A picture is worth a 1000 words. Sankey Diagrams are attention grabbing flowcharts that help in quick visualisation of the distribution and losses of material and energy in a process. The width of the lines used in drawing the flowchart is proportional to the quantum of material or energy. The irish engineer Matthew Henry Phineas Riall Sankey (1853 - 1921) was the first to use the volume proportional representation of energy flows to analyse the efficiency of steam engines.
The Sankey diagram is very convenient tool to represent energy flow in any equipment or system such as boilers, fired heaters, furnaces after carrying out energy balance calculation. This diagram represents visually various outputs and losses so that energy managers can focus on finding improvements in a prioritised manner. A Sankey Diagram is also a powerful tool to sell concepts and ideas within a group and to the top management. There are many software available in the market to help construct a Sankey Diagram.