Sankey charts are a type of flow visualization chart that have been gaining popularity in recent years. This type of chart is particularly useful for visualizing complex systems and data flows, such as energy systems, supply chains, and network traffic. In this article, we will explore the process of creating Sankey charts, the different types of Sankey charts that are available, and some of the specific applications of Sankey charts in various industries.

Creating Sankey charts requires specialized software such as Tableau, PowerBI or R with specific libraries (e.g., sankeyR for R). Here are the basic steps:

Step 1: Prepare Your Data: Gather your data, which should include the starting node, the end node, and the flow volume associated with each node.

Step 2: Arrange Nodes on the Sankey Diagram: This is done using two sets of arrays: one for the source nodes and another for the target nodes. The x-axis usually represents the source nodes, and the y-axis represents the target nodes.

Step 3: Define the Flow: The flow or link strength is the third variable that needs to be defined in a Sankey chart. This could be represented by the width or color intensity of the link between the nodes.

Step 4: Generate the Chart: Input your defined node relationships and flow volumes into the chart software’s Sankey diagram generator. The software may automatically adjust the placement and size of the nodes based on the flow, or you’ll need to adjust manually to improve the chart’s clarity.

Step 5: Customize Your Chart: Add labels, adjust colors, and tweak other visual elements to make the chart more understandable and visually appealing. This step also allows you to include additional features like tooltips, legends, and interactive elements.

Sankey charts come in several types, each with its own method of visual representation:

1. Basic Sankey Chart: This type of Sankey chart shows simple flows from start to end nodes. It’s great for showing basic data flow such as energy usage or material flow lines in a production system.

2. Clustered Sankey Chart: In this variant, flow lines can cross and go through multiple paths before reaching the end node. This type of chart helps to illustrate more complex systems and the interconnections between different flows.

3. Tree-like Sankey Chart: This chart is similar to a basic Sankey chart but focuses on branches and sub-flows, especially when one or more flow paths diverge to several nodes before reaching the end. It’s useful for showing hierarchical data flows, such as in organizational structures or supply chains.

4. Interactive Sankey Chart: While not a type of chart in its own right, interactive elements can be added to any Sankey chart, making it more engaging. Users can hover over nodes or links to get more detailed information or even click to explore specific paths.

5. Time-Lagged Sankey Charts: This variation shows how the flow changes over a period, making it ideal for studying trends and shifts in system behavior over time.

Now, let’s delve into some of the applications of Sankey charts:

Energy Flows

In the energy sector, Sankey charts are often used to visualize the complex process of energy generation, distribution, and consumption. They help in identifying the most significant energy sources and sinks, improving energy management, and assessing the impact of various policies or investments.

Supply Chain Analysis

For businesses, Sankey charts provide insights into the flow of goods and services, inventory, or financial transactions. This visualization can help in identifying bottlenecks, optimizing logistics, and enhancing resource allocation.

Network Traffic Analysis

In IT, Sankey charts can be used to map the flow of data traffic between different network nodes or IP addresses. This helps in understanding usage patterns, optimizing network performance, and detecting unusual activities.

Epidemiological Models

Sankey diagrams can also be employed in epidemiology to illustrate the spread of diseases between different population groups, the efficacy of interventions, or the transmission routes within a population.

Environmental Studies

In environmental science, Sankey charts can be utilized to depict the flow of materials (such as pollutants or nutrients) within ecosystems, helping in identifying sources, sinks, and the overall impact of human activities on the environment.

In conclusion, Sankey charts are an incredibly versatile tool that can be applied in various fields to visualize and analyze complex systems and data flows. Its ability to represent the transfer and transformation of items through various stages makes it an essential instrument for anyone interested in gaining a deeper understanding of interconnected processes. With the right software and a bit of creativity, Sankey charts can be customized to suit almost any data visualization need, providing valuable insights and actionable information. As data complexity and interconnectedness increase, the use of Sankey charts is likely to become even more widespread, making them a critical part of the data visualization repertoire.

SankeyMaster

SankeyMaster is your go-to tool for creating complex Sankey charts . Easily enter data and create Sankey charts that accurately reveal intricate data relationships.