How to Use Energy Flow Diagrams (Sankey Charts) to Tell Data Stories?

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 (Sankey chart).

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 visualization tool which we will discuss later in this blog.

Let’s get right into it.

What is an Energy Flow Diagram?

Debunking the Definition!

An energy flow diagram (or Sankey) tracks the energy flow from raw or primary sources of energy up to the final stage (consumption).

In other words, a Sankey Diagram is a directional flow chart where the width of the streams is proportional to the quantity of flow. And where the flows can combine, split, and be traced through a series of events or stages.

Flows in the diagram can show energy, materials, fluids, or costs.

In this blog, we’ll focus primarily on energy flow. Note: the term ‘energy flow diagram’ is synonymous with ‘Sankey Charts.’

The Sankey chart visualizes energy and its transformation visually and quantitatively. And this includes primary energy (raw energy materials) fed into a system, energy supply, transformation, losses, and uses.

So, 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.

Take a look at the energy flow diagram example below:

• Primary sources of energy include coal, crude oil, natural gas, solar energy, etc.
• The primary sources convert to secondary energy, e.g., electricity, diesel, petrol, etc.
• The secondary energy converts to the final (energy received by consumers), as shown above.
• Note losses, especially when energy is flowing from one stage to the other.

Let’s understand the definition of a Sankey Chart.

What is a Sankey Diagram?

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

Remember, you can also call it an energy flow diagram.

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 Sankey Diagrams is remembering that the width is proportional to the quantity represented.

Note: The width of the lines and arrows represent amounts or volumes of resources.

The Power of Sankey Chart in Visualizing Energy Flow

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.

Telling Data Stories using Energy Flow Diagram Examples

Imagine you have energy flow data, and you want to craft a compelling data story for your audience.

Your audience could be policymakers, top management, or other key stakeholders in the energy sector.

So, where do you start?

Picking the best chart to visualize your data is one of the most challenging tasks to undertake. You have to test for the best one.

Use the Sankey chart if your primary goal is to have simple and clear charts that complement your data story seamlessly.

Sankey chart is arguably the best visualization to use to visualize complex data, such as energy flow.

This chart helps you tell your story in different ways, namely:

• Pattern and Trend Analysis: Use Sankey charts to visualize production, usage, losses, and cost analyses of energy. IF you analyze Sankey side by side if you have old data visualization and new data, you can infer it for forecasting purposes as well.
• Uncover Productivity and Efficiency: The main focus of any visualization is to empower optimization in productivity and efficiency. With energy flow charts, your audience can identify the most productive and efficient sources and consumers of energy.
• Improves Reporting: Data storytelling in reports is the most obvious use of data visualizations. A Sankey Diagram improves your report by providing key insights in the simplest way possible.

Essentially, your readers won’t struggle to understand the key insights forming the backbone of your data story.

• Promotes Simplicity and Clarity: As we said earlier, Sankey charts lend clarity and simplicity. Essentially, even non-technical audiences can understand your data story if you use this chart strategically.

How can you Uncover Hidden Patterns in Data using a Sankey Chart?

There are many different methods of visualizing data to identify patterns in your data.

However, selecting the best chart to compliment your data story is influenced by your goals, and most importantly, the nature of the dataset.

If you have complex data that you suspect has some flow characteristics, use a Sankey Chart.

Thank us later.

Why?

This chart strategically uses colors, flows, and nodes to provide hidden, in-depth insights into your data.

Your team or company wants to make critical decisions associated with the following: energy, time, or money.  Advise them to use the Sankey Diagram.

Why?

A Sankey Chart will not only uncover hidden patterns in your data but also provide you with high-level insights. Essentially, it’ll paint a vivid picture of what’s going on using colors, nodes, and flows.

Why are these charts great for you?

This chart allows you to show complex processes visually with the focus on a key insight you want to highlight.

Secondly, a Sankey Diagram supports multiple viewing levels. And this means your audience can get high-level insights as aligned with the goal of your data story.

