Unraveling Complexity with Flow: A Journey through Sankey Chart Visualization

Sankey charts are powerful tools for visualizing complex systems in a way that is both informative and aesthetically pleasing. Originating from steamboat engineer Holger von Sankey, these diagrams provide a comprehensive, visual representation of the flow of ‘something’ from one point to another, making it easier to understand how things are distributed within a system.

In this article, we will delve into the creation and applications of Sankey charts, exploring how they are made, their unique benefits, and their wide range of uses across various fields.

What Are Sankey Charts?

Sankey charts, named after Holger von Sankey, are diagrammatic mappings of flows between nodes, where width of the arrows or bands is proportional to the flow quantity between the nodes. Each node represents a state, and the width of the arrows connecting the nodes reflects the magnitude of the flow.

How to Create a Sankey Chart

Creating a Sankey chart involves several steps:

1. Data Preparation: Gather the data that describes the flow between your categories. This data typically consists of pairs of categories and the volumes or percentages of flow between them.

2. Choose a Tool: Many software tools support Sankey charts, including Tableau, Microsoft Power BI, and specific libraries for programming languages. For instance, in Python, you might use the sankey module in the networkx library or specialized libraries like D3.js for web-based charts.

3. Visualization: Input your data into the chosen tool. Here, you’ll design the layout, typically using a set of parameters such as the direction of flows (top-to-bottom), colors to represent different categories, and the thickness of the links to indicate the data volume.

4. Customization: Enhance the chart by personalizing colors, labels, and adding tooltips to provide more context to those who view the chart.

5. Review and Finalize: Check the accuracy and readability of the chart. Ensure that the visualization effectively communicates the flow dynamics and any significant outcomes.

Applications of Sankey Charts

Sankey charts are versatile tools with applications across multiple fields, including:

Energy Systems

In the realm of energy, Sankey charts are invaluable for depicting energy usage, conversion, and distribution systems. For example, they illustrate how energy flows through different stages, such as from fossil fuels to electricity generation and distribution, to end-user consumption.

Waste Management

Waste management authorities utilize Sankey charts to track the movement of waste from source to recycling, composting, and incineration. This visualization aids in identifying the most dominant waste streams and possible areas for improvement in waste reduction and recycling efforts.

Supply Chain Analysis

Supply chain managers benefit from Sankey charts that show the flow of products or materials across different stages, from sourcing raw materials to final distribution. This allows for more efficient allocation of resources and pinpointing bottlenecks in the supply chain.

Financial Flows

In finance, Sankey charts are used to visualize cash flows, risk management processes, and budget allocations. They provide clear insights into complex financial transactions and can be instrumental in budgeting and financial planning.

Social Sciences

In the social sciences, Sankey charts can map out the flow of individuals between different income brackets, educational pathways, or social mobility data. This helps researchers understand demographic trends and patterns of movement.

Environmental Studies

For environmental studies, Sankey charts can visually represent the carbon flow in ecosystems, tracking the sources of emissions and their impacts across different sectors like agriculture, energy, and transportation.

Conclusion

Sankey charts are an essential visual tool for unraveling complexity through the representation of flow in systems. They are not only informative but also visually appealing, making them accessible for a wide audience. Whether tracking the progression of a city’s budget, visualizing the traffic of internet data, or understanding the intricacies of the global market, Sankey charts offer a clear, comprehensive view. By choosing the right tool and carefully designing the visualization, you can create effective Sankey charts that enhance the visibility and understanding of flow dynamics in your specific application.

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.