10 Things to know about Simergy

Simergy is a comprehensive graphical user interface (GUI) for EnergyPlus that has been developed by a public and private partnership effort. We listened to industry and developed comprehensive workflow solutions to take the user all the way through building design and analysis process from the early stage through to detailed design. The workflows facilitate the cycles of analysis that enable exploration of system types in effective ways and enable innovative HVAC system design.

1. What’s Active, What’s Coming and What’s Not There Yet…

Read me files, Release Notes and other Getting Stared materials aren't always the most exciting reading material, but taking a close look at them will assist getting a good start with Simergy. The Simergy team wants the users to be aware of what is active in version 1 and what is coming, so if you haven't read the "Essential Reading", we recommend it, as well as reviewing the Simergy website on a regular basis for new announcements. In particular, read the Survival tips in the Essential Reading and join the support forum.

2. Chunking

If you are not familiar with the concept of "Chunking", now is a good time to learn. As with any tool that is powerful and complex, it is important to "Chunk" what you take on and what you try and remember, so that the content is broken down in more effective pieces and triggers that can assist learning and retaining more things. The following are some recommended "Chunks", which we have titled "Simergy in 3’s":

  • To create and apply new content - 1) Define Library Entries, 2) Create Templates selecting Library Entries, 3) Assign Templates to Models
  • Content hierarchy high to low - 1) Library file, 2) Templates, 3) Library Entries
  • To define a new wall type - 1) Create materials, 2) Create Material Layers by defining depth or thickness, 3) Choose layers to create a Material Layer Set
  • To create an (air-based) HVAC System - 1) Zone HVAC Group, 2) Air Loop, 3) Water Loops
  • Air and Water Loop Checks - 1) Loop Parameters, 2) Loop Level Controls, 3) Validation
  • To Create a Schedule - 1) Define Profiles, 2) Drag and Drop Profiles to Year Workbook, 3) Save Schedule
  • To Set-up Output Variables for a Simulation - 1) Define Output Requests, 2) Create Output Request Set, 3) Select Output Request Set Template

3. Target Audience for Version 1 and Recommendations for ‘Getting Started’

The optimal users for Simergy includes mechanical engineers, energy modelers, energy analysts, technical architects and technical consultants.  This is because Simergy (and the simulation/analysis engines behind it) have a degree of complexity and thus will have a learning curve.  Simergy eases and speeds up the process of using EnergyPlus by removing the need to deal with xyz coordinates at the envelope level and the need to deal with HVAC node names. That said, some knowledge of EnergyPlus is a distinct advantage. The following are five recommendations for getting started with Simergy, which have been provided by the gurus on the Simergy Team:

  • Watch “The Help Tour” video to learn about the different types of resources that are available and review the “How to Use Help Guide”.
  • Review the Workspace Guide: Look over the workspace guide and open Simergy and look at a few of the workspaces while reviewing the document. This will help to get a feel for the User Interface Landscape of Simergy. Other guides available include – How to Use Help, Natural Ventilation, Daylighting Controls, Results Visualization and ASHRAE System 7 Sample File Guide.
  • Watch some or all of the Short Video Tutorials
  • Sample Files are a Good Starting Point: The Sample Projects serve as comprehensive Simergy examples. Once you have downloaded Simergy, a “Sample Projects Folder” will have been loaded with Simergy (typical location - C:\Users\Public\Simergy\Samples\SampleProjects) that contains a number of different sample projects for different building forms and HVAC system types, including ASHRAE 90.1 systems.
  • Get Familiar with HVAC Diagramming and Libraries & Templates: People don’t typically read the manual before jumping in for a test drive, but in this case taking some time to understand the infrastructure of these two powerful feature areas can really help.

4. EnergyPlus is under the Hood

The engine behind Simergy, that simulates energy performance is EnergyPlus.  EnergyPlus supports a wide variety of HVAC system types — both typical and low-energy.  Simergy enables users to model these systems.   The project model in Simergy ― Simulation Domain Model, or SimModel ― is effectively a union of 4 building industry standards: the IFC moidel (BuildingSMART, 2012), the EnergyPlus input data model, gbXML (www.gbxml.org), and the Standards Data Dictionary (SDD)(California Energy Commission). The SimModel was created to support interoperability between various building energy simulation tools, and to enable Simergy to support other simulation engines, such as Radiance and Modelica-based tools. Users familiar with Energy Plus will recognize the properties (parameters) of the object types included in Simergy.

Throughout the help content there are references and links to the EnergyPlus documentation to provide transparency to 'what's going on under the hood', including linking to the EnergyPlus Input Output Reference with the Simergy Help documentation. In addition Online Energy Plus Documentation has recently been made available. Use the Sample Files as a starting point to get familiar with Simergy, as well as the ASHRAE Baseline System 7 Guide that contains information about all of the inputs associated with this sample file.

