Building Performance Knowledge Community

Looking up at Buildings and Sky

Quick Links

Who we are

The goal of the Building Performance Knowledge Community (BPKC) is to promote architects as leaders in the application of technical design for building performance; in the use of high-performance design criteria, codes, and standards; and in programming, designing and managing building performance. To advance, disseminate, and advocate—to the architecture profession, AIA members, building owners, the construction industry, the academy, and the public—design practices that create buildings that are healthy, energy efficient, and durable.

Expand all | Collapse all

Energy Modeling Software

  • 1.  Energy Modeling Software

    Posted 04-09-2018 15:41
    Does anyone have a recommendation for software that is easy to use and relatively inexpensive for doing energy performance analysis at the schematic design (or before) phase?  We are looking for a tool that gives good quantitative comparisons for things like massing, orientation, fenestration, and so forth.

    Kim Shinn
    Principal/Sr Sustainability Consultant
    TLC Engineering for Architecture
    Brentwood TN

  • 2.  RE: Energy Modeling Software

    Posted 04-10-2018 17:37


    The quickest and easiest to use for small to medium-sized buildings is Murray Milne's HEED and SBEED as well as Climate Consultant  and Opaque, available for free at <>.  HEED and SBEED are tools that gives good quantitative comparisons for things like massing, orientation, fenestration, and so forth.

    Hope that helps,

    Bruce Haglund Assoc. AIA
    Professor of Architecture
    University of Idaho, College of Art & Architecture
    Moscow ID

  • 3.  RE: Energy Modeling Software

    Posted 04-10-2018 18:02
    I think you want something Good, Easy and Cheap but probably there's nothing in the market that can cover all three.

    If it is Good and Easy, I'd go with Sefaira. It's very intuitive, the modeler is SketchUp and you can run parametric (multi-iteration) runs, either comparing to a baseline or cumulatively with other runs. It shows the EUI of every iteration as a reference and it tells you how far it is from ASHRAE 90.1 Appendix G or the 2030 Challenge. Another good thing is that it has Daylighting and Glare incorporated into it as well. It's not cheap of free, it has an annual subscription of $3000 per seat I think.

    If it is Good and Cheap, I'd go with EQuest, which is free. It's very reliable but hard to model and to  navigate. It gives you EUI but you have to know where to find it and it can do parametric (multi-iteration) runs as well.

    There's also Ladybug/Honeybee or DIVA/ArchSim (which plug into Rhino via Grasshopper), but they're more oriented towards Load Calculations and not a full Energy Model with HVAC systems and all. They give you results in kWh/yr/m2 and both can also run parametric (multi-iteration) runs. Both do have Daylighting and Glare and they are very reliable (DIVA is a little more established than L/H).

    I'd stay away from Autodesk's products like the plague. They charge you per simulation run and their simulation engines haven't been validated because they don't want to show their algorithms to third parties.

    Hope this helps.

    Alfonso E Hernandez AIA
    Founder + Principal
    MEDiAM Design Collaborative Architects
    Houston TX

  • 4.  RE: Energy Modeling Software

    Posted 04-10-2018 21:03

    Hi Kim – we really like using SketchUp paired with the Sefaira Architecture plug-in analysis tools for early design studies like you are describing. There is a Sefaira plug-in for Revit, if you're already doing your early modeling/design in Revit. The Sefaira tools allows comparisons between multiple scenarios and kicks out fairly routine benchmarks like EUI, and heating/cooling therms. Also has some great daylighting analysis tools useful for early design when there's some flexibility with orientation and fenestration.


    Sefaira Systems is an alternative offering that is more oriented to mechanical engineers as opposed to architects/building designers.


    Todd A Jespersen AIA, LEED AP BD+C

    Principal Architect

    Kruger Bensen Ziemer Architects, Inc.

    30 W Arrellaga St

    Santa Barbara, CA  93101

    (805) 963-1726 x3358



  • 5.  RE: Energy Modeling Software

    Posted 04-12-2018 09:41
    Kim -

    I would concur with the other recommendations regarding the use of Sefaira for all the same reasons. It is probably the best option out there for early and fairly detailed analysis. I would recommend Sefaira Systems, simply because you get all of the architectural features plus greater depth of system types and variable analysis.

