Who is this for: Users of Autodesk Green Building Studio through the web interface or through Autodesk Revit and Vasari.
Takeaway: The February 14, 2014 release of Green Building Studio (GBS) web service now uses the newest 64-bit version of DOE-2.2-48r, which includes Autodesk code enhancements. Autodesk and Intel teamed with JJHirsch and Associates to embark on making DOE-2.2 and eQuest more BIM friendly. These enhancements included:
- Speed enhancements
- Better shading polygon support
- Modifications of window convective calculations per NREL documentation
- Addition of an ASHRAE enhanced infiltration correction
- Increased limits for several objects.
|Baseline (DOE-2.2-44e4) limits||New DOE-2.2 version 48r limits|
|Number of spaces||4096||9999|
|Number of exterior walls||8192||64,000|
|Number of windows||8192||64,000|
|Number of interior walls||8192||64,000|
|Number of Underground walls||8192||10,000|
|Number of doors||1024||4096|
|Number of building shades||1024||10,000|
|Number of polygons||32,768||120,000|
The current release of eQuest and DOE-2.2 includes these enhancements and is available at DOE2.com.
The 64-bit version of DOE 2.2 allows us to utilize more of our cloud-based server’s hardware and memory, which results in an increase in the simulation speed. We expect approximately 30% typical reductions in simulation time with this new release.
Revisions to the DOE-2.2 software result in some changes to the GBS energy analysis results (thereby affecting Revit and Vasari energy analysis results). Simulations from 464 test cases covering 4 conceptual models, 16 climate locations, and 29 different building types result in changes in annual electricity consumption between -2.1% to 3.0%, with a median change of 0.4% and an average change of 0.4%. The fuel usage differences range from -7.6% to 6.9%, with a median of -1.0% and an average of -1.2%. These change are discussed in detail in this blog: Autodesk Green Building Studio Adopts the newest DOE-2.2 version (48r in 64-bit) for our February 14, 2014 Release.
Call to Action: We would like to invite all users using GBS through the web client, Revit or Vasari to try their models with the new updated DOE 2.2 engine. Please tell us if you see a change in performance (faster or slower) and any significant changes in the analysis results. Also please try out Revit models that have not been able to run in the past because they fail due to the energy model exceeding any of the model element count limits noted above. Please tell us if the models are still failing. You can reach us at the Autodesk Green Building Studio Community Forum.
Note: Autodesk Green Building Studio (GBS) uses the DOE-2.2 simulation engine for calculating the hourly, whole building energy usage of your project. The DOE-2.2 software was developed by James J. Hirsch & Associates (JJH) in collaboration with Lawrence Berkeley National Laboratory (LBNL) . DOE-2.2 has been validated by Lawrence Berkeley National Laboratory and the Los Alamos National Laboratory.