Energy Flow Diagram: Step by Step Creation & Examples

You will agree with us when we say:

It’s INCREDIBLY hard to visualize data with energy flow characteristics.

It turns out there’s a chart that’s strategically positioned to visualize data with flow characteristics. Besides, this chart is amazingly easy to read and interpret. The chart we’re talking about is called an energy flow diagram.

So if you intend to create a compelling data story for your audience, you don’t have to worry. Yes, don’t worry about the best chart to use to present your insights to the audience.

This blog will walk you through energy flow diagram examples, how to use them to uncover patterns in your data, practical use, and, most importantly, the best visualization tool to use.

You don’t want to miss this if you plan on taking your data storytelling skills to the expert level by using a visualization, too, which we will discuss later in this blog.

Let’s get right into it.

What is an Energy Flow Diagram (EFD)?

Definition: An Energy Flow Diagram (EFD) is a visual tool used to show how energy moves through a system, process, or organization from input to output. It illustrates energy sources, transformations, losses, and end uses, helping users understand where energy is consumed efficiently and where waste occurs.

Typically represented with proportional flows or bands, an EFD makes it easy to compare energy quantities across stages. These diagrams are widely used in manufacturing, utilities, sustainability reporting, and energy audits to analyze performance and identify optimization opportunities.

By clearly mapping energy pathways, an Energy Flow Diagram supports data-driven decisions aimed at reducing costs, improving efficiency, and meeting environmental or regulatory goals.

Video Tutorial: How to Create an Energy Flow Diagram in Google Sheets?

In the following video, you will learn how to create an energy flow diagram in a few clicks without coding.

Why is an Energy Flow Diagram Important?

An Energy Flow Diagram visually shows how energy moves through a system, making sources, usage, and losses easy to understand at a glance. Unlike a basic data flow diagram, it highlights volume and direction, and when shown as an Energy Flow Chart using a graph maker, it enables clearer analysis and communication for all teams.

• Clear Energy Distribution: Visually shows how energy is generated, transferred, and consumed across different stages or components of a system.
• Loss Identification: Makes inefficiencies and energy losses easy to spot, helping teams target areas for improvement.
• System Comparison: Enables side-by-side comparison of processes, time periods, or scenarios to evaluate performance changes.
• Decision Support: Provides actionable insights that support planning, optimization, and resource allocation decisions.
• Stakeholder Clarity: Translates technical energy data into visuals that are easy for stakeholders to understand and discuss.
• Performance Tracking: Helps monitor trends over time, supporting continuous improvement and reporting.

Key Features of Energy Flow Diagrams

An Energy Flow Diagram highlights how energy moves between sources, processes, and outputs, making complex systems easier to understand at a glance. An Energy Flow Diagram focuses on proportional flows, clear relationships, and visual balance to support fast analysis.

• Proportional Flow Widths: Band thickness scales with energy volume, helping users instantly compare major and minor contributors.
• Clear Nodes and Paths: Distinct nodes represent stages, while connecting paths show direction and transfer between components.
• Directional Insight: Arrowed flows reveal where energy originates, how it transforms, and where losses occur.
• Comparative Analysis: An Energy Flow Chart allows side-by-side evaluation of inputs, conversions, and outputs within one view.
• System-Level Clarity: Works well for charting and graphing complex processes without overwhelming the audience.
• Broad Applicability: Fits many scenarios and complements other types of data visualization charts for reporting and dashboards.

Types of Energy Flow Diagram

An Energy Flow Diagram is a visual representation that shows how energy moves through a system, helping identify inputs, outputs, and losses through clear visual storytelling. It provides clarity on the efficiency of energy use and is widely used in engineering, environmental studies, and industrial processes.

Unlike a standard Energy Flow Chart, which may simply list sources and sinks, an Energy Flow Diagram highlights the quantitative or proportional flow of energy between components, making it easier to analyze complex systems.

• Sankey Energy Diagram: Shows energy quantities proportionally using arrow widths.
• Process Flow Diagram: Focuses on energy transformations within industrial processes.
• System Boundary Diagram: Illustrates inputs and outputs across defined system limits.
• Exergy Flow Diagram: Highlights energy quality and potential for useful work.
• Cumulative Energy Diagram: Tracks total energy consumption over time.
• Hybrid Flow Chart: Combines graphical and tabular data for clarity.

Energy Flow Diagram Examples

The chart visualizes the flow of material, energy, cost, or any measurable resource. Besides, it draws the attention of the audience to the most significant flows, consumers, losses, etc.

Remember, you can also call it an energy flow diagram or a Sankey Diagram.

Example# 1

This chart uses links and nodes to communicate insights. Essentially, the width of a flow is proportional to its quantity. The key to reading and interpreting the chart is remembering that the width is proportional to the quantity represented.

Example# 2

As we said earlier, the energy flow chart summarizes all the energy transfers in a process. Keep in mind: the thicker the line or arrow, the greater the amount of energy involved. Take a look at the energy flow chart example above.

It visualizes the domestic use of power in a home. The 3 main categories of the chart include the following:

• The main source
• Rooms
• Devices

Let’s analyze the chart real quick.

• The biggest energy consumers (in the devices category) in the home are the AC, oven, and stove.
• The biggest consumer of energy (in the rooms category) in the home is the kitchen.

