LEED Energy Usage - Simulation Programs

So my company has an on-going renovation project in which we will be submitting specific drawings for LEED approval.

In addition we are required by the minimum standards to produce a full building energy usage simulation using one of a few specific simulation programs... I am wondering if anyone has heard of these or what the best one might be. We preferably want something that we can import data from Autocad with.

ANSI/ASHRAE/IESNA Standard 90.1-2007 states under item G2.2..

The simulation program shall be computer-based program for the analysis of energy consumption in buildings (a program such as, but not limited to, DOE-2, BLAST or EnergyPlus). The simulation program shall include calculation methodologies for the building components being modeled. For components that cannot be modeled by the simulation program, the exception calculation methods required in Section G2.5 may be used.

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Do any of you have information on these three programs or perhaps have a recommendation as to what might work best?

I've searched the boards on this but have come up dry... Any help is appreciated. Thanks!

-ChriS

I would recommend looking into eQuest, it is the DOE-2 simulator with a graphical interface. We outsource our energy models and I believe this is what they use.

Thanks Mike!

At first I thought there would be a cost involved but I am currently downloading and installing "DOE-2" and "Energy Plus" which are free and currently approved for LEED per the ANSI/ASHRAE documentation.

I was wondering why they weren't on Amazon!

I'm gonna experiment with the software to see if I can get the information we require for the project rather than outsourcing to someone else.

We may have future projects requiring LEED. Also, I am a one-man show for the company and it will be good to learn the software and have the experience along with it. I will post back here once I've messed around with the software a bit.

-ChriS

SO I've been messing with eQUEST "Energy Simulation Tool 3.65 and trying to figure out a way to import the building profile from Autocad directly into the software - no luck yet and don't know if it's possible. I haven't delved that far into it yet.

The modeling software calculates energy usage by asking a ton of questions that you answer and write numbers in for. But if you type in the building area to be 10,000 Square Feet, for example, it will draw a square structure with that area...

I'm working on how to be more specific about building characterics or if it is even possible. We'll see how it goes.

-ChriS

I know from a conference I attended a few months back that Autodesk does have a program that can calculate solar energy and building massaging etc. From the presentation it looked quite good.

Thanks Organic. I think that might be more if you have a working 3D model of the building though. For example, Energy Plus uses data that you can import from "Sketchup" 3d models. You can import Revit or Autocad 3d models into Opensketch, clarify what is a window, door, zone, etc.. Then export that to Energy Plus modeling software with a Sketchup add-on.

There are likely similar energy modeling add-ons for Revit I would imagine.

The problem is I only have 2d Floor plans. Because it would have been too time-consuming to create a 3d model of a large building from scratch mid-project, the solution for us was to use "eQuest" energy modeling software approved for use in Appendix G of the LEED documentation.

The software allows you to insert a 2D autocad floor plan similar to an XREF. You then scale the floor plan to the proper scale (as one large object) and trace out your zones.

Most of the other information is input manually. (R-ratings, airflow CFM's, etc..).

-ChriS

I'm continuing to work on the energy modeling and thought I would chronicle my efforts here as I go.

we went with eQuest which is the DOE-2 energy modeling software available for free through the department of energy website. DOE-2 is one of the three approved programs approved by ASHRAE 90.1 Appendix G.

Anyone planning on doing energy modeling on their own should definately read appendix G of ASHRAE 90.1.

There is obviously ALOT more that needs to be done for any kind of LEED approval but a sizable chunk of the requirements involves the energy modeling and the data input therein. In some cases alot of the information required by the software may already be available through the LEED point of contact - whomever the LEED-approved authority on the project may be.

I am obviously not at liberty to disclose all the details of this project for various reasons but I hope this thread might come in handy later on for the curious and/or confused.

If you have a working 3d model in REVIT or Autocad you have alot of the work done already because if you go with "Energy Plus" you can import that 3D data into "Sketchup", use the sketcup add-on and specify your zones fairly easily. You can then export the data through the "Sketchup" add-on and use the resulting file with "Energy Plus". But not all buildings have working 3d models and it isn't always in a contract to provide 3d modeling. Also, "Sketchup" is no longer a free program. The only Sketchup program that will allow you to install the necessary add-on is now about $600.

Fortunately, those with Revit are in luck because I believe there is an EnergyPlus add-on for Revit as well. The add-on is required to specify zoning, doors, windows, etc.. some of it may be done automatically (I've only heard about it).

This was my predicament - but the energy modeling is required nonetheless for LEED approval. So we went with "eQuest" instead as an alternate means to the same end.

DWG or DWF files can be imported into the eQuest design development wizard when you start to specify your zones. However, the CAD files are not editable - only scalable as one large object. After scaling the CAD contents to full scale you then trace your zones and name each. In some cases the LEED-certified individual on the project may already have all of the zones and sizes listed which makes things easier.

the design development wizard spits out a file after that is done. That file is then used to specify more specific energy and building usage data.

-ChriS