by Brianna Crandall — March 21, 2011—The U.S. Department of Energy’s (DOE) National Renewable Energy Laboratory (NREL) has added more features to its suite of energy modeling tools. DOE’s EnergyPlus is a powerful simulation engine that provides comprehensive building energy modeling. NREL is working to add tools to EnergyPlus, via its OpenStudio Application Suite, to improve overall functionality and make EnergyPlus easier to use.
“The easiest way to describe OpenStudio is a wrapper on top of EnergyPlus,” said NREL Senior Engineer Nicholas Long. “OpenStudio handles the building geometry, building envelope, plug loads, people and daylighting, along with many other inputs. It adds all of that data into one big massive engine and spits out results. Industry professionals will find that OpenStudio will help them quickly and easily analyze the energy use in their buildings.”
The first version of OpenStudio was released in 2008 and is a plug-in that leverages Google SketchUp, a user-friendly 3-D drawing program. “OpenStudio was originally developed so people could view and edit geometry for EnergyPlus models,” NREL OpenStudio Developer David Goldwasser said. “We’ve now expanded it to be able to view and edit a lot of the other attributes of EnergyPlus building models, for example putting in loads like lights, equipment and simple HVAC systems.”
The new suite of OpenStudio tools, some of which the NREL team has developed and some of which they are leveraging from Google and its massive investment in SketchUp, includes the SketchUp plug-in plus:
- ModelEditor, which provides users with a simpler way to edit the building model. It includes a way to access components that don’t have a physical representation in a building, like a mechanical system.
- ResultsViewer, a way to review EnergyPlus simulation data in a graphical format. It allows users to look at the data, draw conclusions and compare results.
- RunManager, an application to run simultaneous simulations. This powerful tool can be used to run simulations on a desktop, computer cluster or even a super computer. Designers can compare results between differing models to see where the best energy savings can be achieved.
The OpenStudio plug-in also heavily leverages a feature in SketchUp called Match Photo, which uses photographs of a building to create a 3D model, almost effortlessly. Once the 3D model is finished, users can use the plug-in to trace over windows and doors for EnergyPlus’ use in running an energy model.
In addition to collaborating with Google, the NREL development team collaborates with OpenStudio users through the open source code. Users can submit their own codes for a new feature, or simply use an API [application programming interface] and “plug-in” to the software and write applications without changing the NREL code.
