Building Energy Modeling (BEM)
This page is unfinished. Feel free to help the project by sharing your knowledge about this subject.
Introduction
There is currently 2 BIM format related to energy modeling : gbXML and IFC (using IfcRelSpaceBoundary2ndLevel) Most energy analysis software reads gbXML. Some read IFC. Generating geometry for gbXML and IfcRelSpaceBoundary is quite similar. Information contained in both format is different.
[Add a gbXML vs IFC features comparison]
Energy modeling workflow (/!\Work in progress/!\)
Modeling the building
Building need to be modeled with all data relevant to energy analysis :
- Building geometry : Walls, Slabs, Doors, Windows, Spaces etc…
- Energy data : Thermal transmittance, wall layers, thermal conductivity, solar transmittance, light transmittance etc…
Overmodelled building often lead to error and/or uselessly complex computation. A energy model should be simple and contain only energy relevant information.
Energy specific geometry
An algorithm need to generate energy specific space boundaries
Export to common energy exchange formats
Software need provide an Ifc or gbXML.
Adaptation to local standards
Both IFC and gbXML are not directly usable for local standards as each country have it's own specification. [Add an exemple]