Recent copy of CADLine magazine had an article on Greenspace Research. I didn't pass much heed to it until it was mentioned at a seminar yesterday.
http://www.greenspaceresearch.com/
GreenBuildingStudio and gbXML are powerful tools for getting to grips with building energy analysis at the earliest stages of design, when decisions having the greatest impact on subsequent energy use are made. Greenspace Research will support UK architects and engineers in their use of GreenBuildingStudio.

If you're a Revit, Architectural Desktop or ArchiCAD user, free energy analysis of your design is just a mouse-click away.
Some links within the site not working.

Apparently due to go into Beta testing next month, available end of year.