regulated by energy codes, such as ANS/ASHRAE/IES Standard 90.1,1 but fall within the energy boundary of interest. Predictive energy modeling needs to acc...
- G4.5 Sensitivity Analysis. While for some applications of building energy modeling (e.g., code compliance) it is convenient to yield consistent deterministic results, there are applications (see Section G3, “Uses of Predictive Modeling”) where it...
- G4.6 Documenting Existing Conditions. Retrofits of existing buildings present numerous challenges, especially in documenting existing conditions. To establish existing conditions, a field survey is often required, taking more time than in new buildin...
- G4.7 Calculation Uncertainty. Beyond the uncertainty of input values discussed previously, there is also uncertainty due to the algorithms used by the simulation engines not perfectly matching real-world performance. A full discussion of calculation ...
- G4.8 Project Process and Team Member Implications. With aggressive efficiency targets, early and regular energy analysis is critical to determining a cost-effective path to achieving the project’s performance target. Prerequisites in Standard 209, ...
- G5. Renewable Energy
- G6. Storage
- G7. Demand Response
- Informative Appendix H: Guidance in Design
- Informative Appendix I: Level of Detail for Model Inputs [Go to Page]
- I1 Modeling Cycle #1—Simple Box Modeling
- I2. Modeling Cycle #2—Conceptual Design Modeling
- I3. Modeling Cycle #3—Load Reduction Modeling
- I4. Modeling Cycle #4—HVAC System Selection Modeling
- I5. Cycle #5—Design Refinement
- I6. Modeling Cycle #6—Design Integration and Optimization
- I7. Modeling Cycle #7—Responsive Design Alternative Modeling
- Informative Appendix J: Informative References and Bibliography
- Informative Appendix K: Addenda Description [Go to Page]