    Jason Hainline AIA
    Design Associate
    Dake Wells Architecture
    Springfield MO

  • 6.  RE: Energy Modeling Software

    Posted 04-11-2018 01:09

    Kim −

    The answer really depends on what you and your team need from the software.  I can add little to the list of tools already mentioned but will provide a few more details.  Based on your need for Easy to use, inexpensive, and able to do "…energy performance analysis at the schematic design (or before) phase" narrows your choices down quite a bit (now that Ecotect is gone), and that would be either a Rhino/grasshopper workflow with either Honybee and Ladybug, or DIVA and Archsim, or Openstudio with Sketchup.

    I would add BeOpt ( to Professor Haglund's list of reliable tools that should be useful for any designer of small projects.  BeOpt adds a parametric and optimization component to the design process.  These tools are readily available, easy to learn and to use.  However, BeOpt and HEED quickly become limited when dealing with increasingly complex designs, therefore limiting their use to residential and small scale projects.

    Before eQUEST, I would direct you to OpenStudio (OS) as a valuable tool with much more capability for building performance analysis, but with a learning curve (  Openstudio allows the user to take a project from conceptual massing through to detailed analysis for code compliance and Green Building credits.  The software is free and geometry can be created in Sketchup.  The software is able to handle complex and larger projects than HEED and BeOpt as well as providing detail and flexibility relevant to the level of analysis needed.  The energy simulation engine behind OS is EnergyPlus, which will give a great deal of detail and flexibility for future energy studies if required.

    eQUEST is indeed a powerful, robust, and free ( tool as already described.  However, it does have a steep learning curve and is not as flexible in exploring site or context in the early design phase.

    With that stated, the two strongest tool sets for experimental, conceptual, and schematic design (even predesign) would be the Honybee and Ladybug (HB+LB) (, and DIVA and Archsim (, and for Rhino/Grashopper both of which provide more options for early design exploration than and other standalone tools currently available.  The HB+LB plugins are also available for Revit/Dynamo work flows.

    There is considerable overlap between these two tool sets however, HB+LB provide more tools for climate, site, and urban microclimate analysis.  As with OS, EnergyPlus is used by both HB+LB and Archsim as the simulation engine allowing for more detailed analysis in other programs or to output a usable idf file for your energy consultants.  For solar and lighting simulations both HB+LB and DIVA employ Radiance as the simulation engine. 

    Notable drawbacks include: a copy of Rhino (or Revit) is needed in order to run these tools; the learning curve for either tool can be steep if the user is unfamiliar with the visual programing process used in Grasshopper or Dynamo; DIVA and Archsim has an added cost to purchase; the depth and detail of results can be limited to the users experience.

    The benefits to these tools are that they are part of a greater network of plugins for the Rhino/Grasshopper software allowing for great flexibility in the exploration of form and context; Rhino costs less for a perpetual license than a single seat for Revit or Sefaira for a year; there is a very good chance recent architecture graduates have experience with a Rhino/Grasshopper workflow, potentially saving time and cost on the learning curve; with more experience, more detailed results can be extracted from the tools; and if the limits of the tools are reached, the E+ idf files these tools produce can be easily imported into a devoted energy simulation tool (i.e. Simergy,

    My personal workflow includes DIVA/Archsim and/or HB+LB until the design is nailed down, then export the energy file (idf) to either Openstudio or, if I need fine detail and advanced optimization of building elements, to EnergyPlus where I use a combination of a text editor and (gasp!) the native EnergyPlus idf editor.

    For a more comprehensive list of energy and lighting simulation tools, please refer to the BEST Directory hosted by IBPSA at  There you will find all these programs and many more with links.

    Hope this helps.

    James Erickson
    Architecture :⇔ Design ∩ Research ∩ Environment

  • 7.  RE: Energy Modeling Software

    Posted 04-16-2018 23:46
    Vectorworks has a built-in energy modeling called Energos.   You can see a demonstration on Utube.  Google VectorworksEnergos


    Tim Mead, AIA, Architect

  • 8.  RE: Energy Modeling Software

    This message was posted by a user wishing to remain anonymous
    Posted 04-25-2018 18:44
    This post was removed

  • 9.  RE: Energy Modeling Software

    This message was posted by a user wishing to remain anonymous
    Posted 04-27-2018 18:53
    This post was removed

  • 10.  RE: Energy Modeling Software

    Posted 04-30-2018 10:52
    Edited by Kjell Anderson 04-30-2018 10:52

    Kim and all,

    We (LMN Architects, 150-person firm) have experimented with a variety of energy simulation software. A non-exhaustive list and our preferences are below. In general, modeling daylighting and solar studies are easier for architects to get into and can be done with some training. Analyzing single zone models like COMFEN can be a good next step, as is load analysis (how much heating and cooling is required, without designing a mechanical system). The most difficult is whole building energy modeling – eQuest, EnergyPlus, Trace Trane, etc. because someone needs to select and design a mechanical system and architects are not trained to do this. To the extent it’s easy to get results without any training, the results are not very meaningful. To the extent it takes training, it requires some investment. Training needs to include what buttons to click within software, but also what the underlying energy flows are that are being modeled. 