5. Geometry Workflow Options

Simergy provides users with the option to import geometry from BIM or 2-D CAD, as well as the ability to create geometry directly. Translation of geometry from Building Information Models (BIM) to Building Energy Models (BEM) has always been a challenge, and Simergy presents a developing solution for this, as well as enabling additional workflows including:

  • Workflow #1 - Build your own geometry utilizing the Simergy tools to develop models quickly and easily from the earliest stages.
  • Workflow #2 - Build geometry from imported floor plans (dxf or dwg).
  • Workflow #3 - Industry Foundation Class (IFC) 2.3.2 Model View Definition for BIM to bring building geometry and additional information into Simergy.
  • Workflow #4 - Import geometry using gbXML

6. HVAC Diagramming Approach (Caution: High Degree of Customization Possible)

The HVAC Diagramming approach within Simergy involves visualization at both the loop level and the individual component level. At the highest level, the user can draw or view the Zone HVAC Groups, air, hot water, chilled water, condenser water and mixed water loops associated with the design. In addition, the user can incorporate sensors and controls into the design on a separate layer that allows the user to view them integrated into the loop design or turn them off, so that a more simplified view of the loop is shown. The two dimensional representations are set up to be familiar to design engineers with the intent that they will be more accessible and intuitive to users and serve as a guide to the additional capabilities that Simergy provides. The user has the choice of building an HVAC design from scratch, using the system templates distributed with Simergy or using one of their own custom system templates.

The system templates that ship with Simergy were developed in collaboration with industry engineers and energy modelers to provide a starting point based on industry best practice. In the Diagram workspace, the user can select and drag components and connections to change the layout of a loop to improve comprehensibility, particularly when exporting diagrams for documentation purposes.

7. HVAC Validation Framework

A comprehensive, rule-based, assignment and validation framework was created for implementation in Simergy to support the transformation from the drawing model to the EnergyPlus input file used for the simulation. Some of the rules enforce physical consistency, e.g. don’t connect an air port to a water port , and are applied continuously during the drawing process. Other rules enforce EnergyPlus requirements, e.g. only one set of parallel branches on the supply side of a water loop, and these requirements are applied at the end of the process of creating each loop by clicking on the Validate button in either the Create/Edit or the Diagram workspace. Problems are communicated as either 'warnings', 'severe errors' or 'fatal errors', the aim being to trap as many errors as possible before running EnergyPlus. The user should still review the EnergyPlus error file generated for each run; the Simergy validation rules only traps input errors and cannot trap run-time errors.

8. Reports & Results Visualization

Finding your way effectively through the maze of simulation results can be a daunting task. Sometimes you want to check certain things quickly and other times you need to investigate and interrogate the results in greater detail. Simergy enables both of these through Reports and Results Visualization (ResViz). If you want to check things quickly, selecting on the different Summary Reports within the reports set allows you to review "graphical and tabular" results in new ways. However, if you need to interrogate the results further, the data visualization capabilities within Results Visualization allows you to explore the output variables individually, in groups and across multiple design alternatives. You can use the predefined Results Screens and Results Screen Templates that include up to four pre-defined views of graphed output variables to quickly start the "deep dive" or you can create and customize your own using the different chart types.

9. Libraries & Templates

These are two key core elements of Simergy that drive the ability to generate BEMs. Both are tabs on the main interface ribbon and each includes a significant number of workspaces that enable some of the more powerful features within Simergy. Libraries contain homogeneous sets of information, e.g. fans, whereas Templates contain heterogeneous sets of information, e.g. a specific type of HVAC system. Library files (Source Libraries) contain Templates and different categories of Library. Libraries contain Library Entries, which consist of Properties.

Simergy version 1 ships with one Source Library (containing information from different sources, mainly ASHRAE Standard 90.1. This library can be copied, added to and shared with other users. Different library files, up to four at once, can be selected via Options on the File menu. The library content is classified into Library Categories (different workspaces e.g. chillers, wall constructions) that allow the user to review and create Library Entries. The user can select library entries from previously assembled library entries and/or create new ones by selecting a combination of type and sub-types to generate a set of variables to be populated with values by the user. Selecting Libraries on the Ribbon shows the large number of library types that are available to support the Templates. In addition, there are Libraries workspaces, such as Calendars and Schedules, that provide the ability to create schedules in a user friendly, graphical way.

Templates provides the user the ability to combine different types of information by assembling sets of library entries that are shipped with Simergy and/or custom libraries created by the user . System Templates provide users with pre-defined sets of zone conditions for linking to Zone Groups and pre-defined zone HVAC equipment configurations for linking to air and/or water HVAC loops. The System Template workspaces are set up in a similar fashion to the System Diagram workspaces so that users can build the System Templates in the same way that they build a specific system for a project.

10. Full Sample Files (Simulation Ready)

(Typical location - C:\Users\Public\Simergy\Samples\SampleProjects). The sample files are downloaded with Simergy. See the ASHRAE Baseline System 7 Guide, which can be accessed from the green question mark icon in Simergy. They contain all the elements that that are required in Simergy to run a simulation, including location, site, building geometry, Zone Groups and Zone HVAC Groups, HVAC systems, controls and required component properties. Taking a closer look at these files or, better still, try them out to reduce the learning curve for Simergy.
Bonus: "But it goes to 11"...

11. Feedback

Feedback– We need and welcome your feedback in order to help us enhance Simergy. You are encouraged to log issues, propose enhancements and ask questions by using the support form on the Simergy website. This way the submission can flow directly into a log and be tagged and tracked. Use the Windows Snipping Tool (All Programs | Accessories | Snipping Tool) to capture all or part of the screen to a file or files – this is a very powerful and convenient tool for documenting and reporting issues ; please also be sure to specify the simplest, most direct way to reproduce the problem. For general comments and feedback, send an e-mail to