The Energy Simulation Failed

[ChrisBriley-ID]

I'm having trouble running an energy simulation.  I keep getting this error and I'm afraid I have no way to figure out the cause.  I'm not knowledgeable enough to figure out the cause on my own, and i'm afraid I can't find the answers in any tutorials.

Any help would be appreciated.  I'm also happy to share the Revit file if it helps in the diagnosis.

thanks.

Chris

[Mohammad_Asl]

Hi Chris,

I can help you with this issue. In order to get more information on the error, can you go to Green Building Studio website and hover your mousse on the cross red sign to see the more detailed error. If you can send me the screen shot of that error, I can help you to solve it. I can also have a look on your Revit file as well.You can send your file to (mohammad.asl@autodesk.com)

Here to help if additional clarification is needed, otherwise please accept as a solution so that others can benefit from this information.

[Mohammad_Asl · Accepted solution]

Hi, 

Here is the error message that comes up in GBS:

This error is generated due to a limitation on the DOE2 energy analysis engine used by Revit/Green Building Studio. What it actually relates to is an instability in the simulation i.e. it is not just specific to walls but any building elements that are too light (or too heavy) subjected to rapidly changing external environmental conditions and/or internal gains (like a large heat gain coming on quickly) causes the simulation to becomes unstable. All dynamic thermal simulation engines are prone to this but for different configurations.

I checked your model and object with aim0081 is the roof with “Basic Roof: Viridescent 2x6” type with a few very thin layers of construction which DOE2 cannot handle. If you choose a different roof construction (I would start with  generic roof with one layer construction) the simulation successfully goes through.

Please refer to this Video for more details on how an accurate Energy Analytical Model can be created in Revit. 

Here to help if additional clarification is needed, otherwise please accept as a solution so that others can benefit from this information.

[Anonymous]

Hi I am encountering the same problem. How do u actually identify which element is the problematic one?

[Anonymous]

Hi

I'm also facing the same problem to identify the error. Can anyone help me on this? Thanks.

[ChrisBriley-ID]

I gave up on Revit as an energy modeling tool long ago.  It would be fantastic if it could be used seemlessly and easily as our projects progress, to deliver live data as we make modifications. But the steps involved, the logging into 360 and GBS and those interfaces, the constant errors, the lack of tutorials and support, the lack of control of granular parts of the building assemblies and glazing, and the lack of confidence I have in any data it generates makes it so it does NOT fit comfortably in our work flow. We're currently using WUFI for our energy models. The effort to results ratio is far more agreeable than Revit and GBS.

It's a real shame because all of our modeling and drawings are native to Revit and all of the data is right there and available for the software to deliver an incredibly accurate model, but this does not seem to be a focus or priority for Autodesk. Hopefully with the next version, Autodesk will make a strong effort to make Energy modeling in Revit an easy and accurate thing for us. But I tend to doubt they will.

Good luck.