Compliance Modeling is the generic term for energy modeling that will be used to prove a proposed design meets specific performance criteria. Typically the performance criteria comes in the form of energy savings over a baseline design that is prescriptively defined. There are various requirements depending on the local Energy Code or certification (e.g. LEED) and many workflows available. Please refer to this help article for a detailed breakdown of the many workflows the platform can connect to.
In loadmodeling.tool, which uses the powerful whole building simulation engine EnergyPlus compliance energy modeling can be accomplished with the Whole Building Energy Modeling update in version 5.0. Following is a description of how the platform meets common requirements and the current workflows.
Meeting Simulation Program Requirements
Many energy codes include some requirements for the simulation program used to produce the results reported. ASHRAE Standard 90.1 is a common example in the USA that includes a check list of simulation program requirements. All these items are meet by EnergyPlus, and therefore loadmodeling.tool. The follow list is a brief overview, for more information on the validation of the platform please see this help article.
Run 8760 hours per year
At least ten thermal zones
Hourly variations for occupancy, lighting, equipment, set points, etc.
Hourly values of climate data
Perform all design load calculations
Report all standard energy end uses
Proposed and Baseline Workflow
In order to report compliance via energy modeling there are two core steps. First, create the proposed model, and second create the baseline. The energy results from these two models are then compared and to demonstrate compliance is meet.
1. Creating the Proposed
Creating the proposed model is the activity many projects are already doing. This is the model used for sizing HVAC systems, and if part of the project scope, showing the estimating energy consumption. To reach full compliance there will be some final modifications required, such as ensuring unmet hours are within required ranges. On the platform this will be your primary model and will be used as he source model when creating your baseline.
If the simulation requirements include modeling the service hot water, exterior lighting, etc. we recommend exporting the model into OpenStudio and completing the modeling here. OpenStudio is a powerful opensource tool provided by the US DOE which can be used to complete compliance modeling of all types.
2. Creating the Baseline
To create the Baseline model, the first step is to duplicate your proposed model so that we have the starting point to work from. To copy a project proceed to the project page, select the proposed project and click the copy button. See this help article for more information on copying projects.
Next, modify the new baseline model to meet the specific requirements of your compliance path. This can mean many things such as
Modify window to wall ratios
Modify lighting power densities
Modify HVAC zoning
Once the model reflects the requirements for your baseline, run the simulation and use the new results as the basis for your compliance submission! You can use either the Annual Energy Report provided, or the standard EnergyPlus report file which is always included in the Building Analysis Model Export.
Energy Cost Budget Method
The Energy Cost Budget or ECB Method is an alternative to prescriptive compliance pathway that requires less effort than the Appendix G approach. The simulation program requirements are similar, with a key difference being the minimum hours per year of 1400.
The method requires comparing some minimum efficiency inputs against the proposed design. Refer to chapter 11 of ASHRAE Standard 90.1 for the complete definition. Result reports and project input reports can be used to meet the documentation requirements of ECB.
The cove.tool engineering team has plans to automate creation of these baseline models, making delivery of compliance energy models even easier! Check back often to see all the updates or subscribe to our newsletter!