I began experimenting with the Energy Plus plugin for Google SketchUp. The concept of the tool is to use SketchUp to render a building model and launch a EPlus simulation from it. It is an excellent tool from the geometric aspect as you just have to click and drag shapes to make the structure. The problem is that the simulations don't work!!! Output CSV (Comma Separated Value) files don't come out. Why? It might be a problem of passing parameters or some issues in variable naming consistency. I guess I have to read the Input Output Reference of EPlus to find out. It looks like I'll be using the plugin to render the geometric aspect but I'll use the EPlus IDF (Input Data File) editor to work on the thermal and run parameter. As soon as I figure this out, I'll be saying something about it here. 'Til then....

I just finished doing the tutorial exercises for Energy Plus.  It is an interesting application because you can simulate the cooling and heating performance of a building.  You start out by creating partitions of the building you want to analyze. The software has values on construction materials taken from ASHRAE databases.

Thermal zones of model

The next step is to render sub elements like windows and doors.  As soon as this done,  energy plus can render it as a .dxf file.  

Rendering windows and doors

 You can then simulate building performance based on weather/climate data taken from WMO.  You can also add HVAC, lighting or occupancy components to your model.    After running your model, you can get a good estimate of your energy performance.  The output would be something like this:

Site and Source Energy

	Total Energy (GJ)	Energy Per Total Building Area (MJ/m2)	Energy Per Conditioned Building Area (MJ/m2)
Total Site Energy	233.55	503.77	503.77
Net Site Energy	233.55	503.77	503.77
Total Source Energy	655.37	1413.66	1413.66
Net Source Energy	655.37	1413.66	1413.66

Building Area

	Area (m2)
Total Building Area	463.60
Net Conditioned Building Area	463.60

Resized picture of end use output

Energy plus seems to be a great tool in analyzing building performance whether for retrofits or new designs.  I will be exploring more of this tool and its google sketch-up plug-in. I will be making it part of my arsenal of tools in my advocacy for sustainable energy.  Stay tuned...

drawings taken from Energy Plus getting started guide