IES is offering a free software that is fully compatible with Autodesk Revit! The release date is June, but you can register here and be notified when it's ready.
VE-Ware provides instant feedback on a buildings’ energy consumption and carbon dioxide emissions based on real geometry, and using international data on climatic conditions and the typical characteristics of different buildings, room and system types. It is ideal for use at early stages as it facilitates iterative design, allowing the comparison of different design, layout and system options.
It will also assess how the building is performing against the Architecture 2030 Challenge benchmark.