Flowing Insights: The Art of Decoding Sankey Diagrams

Sankey diagrams, also known as Sankey plots or flow diagrams, are a specific type of flow visualization tool that displays the quantity of material, energy, or cost involved in production processes, engineering systems, or biological processes. With their distinctive streamlines and directionality, Sankey diagrams are an essential tool for anyone seeking to understand complex systems where flow rates and energy are critical aspects to analyze. Here, we delve into the art of creating and decoding Sankey diagrams, unveiling their unique applications across numerous fields.

Understanding Sankey Diagrams

Sankey diagrams are named after the German engineer, Carl Wilhelm von Langsdorf, who described a similar visualization method. However, the name was popularized by Max Schmid, another engineer, who incorporated this concept into a more systematic approach for representing energy flows. Essentially, a Sankey diagram consists of a series of horizontal arrows that “flow” from a source to a destination, with the width of each arrow representing the quantity of material, energy, or cost being transferred.

Key Characteristics of Sankey Diagrams:

1. Energy Flow: Sankey diagrams are renowned for their ability to represent the flow of energy—be it physical energy or economic cost—across various processes.

2. Streamline Representation: The flow through and between processes is depicted as a series of arrows, making the diagram intuitive and easy to interpret.

3. Flow Width Correlation: The width of the energy flow arrows directly correlates with the quantity of energy involved, allowing the viewer at a glance to discern the efficiency of energy conversion.

4. Dynamic and Directional: The arrows’ directionality indicates both the direction of energy flow and the processes involved, and changes can be depicted as the flow adjusts over time.

The Art of Creating Sankey Diagrams

Crafting a Sankey diagram is not solely an art, but it requires a balance of thoughtful design, precise input, and a clear understanding of the system being visualized. Here are some steps to design Sankey diagrams effectively:

1. Define the System: Establish the boundaries of the system and clearly outline the processes involved.

2. Quantify the Data: Obtain the necessary flow rates and convert these numeric values to corresponding widths for the flow arrows.

3. Identify Nodes: Nodes, or intersections, are critical for making connections between flows and allowing for more complex systems to be visualized.

4. Choose the Software: Select a software or tool that is designed for Sankey chart creation, such as Microsoft Visio, specialized Sankey diagram software, or open-source tools like matplotlib and SankeyLab for Python users.

5. Design and Arrange: Start with the primary flows and add the detail as necessary, ensuring the diagram remains clear and readable.

6. Review and Revise: It’s crucial to review the diagram for any discrepancies, readability, and to ensure the information conveyed is accurate.

The Applications of Sankey Diagrams

Sankey diagrams are employed across a wide range of fields for their ability to provide a clear and actionable insight into complex flow systems. Some examples include:

Energy & Environment

• Visualizing energy use patterns in buildings and urban planning.
• Tracking material flows within global environmental systems.
• Monitoring and improving energy efficiency of industrial processes.

Engineering Systems

• Analyzing the energy consumption and production in power plants.
• Engineering heat recovery and waste minimization efforts.
• Enhancing the energy management of transportation systems.

Finance & Economics

• Mapping financial flow and illustrating supply chains in investment portfolios.
• Presenting cost breakdowns in products and services or for project workloads.
• Understanding the flow of capital across various markets and sectors.

Biological Systems

• Observing the oxygen and chemical flow in biological reactions.
• Analysing nutrient cycles in ecosystems.
• Tracking energy pathways in living organisms.

In conclusion, the art of decoding Sankey diagrams is not just about comprehending the data represented but also about interpreting the underlying system behavior. By understanding and skillfully using the tools for creating Sankey diagrams, one can unlock valuable insights that could lead to improvements in efficiency, decision-making, and systems analysis. Through their unique ability to depict the quantity and flow of complex processes visually, Sankey diagrams continue to serve as a staple tool for those looking to comprehend and simplify intricate systems.

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.