Flow Through Time: Mastering the Art of the Sankey Diagram

Sankey diagrams, first conceptualized in the late 19th century by Henry Dutton, are a type of flow diagram used to visualize the energy or material flows in a process or system. They have become invaluable tools in fields as diverse as industrial engineering, environmental science, and finance, as they provide a clear and concise summary of complex data flows.

The Evolution and Principles of Sankey Diagrams

Sankey diagrams derive their name from their inventor, Ernst Eduard Heinrich von Schlick (commonly referred to as Karl Wilhelm von Schlickey), who improved upon initial versions in his 1895 work “Energy Consumption of Manufacturing Industries.” Since then, their principles of simplicity and effectiveness have remained constant, while their digital iteration has multiplied rapidly with the advancement of computational capabilities.

Principles of a Sankey Diagram:

1. Flow Arrow Width: The width of the arrow corresponds to the quantity of material or energy flowing.
2. Direction: The flow of the arrow represents the direction of movement of the material or energy.
3. Flow Direction: The arrowheads indicate the direction of the flow within different processes or components.
4. Efficiency: The use of color gradients to represent the efficiency of a process — more color shows less efficient processes or a more substantial flow.
5. Flow Continuity: There should be consistency in the form of the process within each sub-system to avoid confusion.

Creation of Sankey Diagrams

Creating Sankey diagrams is a multi-step process that combines graphic design, data analysis, and systematic layout. Here’s a step-by-step guide to creating a Sankey diagram:

1. Define the System

Start by defining the system or process you want to analyze. Understand the inputs, outputs, and the internal processes involved.

2. Collect Data

Gather data about the system, usually in terms of the material or energy quantities, flow rates, and efficiencies.

3. Choose the Software

Select the appropriate software for creating Sankey diagrams. There are numerous tools available, from open-source libraries (like matplotlib for Python) to dedicated software (like SankeyLab or Sankey Studio).

4. Setup the Diagram

In your chosen software, create the general structure, setting up the diagram’s length, and the width of the initial and final elements.

5. Enter Data

Enter the data for the arrows, considering the flow width which indicates the flow quantity and the efficiency gradients.

6. Layout Elements

Arrange the elements within each subsystem and maintain logical connections between them.

7. Customize Appearance

Adjust the color, line styles, and arrow shapes to make the diagram as readable and informative as possible.

8. Review and Refine

Check for any omissions or errors, then refine the diagram to make sure it clearly conveys its intended message.

Applications of Sankey Diagrams

Sankey diagrams are applicable across a multitude of industries and scenarios:

Energy Systems and Sustainability

Sankeys are ideal for visualizing the flow of energy during various processes. They can help illustrate how energy is generated, distributed, and consumed, which is crucial for optimizing systems’ efficiency and reducing carbon footprints.

Environmental Science

Ecologists use Sankey diagrams to model ecosystems and understand the transfer of materials among various components within the system.

Industrial Processes and Logistics

The manufacturing, supply, and logistic sectors utilize Sankey diagrams to identify inefficiencies and bottlenecks in their processes, leading to smarter and more efficient system designs.

Economics and Finance

Financial analysts use Sankey diagrams to depict the flow of money within a company or economy, highlighting sources and uses of capital.

Data Science and Technology

In data science, Sankey diagrams can represent the flow of data between various processes during information retrieval and analysis.

In conclusion, Sankey diagrams facilitate a more profound understanding and simplified representation of complex data flows within processes. With the right approach, they can become a powerful tool in every analyst’s data visualization toolkit. By mastering the art of creating a Sankey diagram, one can break down intricate systems to their most fundamental flows, leading to insights that can drive changes for the better, from increasing operational efficiency to reducing environmental impact.

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.