How to Create an Energy Flow Diagram (Step-By-Step)?

Imagine you’ve been tasked by the Energy Commission of a hypothetical country to analyze its gigantic data through data analysis. They want to know various details about domestic energy consumption, namely:

• The contribution of each energy-generating source
• The amount of energy lost
• The energy contribution of cleaner and greener sources
• Common uses of energy by consumer segments (commercial versus domestic use)

The Energy Commission wants a data story to use for the forthcoming launch of its 10-year Plan. The table below has the sample data we’ll use for the scenario above.

Simple Energy Flow Diagram

If you have not installed the ChartExpo in Google Sheets yet, then you are missing a lot of visualizations to be explored. You can create many complex visualizations in a few clicks without coding using the ChartExpo Add-on.

To Get Started with the ChartExpo for Google Sheets Add-on, follow the Simple and Easy Steps Below.

• Open your Google Sheets application.
• Open the worksheet and click on the Extension menu.
• Once the Charts, Graphs & Visualizations by ChartExpo drop-down menu shows, click the Open button.

• Now you can start using ChartExpo for Google Sheets
• Click on the Add New Chart to continue, as shown below:

• You’ll see a list of visual charts.

• You can copy your data sheet and then select the chart from the list.

• Select the Sheet Name, and then click on Add new metric. In our case, the primary metric is energy value in megawatts.
• Click on Add new dimension and then add the variables: Energy Type, Main Source, Source Type, Energy Source, Usage, and End User.
• Click on Create Chart, as shown below.

• Let’s check out the resulting chart.

• This is how you will have the first look at your visualization based on your data. Now you can click on any node to change the position according to your requirements. You can even click on the Edit Chart button to see different properties like changing colors, etc.

• Once you select all the colors and put a heading according to your needs, you will get the final look as shown below.

Source: chartexpo.com

Insights:

• A huge chunk of Nuclear energy is getting wasted. The good news is that only 26% of the country’s overall energy needs are harnessed from nuclear sources.
• 36% of the country’s energy comes from greener sources.

Applications of Energy Flow Diagram

An Energy Flow Diagram is a visual tool that shows how energy moves through a system, highlighting losses, conversions, and efficiencies. A clear diagram of Energy Flow helps engineers, scientists, and decision-makers optimize energy use and understand complex systems.

These diagrams are widely used across industries for analysis, planning, and sustainability. The following are common applications of an Energy Flow Diagram:

• Industrial Efficiency Analysis: Identifies energy losses in manufacturing and helps improve process efficiency.
• Power Plant Optimization: Assesses energy inputs and outputs to enhance performance and reduce waste.
• Building Energy Management: Guides energy-saving measures and HVAC optimization in large facilities.
• Renewable Energy Planning: Visualizes energy conversion and integration in solar, wind, and bioenergy systems.
• Environmental Impact Assessment: Evaluates energy consumption and emissions for sustainable planning.
• Educational & Research Tool: Helps students and researchers understand energy transfer principles in physics and engineering.

Benefits of Using Energy Flow Diagram

An Energy Flow Diagram is a visual tool that illustrates how energy moves through a system, making it easier to understand complex processes through effective data visualization.

This diagram of Energy Flow helps identify inefficiencies and optimize energy use. Using an Energy Flow Diagram provides several advantages for engineers, managers, and researchers.

• Clarity of Energy Movement: Shows how energy enters, transforms, and exits a system.
• Identifying Losses: Highlights areas where energy is wasted or underutilized.
• Improved Decision-Making: Supports data-driven decision-making for energy efficiency and resource management.
• Simplified Communication: Makes complex energy interactions easy to explain to stakeholders.
• System Optimization: Helps prioritize improvements and optimize energy usage in processes.
• Comparative Analysis: Allows comparison of different energy pathways or scenarios for better planning.

FAQs

What are the 4 stages of energy flow?

1. Energy Input: Energy is introduced into a system from external sources (e.g., sunlight, fuel).
2. Energy Conversion: Energy is transformed from one form to another (e.g., chemical to thermal energy).
3. Energy Transfer: Energy moves through the system to where it is needed.
4. Energy Output: Energy is used to perform work or is released as waste (e.g., mechanical work, heat).

How does an energy diagram work?

An energy diagram visually represents the flow of energy through a system. It shows energy inputs, transformations, transfers, losses, and outputs, helping to track energy use, identify inefficiencies, and optimize performance.

The diagram typically uses arrows, symbols, and labels to illustrate how energy moves and changes form within the system.

Wrap Up

As we said earlier, you don’t have to struggle to visualize data with energy flow characteristics.

Use the energy flow diagram to visualize this type of data because it’s amazingly easy to read and interpret, especially in data stories. The flow diagram visualizes the flow of material, energy, cost, or any measurable resource.

The key to reading and interpreting the diagrams is noting that the width is proportional to the quantity represented.

If used effectively, it’s arguably the best visualization to use in a data story, especially when formulating energy policies for a country or state.

With the energy flow diagram, you can achieve the following:

• Quick trends, flows, and patterns analysis
• Uncover productivity and efficiency insights
• Create compelling reports
• Clarity and simplicity, especially when communicating key insights

The best tool to use to create Energy Flow Diagrams is ChartExpo. Sign up today to visualize energy flow data without having to waste your valuable time.