Unraveling the Flow: The Sankey Chart Story
In an era of big data and complex information, visual storytelling has become more crucial than ever. Among the various means of conveying information, the Sankey chart stands out as a unique and highly effective diagram for illustrating the flow of energy, material, or process data. With their distinctive, flowing lines, Sankey diagrams provide a clear and concise overview of systems at a glance. Let’s explore the ins and outs of creating and applying Sankey charts in various contexts and scenarios.
What is a Sankey Chart?
A Sankey chart is a type of flow diagram often used to visualize the quantities of material, money, energy, or people moving between different processes or entities in a workflow. Characterized by their width, which represents the magnitude of the flow, Sankey charts are powerful tools for discerning the most significant areas of intensity and consumption.
Sankey charts were first developed by Irish engineer Matthew Sankey in 1898 to represent the energy flow in steam engines. Since then, their use has expanded vastly to encompass sectors in engineering, environmental studies, business intelligence, and more.
How to Create a Sankey Chart
Creating a Sankey chart requires careful crafting to accurately reflect the data at hand. Here’s a step-by-step guide to creating a Sankey chart:
1. Data Collection
Begin by gathering data on the flow you wish to represent. This could include energy usage, material flow, or any other process where quantities need to be tracked over different steps.
2. Define Nodes
Every Sankey chart consists of a set of interconnected nodes, which represent the processes or entities involved in the flow. Decide which processes are most relevant to your subject and map them onto the chart, making sure the connections between the nodes accurately represent the flow of the material or energy.
3. Assign Flow Values
Measure the magnitude of the flow through each part of the system. This is typically measured in units like energy, mass, or money.
4. Set Line Widths
Based on the measured flow values, assign the width of your lines. The wider the line, the greater the volume or flow. This visual indicator allows viewers to quickly identify the most and least significant flow segments.
5. Draw Nodes and Lines
Using a drawing tool or software that supports Sankey diagrams, begin to construct your nodes. Nodes can be represented by ovals, circles, or rectangles. Ensure that there is a clear connection between nodes, usually by drawing lines that look like streams, to show the direction of flow.
6. Connect Nodes with Flow Lines
Now, connect each node with a series of lines that represent the flow between them. The thickness of each line should scale to reflect the amount of flow passing through it.
7. Finalize and Review
Once the Sankey diagram is complete, review it for clarity and correctness. Adjust any lines or nodes if necessary, and ensure that the entire diagram accurately portrays the intended information.
Sankey Chart Applications
Sankey diagrams can be deployed across various applications, offering insights and communication benefits in the following areas:
1. Energy Analysis
Energy companies use Sankey diagrams to visualize energy flows in power generation systems, helping stakeholders understand how much energy is used in each step and where losses occur.
2. Process Mapping
Quality assurance professionals employ Sankey charts to map out manufacturing processes, highlighting bottlenecks and inefficiencies.
3. Financial Analysis
In finance and business, Sankey diagrams represent cash flows, illustrating how money moves through different departments or business lines.
4. Environmental Studies
Environmentalists use these charts to understand material and energy flows in ecosystems and to visualize the impact of human activities on the environment.
5. Traffic Analysis
Transportation planners use Sankey charts to illustrate the flow of traffic and can be used to help design more efficient road systems.
Conclusion
The Sankey chart has evolved since its inception over a century ago. Today, they remain an invaluable tool for visualizing the dynamic flows of energy, materials, and processes. With the right data and attention to detail, Sankey charts can transform complex information into a clear and compelling narrative. Whether you’re analyzing environmental flows, optimizing a business process, or illustrating the dynamics of your system of interest, the Sankey chart is sure to help you unravel the flow in an informative and engaging way.
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.
