Sankey charts, often referred to as Sankeys, were co-invented by a British engineer, William Playfair, and an Austrian economist, Karl Edward Rosenbach, in the late 19th century. Since then, they’ve become a powerful tool in various fields for visualizing flow networks and their associated dynamics. Initially used in industrial applications like energy efficiency analysis and cost accounting, Sankey charts have transcended to multiple other industries such as environmental studies, operations management, and even data science. Their ability to show the quantification of flows among different variables in a streamlined format is what differentiates them from more traditional graphical representations like pie charts or bar graphs.
### Process Mapping: Simplifying Complexity with Sankeys
The quintessential use of Sankey diagrams in process mapping involves illustrating complex workflows in a more comprehensible manner. By representing the flow of materials, energy, money, or people as vertical riverbed-like stream lines between the flow sources and sinks, Sankey charts give users the ability to:
– **Identify bottlenecks**: Quickly pinpoint areas where the process flow is interrupted or limited.
– **View the magnitude of flow**: The width of stream lines in Sankey diagrams corresponds to the amount of flow through an element, making it easy to compare the significance of flows at a glance.
– **Analyze efficiency**: Determine where resources are being wasted in a process.
Within process mapping, Sankey charts could be used, for example:
– To map the flow of inventory through a supply chain and identify inefficiencies in production.
– To track the flow of financial data in a company’s accounting department or project the flow of water throughout an irrigation system.
### Flow Analysis: A Closer Look at Complex Processes
In addition to process mapping, Sankey charts excel at demonstrating the dynamics of flow through a system across different dimensions. In flow analysis applications, some common uses include:
– **Energy Loss Studies**: Visualizing heat losses through walls and roofs in buildings to enhance energy conservation efforts and lead to more efficient design improvements.
– **Resource Utilization**: Showing how raw materials are transformed into finished goods while illustrating the waste streams in a manufacturing process.
– **Effluent Flow**: Monitoring the flow of waste and effluent from industrial installations to assess environmental impact and compliance with environmental regulations.
#### Sankey Charts and Data Science
The modern data scientist can harness the computational power of Sankey diagrams through software packages such as Python, R, and Gephi. These charts can help in:
– **Network Analysis**: Understanding and visualizing the connectivity and dynamics of networks in various domains, from computer networks to social interactions.
– **Big Data Processing**: Simplifying flow analysis in complex multi-dimensional datasets to reveal insights that would otherwise be hidden or extremely difficult to interpret.
### Overcoming Limitations
Despite the powerful insights Sankey charts can provide, they are not devoid of limitations. Visualizing highly complex systems may require breaking down the system into segments, which can result in diagrams that are too fragmented. Also, while Sankeys can represent the magnitude of flow, they often do not provide as much detail as other types of flow diagrams and are somewhat less suitable for representing high-precision data.
Yet, their strengths often outweigh these limitations, making them an effective choice for visualizing process networks. From streamlining workflow improvements to illuminating underlying inefficiencies, Sankey diagrams continue to be a versatile and effective resource in the toolkits of professionals across diverse disciplines.
In summary, Sankey charts are more than mere graphical depictions—they are gateways to understanding the hidden flows that shape our world, whether tracking the flow of energy or showcasing the progression of information in complex systems. Their ability to simplify complex process and flow analysis cannot be overstated, making them a valuable asset to anyone serious about unlocking the productivity and efficiency of everyday operations.
