At the CanBIM Regional Session in Vancouver, Mark Cichy, Associate, Director of Computational Design and Research, at DIALOG, gave a fascinating talk about automating the process of designing sustainable buildings.  Specifically the talk focussed on applying computational design based on BIM and building energy modeling to optimizing building energy performance in the context of sustainable baseline standards such as LEED, AIA 2030, Living Building, and others.  This is important for DIALOG which has just committed to AIA 2030.

The primary motivation for energy performance modeling is currently aggressive building codes that push energy efficiency, for example, customer driven certification such as LEED and other “green” certification, and financial incentives from local governments and power utilities to reduce energy consumption, peak load or both. The EU, US and Japanese governments have already mandated net zero energy, near zero energy and zero emissions for public and other buildings starting as early as 2018.

Computational energy modeling is about optimizing energy usage over the entire lifecycle of the building for multiple objectives.  Currently energy performance modeling typically follows a fairly lengthy process starting with a BIM model of a design.

1. Use Revit to create a BIM model of the building.  The model can be either conceptual or detailed, but there are specific requirements it must satisfy to be useful for energy performance modeling. 
2. Create custom schedules in Revit to provide an information framework for the data that is required as input for the energy performance analysis and for storing the results of the analysis.
3. Generate a gbXML model from Revit.
4. Import the gbXML model into an energy performance modeling software such as IES.
5. Clean-up the model and add external features such as nearby buildings.
6. Run the energy performance analysis.

Mark discussed automating this process using generative design based on parameterized BIM models to optimize energy performance in the context of LEED or AIA 2030 or another sustainability standard.  There are a number of BIM algorithmic design and energy performance tools that can be used to help do this.  Mark mentioned Revit, Dynamo, Grasshopper, Ladybug, and IES. Dynamo extends BIM modeling to include algorithmic design. Grasshopper is an algorithmic design application for Rhino.  Ladybug is a free and open source environmental plugin for Grasshopper to help designers create an environmentally-conscious architectural design.  IES is the industry standard tool for detailed energy performance modeling for compliance purposes.  It is a standalone application that takes input from 3D design tools and assesses the design from the perspective of energy performance.

One of the key challenges that is required to enable automating the sustainable building design process is integrating IES with Revit so that every change in Revit is modeled at the same time in IES.  This requires a tight integration of IES into Revit, something that cannot currently be done with IES, but Mark is optimistic that this will be possible in the future.  The other part is generative design based on a parametric BIM model. 

Mark gave a real world example of optimizing a building with respect to different facade designs, lighting performance, and heating performance.  Pretty amazing – this represents significant progress toward integrating generative design and energy performance modeling that will make it much easier to design sustainable buildings compliant with a standard such as LEED and AIA 2030.