    There are 3 pieces to any energy modeling software, and each software recommendation below describes which pieces are bundled together:

    An engine. This contains the math that simulates the physical world within the digital.

    3d modeler. This is how you input geometry.

    Graphic User Interface (GUI). This is where you click buttons to input various parameters and eventually run a simulation. Often the GUI also provides graphic outputs that you interpret to help make design decisions.


    We like:

    Diva for Rhino/Grasshopper is our favorite daylighting software. It is fairly easy to use, with good default inputs and tutorials. It also runs solar analysis. (GUI, uses radiance as daylighting engine, uses Rhino as 3d modeler)

    COMFEN. Easy to use, hard to get a wrong answer from, generally limited to comparing fenestration, orientation, and shading. (GUI, 3d modeler, and uses EnergyPlus for the engine)

    Rhino/Grasshopper/Ladybug/Honeybee + other bugs. We use Rhino and Grasshopper for early explorations already, so adding the bugs means we don’t have to spend much time translating geometry from one program to another. (Rhino is 3d modeler, Grasshopper is GUI, with various engines being used) Ecotect. now no longer available – but had great weather visualization and a variety of daylighting and load calculation abilities. (GUI, 3d modeler, and engine)

    Climate Consultant. Limited to analyzing climate with Atari-quality graphics, but very useful for quick climate analysis. (no energy modeling)


    Other software: Sefaira. I have had limited interactions with Sefaira. I think most architects would learn a great deal by playing with Sefaira, but I am skeptical of any results that are intended to change the design direction of a building are easy to get without any training in building energy use modeling. Before making a design change based on modeling results I’d run any results past someone with more training in energy use. (To the extent results are not intended to change the design of a building I’d ask why you are spending time with energy modeling) (Sefaira is a GUI, can use SketchUp (and purportedly Revit) as a 3d modeler, and uses proprietary algorithms or EnergyPlus as an engine)

    Archsim could be grouped with the Rhino/Grasshopper group, but it requires more understanding of energy use, so we don’t use it as much as we’d like. Archsim is bundled with Diva. (Archsim allows use of EnergyPlus as an engine within the Grasshopper environment)

    OpenStudio. I’d love to talk to anyone that uses this regularly. It’s been in development for a long time. It’s a GUI that uses EnergyPlus and other engines. I am not sure which 3d modelers it works with.

    Original Message------

    Does anyone have a recommendation for software that is easy to use and relatively inexpensive for doing energy performance analysis at the schematic design (or before) phase?  We are looking for a tool that gives good quantitative comparisons for things like massing, orientation, fenestration, and so forth.

    Kim Shinn
    Principal/Sr Sustainability Consultant
    TLC Engineering for Architecture
    Brentwood TN

  • 11.  RE: Energy Modeling Software

    Posted 05-01-2018 18:06
    I've settled on BEOpt. It is single zone with a primitive modeler. One drawback is you can't model shed roofs. However, BEOpt's parametric feature lets you run dozens of simulations in less than an hour. So I will settle on a building massing and then take a look at maybe four fenestration options, four insulation options, a couple lighting options and a couple occupancy options. That's like 4x4x2x2 different scenarios. BEOpt will crunch Energy Plus simulations for them all (it has a search tree algorithm, too). You get to look at which combination of insulation, fenestration and lighting work best together, for instance. One lesson I've learned is that on small projects in Climate Zone 6A, anything more than 5% fenestration on the north side and 10% fenestration on the west and east sides is an energy loser, even with triple glazing. These insights have been valuable. Another is that 30% better R value in the lid than in walls is just about the sweet spot.
    So, I recommend BEOpt.

    Mike Sealander, AIA
    Maine Licensed Architect
    cell 207.266.5822

  • 12.  RE: Energy Modeling Software

    This message was posted by a user wishing to remain anonymous
    Posted 05-02-2018 17:32
    This post was removed

  • 13.  RE: Energy Modeling Software

    This message was posted by a user wishing to remain anonymous
    Posted 05-02-2018 19:23
    This post was removed