A software with a Sankey diagram feature that I hadn’t noticed before, and only now have added to the list of Sankey Software tools is CASAnova (new house). From what I understand this freeware tool was the result of a research project at a German university that ran from 2000 to 2002.
The program ‘CASAnova – An Educational Software for Energy and Heating Demand, Solar Heat Gains and Overheating Risk in Buildings’ is designed for an easy-to-use handling in order to get an intuitive understanding of the relations between building geometry, orientation, thermal insulation, glazing, solar heat gains, heat energy demand, heating and primary energy as well as overheating in summer.
CASAnova can be used to enter numerous parameters for a building, such as geometry, window and wall areas and types, insulation, heating system, and climate data etc. The tool will eventually produce a generic Sankey diagram of energy flows as the one above. I have just installed it and played around a little bit only to get an impression. CASAnova is available in German and English. Recommended.