Why Does Building Performance Simulation Software Suck so Bad?

Back in February, I saw Autodesk CEO Carl Bass give a talk at Cleantech Forum San Francisco.  Full video of the talk is here.

Bass says computers have become so cheap and so powerful that they can be used in exciting new ways in the design process.  An hour of CPU time now costs about $.25.  Dollar for dollar, computers today are ten thousand times more powerful than they were ten years ago.  Design decisions once made by gut feeling or guesstimation can now be made by analyzing sophisticated 3-D models on cheap, ubiquitous desktop computers.  Mistakes can be made in bits (cheap, infinite), rather than in atoms (expensive, wasteful).

Bass' commitment to cleantech was impressive.  He rightly described cleantech as the biggest challenge of a generation.  And he re-announced their Clean Tech Partner program, whereby Autodesk gives away up to $150,000 in software to cleantech startups, with very few strings attached.  Paul Cousens runs the program, and is great to work with.

But I want to address one part of Bass' talk.  He says every building ever built has been a prototype (with a few exceptions like tract housing).  This makes building ripe for energy use analysis (especially since buildings are responsible for something like 60% of energy use).  And yet, he says, what if you ask an architect who's just finished designing a building: How would this building's energy use change if it were rotated by 20 degrees, or if the walls had a higher R-value?  Most architects would admit they should know the answer, but most don't.  Admittedly, these are complex questions, but Bass implies Autodesk software can help find the answers.

The problem is, Autodesk's Sustainable Design tools wouldn't offer much help to the architect in question.

Revit is Autodesk's 3D building design software.  It's powerful and relatively easy to use.  To create a wall, you just click where the wall should go.  But Revit has no built-in abilities to analyze a building's performance.  Though you can select a material for the wall you just drew, the software doesn't know the thermal properties of that material.  You can place HVAC equipment, but the software doesn't know how efficient it is.

Thus, after a designer has painstakingly built a buidling model in Revit, she can't say anything about its energy performance.  It's just a bunch of lines and boxes on a screen.  More specifically, she can't answer Bass' question: How would this building's energy use change if it were rotated by 20 degrees?

To even begin to run an analysis, the designer would have to export to .gbxml, a green building-specific file format.  GBXML files contain some basic geometry data about the building model, but nothing about the materials the designer specified.  So using any analysis tool means re-entering information about every material used in the building: exterior walls, slab floors, foundations, windows, doors.

Autodesk acquired Ecotect in June 2008, but the software hasn't changed much since then.  It's an incredible piece of software, but its user interface is seriously lacking--a far cry from Revit and Inventor.  It's too powerful for most users, and it tries to do too many things.  Running an analysis means making too many minute decisions, like how many people will be in the building during which hours of the day.  And as far as I know, Ecotect has no way to include HVAC systems in its analysis, which limits it utility significantly.

Acquired around the same time, Green Building Studio is also interesting.  Setting the location of the building to be analyzed is done with a Google Maps interface.  GBS even uses the web to find average energy prices for the building's address--very Web 2.0.  But specifying materials and HVAC equipment in GBS is a pain; there's a set list of materials to choose from, so you're out of luck if you're planning to use a cutting-edge product like SeriousWindows.  Why not let us specify the U-value of our windows?  The pop-up menu listing the HVAC options is far too long, and doesn't include options like multiple separate HVAC systems.

This is especially frustrating because other Autodesk software can perform complex analyses with much less effort.  In Autodesk Inventor, simulation and analysis are baked right in--no need to export or switch programs.  I can build a model of a simple part, add some forces and restraints, and *poof*, I can see how much that part will deflect under load.  Need an animation of the part deflecting in slow-mo?  Two clicks and it's done.  Oh, and how about making Inventor optimize the part's thickness to ensure it's only as thick as it needs to be?  Yea, we've got that.  No engineering degree required.

I initially looked into this issue 6 months ago.  Unfortunately, little has changed since then.  I was hoping Revit 2011 would inherit the analysis capabilities of Ecotect, making building performance analysis an integral feature.  But it looks like that only happened for one feature, the sun path simulation tool.  Maybe Ecotect 2011 would finally be a mature, usable product?  Nope, sounds like Ecotect 2011 will be practically identical to 2010.  And Green Building Studio?  Just as klunky as when I used it last year.

What gives, Carl?  Why isn't this a priority, given the scope of the problem (buildings are responsible for over 50% of energy consumption) and your company's core competency in designing (generally) intuitive, powerful software?

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