Flow with Data: Mastering the Art of Sankey Charts

Sankey charts are visualizations that illustrate the flow of materials or energy through a system. They became famous for tracking the flow of resources in energy conversion or for visualizing supply chains in various industries. Known for their distinctive arrow-based representation that tapers according to the flow’s volume, Sankey charts are a powerful tool for understanding complex flows. In this article, we delve into the creation and applications of Sankey charts, illustrating how they can assist in mastering the art of data representation.

Understanding Sankey Charts

A Sankey chart consists of a series of horizontal and vertical links that connect nodes. These nodes represent a process or system component, and the links signify the flow of materials, energy, or resources between these components. The width of each link corresponds to the magnitude of the flow it represents, with wider links corresponding to higher flow rates, and the direction of the flow is shown by the direction of the link.

Key Features of Sankey Charts

1. Flow Magnitude: The width of the flow lines represents the flow magnitude, allowing viewers to quickly identify the major and minor flows.
2. Efficiency Insight: Sankey charts can highlight inefficiencies by showing larger volumes flowing between processes with less significant transformations.
3. Complexity Reduction: They distill complex data flows into a concise, visually comprehensible format.
4. Scalability: Sankey charts are scalable, capable of representing small datasets as well as large, complex systems.

Creating Sankey Charts

Creating Sankey charts involves several steps, though the exact process may vary with the software or tool you choose. Here are a general outline and some tips:

1. Gathering Data

Collect the data that reflects the flows you want to represent. This data may come from various sources, such as surveys, sensors, and process maps.

2. Identifying Nodes and Connections

Identify the nodes (components of your system) and connections (flows between them). Determine the direction of flow and the magnitude for each connection.

3. Selecting a Tool

Choose a Sankey chart tool. Excel has templates you can modify, or you can use specialized software such as Gephi, Sankey Diagrammer, or D3.js, which allow for more customization and interactivity.

4. Creating the Sankey Chart

• Start by setting up the nodes: Use the tool’s capabilities to create nodes and set their positions.
• Draw flow lines: Based on the data you gathered, create lines between nodes. Use the tool’s interface to adjust the line widths to reflect the flow magnitude.
• Adjust for direction: Ensure the direction of each line is correctly set to indicate the direction of flow.

5. Fine-Tuning to Convey Information

• Label appropriately: Clearly label each component and flow.
• Consider the color scheme: Use a distinct color for each type of flow or resource to help differentiate them.
• Ensure readability: Keep the chart clean and avoid cluttering with too much information.

Applications of Sankey Charts

Sankey charts have a vast range of applications across various fields:

Business and Economics

• Energy Efficiency: Showing how energy flows through a building or a supply chain.
• Financial Flows: Tracking how money moves between various accounts or departments.

Environment and Sustainability

• Carbon Footprint: Illustrating the flow of carbon dioxide through different stages of a manufacturing process.
• Waste Management: Tracking the flow of waste materials to understand their disposal and recycling patterns.

Science and Technology

• Reactions in Chemistry: Representing the flow of atoms between steps in a chemical reaction.
• Software Development: Showing the distribution of programming resources and the dependencies between modules.

In the age of big data and high-information complexity, Sankey charts are a valuable tool. Their ability to simplify complex data streams and make flow patterns apparent makes them an important part of a data professional’s toolkit. By mastering the art of Sankey charts, one gains the ability to communicate the hidden complexities of data flow with greater clarity and impact than ever before.

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.