Flow Visualized: The Art & Utility of Sankey’s Streamlined Storytelling
Imagine data and energy as fluid stories with their own movements and meanings, tracing paths through complex systems. This is the world of Sankey diagrams, powerful visual tools that offer a unique way of illuminating the flow of things. In this article, we delve into the creation of Sankey charts, their applications, and why they’re becoming an essential part of modern data storytelling.
The Genesis of the Sankey Diagram
Sankey diagrams are named after English engineer William D. F. Sankey, who patented the concept in 1898. Sankey’s diagram depicted the energy flow in a steam engine. This flow is illustrated as arrows that expand and contract according to the amount of material or energy being conveyed. Sankey diagrams are often described as a ‘storytelling device’ because they are able to convey large amounts of data in an intuitive and visually appealing way.
Key Characteristics of Sankey Diagrams
The defining features of Sankey diagrams include:
- Energy or Material Flow: They depict the flow of materials, energy, or costs through a process or system.
- Magnitude Representation: The width of each arrow increases as the amount of material, energy, or cash entering and leaving a part of the system grows, creating an intuitive representation of the relative magnitude of flows.
- Energy Efficiency: They typically use flow width to indicate the efficiency of processes since a wider arrow path represents more efficient energy use and less waste.
Creating Sankey Diagrams
Creating a Sankey diagram requires a few steps:
1. Gather Data
Collect data on the flow of energy, materials, or money through the system you want to represent. Understand the inputs, processes, and outputs in your network.
2. Identify Nodes and Links
Identify the nodes, which are the individual components, and the links, which describe the relationships between nodes and the amount of flow between them.
3. Choose Software or Tools
There are several tools available for creating Sankey diagrams, from simple free online generators to dedicated software. Common tools include Sankey.js, Gephi, Matplotlib, and Sigma.js. Choose a tool that fits your data requirements and your design aesthetic.
4. Map Data to Nodes and Links
Use your data to define the nodes and links on your diagram. Assign values to each link that reflect the volume of flow and use these to set the width of the arrows.
5. Customize the Design
Tailor the design to enhance story readability. This could include selecting a color scheme that aligns with your brand or the context of the data, adding labels for clarity, and experimenting with font styles and sizes.
Applications of Sankey Diagrams
Sankey diagrams are employed in a variety of fields for their ability to visualize complex data:
1. Energy Systems
They are widely used in the energy sector to show the energy conversion and losses within power plants and to illustrate the energy flow in buildings.
2. Environmental Studies
Sankey diagrams help to model the flow of pollutants in ecosystems, showing how materials enter, circulate, and leave the system.
3. Business and Economics
These diagrams showcase the flow of goods, money, and information in businesses, providing a clear picture of an organization’s financial flows or the movement of products.
4. IT Systems
In IT, they can visualize the flow of data or the efficiency of computing systems, helping to pinpoint bottlenecks.
5. Urban Planning
Sankey diagrams are used in transportation planning to illustrate and understand the flows of passengers and vehicles.
Concluding Thoughts
Sankey diagrams are a unique storytelling method for illustrating the movement and conversion of energy, material, costs, and more within a system. Their artistry lies in simplifying complex systems to enhance understanding. As data science permeates more aspects of daily life, the utilization of Sankey diagrams in data visualization will continue to grow. For those looking to present data with a story and a point of view rather than merely numerical data, Sankey diagrams stand out as a powerful and elegant solution.
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.