Use this chart if you want your audience to identify dominant contributors or consumers and their relative magnitudes without struggle.

Use a Sankey Diagram if you want to enjoy the following insight-driven benefits:

• Correlations in Relationships: It’s incredibly challenging to identify the correlations and relationships of independent variables in complex data, such as energy flow.

Use a Sankey chart to make sense of the independent variables in your data.

• Macro-view of Data: Sankey Diagrams provide you with a high-level view of the best and worst-performing categories in your data.

Is it Important to Find Hidden Patterns in your Data?

Let’s face it.

Why do you collect data?

Yes, it’s to find patterns in your data.

What patterns?

We’re talking about trends, which can be upwards or downwards. Or correlations (relationships) between variables (dependent and independent variables).

Essentially, a pattern is a series of data that repeats recognizably.

Sometimes it’s easy to spot a pattern using simple tables. Conversely, depending on your goal or data set’s size, it helps to visualize using a chart.

The Best Tool for Creating Sankey Diagram

Data is the new gold in today’s world.

Data-driven companies may lose to know the process flows and many other opportunities if they don’t use a Sankey Diagram. A Sankey chart comes loaded with competitive advantages that can make or break the business analysis.

Remember, there are no shortcuts in making profitable decisions in today’s world. Yes, without visualizing the data.

ChartExpo offers immersive dashboards, which can make a massive difference in the way data visualization impacts your business.

Besides, it’s the best data visualization tool in the industry.

It comes loaded with different types of charts which can be used to create insightful dashboards. And this is to help you uncover hidden patterns within your company’s data.

Energy Flow Chart Example

Imagine you’ve been tasked by the Energy Commission of a hypothetical country to analyze their gigantic data. 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 their 10-year Plan. The table below has the sample data we’ll use for the scenario above.

Note: the table below is pretty long to show you that Sankey can visualize gigantic data sets without obscuring key insights.

Apologies in advance if you find the table below weirdly long.

Energy Type	Main Source	Source type	Energy Source	Usage	End-User	Megawatt
Agricultural waste	Bio-conversion	Solid	Thermal generation	Losses in process	Lost	5
Agricultural waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Industry	7.3
Agricultural waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – commercial	5.1
Agricultural waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – homes	3.7
Agricultural waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – commercial	4.9
Agricultural waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – homes	2
Other waste	Bio-conversion	Solid	Thermal generation	Losses in process	Lost	7.2
Other waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Industry	5.4
Other waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – commercial	6.7
Other waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – homes	4.8
Other waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – commercial	7.4
Other waste	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – homes	2.5
Marina algae	Bio-conversion	Solid	Thermal generation	Losses in process	Lost	0.7
Marina algae	Bio-conversion	Solid	Thermal generation	Electricity grid	Industry	0.5
Marina algae	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – commercial	0.9
Marina algae	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – homes	0.5
Marina algae	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – commercial	0.8
Marina algae	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – homes	0.6
Land-based bioenergy	Bio-conversion	Solid	Thermal generation	Losses in process	Lost	1.3
Land-based bioenergy	Bio-conversion	Solid	Thermal generation	Electricity grid	Industry	2.5
Land-based bioenergy	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – commercial	3.2
Land-based bioenergy	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – homes	0.7
Land-based bioenergy	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – commercial	1.4
Land-based bioenergy	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – homes	0.9
Biomass import	Bio-conversion	Solid	Thermal generation	Losses in process	Lost	0.4
Biomass import	Bio-conversion	Solid	Thermal generation	Electricity grid	Industry	0.7
Biomass import	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – commercial	0.8
Biomass import	Bio-conversion	Solid	Thermal generation	Electricity grid	Heating and cooling – homes	0.3
Biomass import	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – commercial	0.6
Biomass import	Bio-conversion	Solid	Thermal generation	Electricity grid	Lighting & appliances – homes	0.2
Nuclear reserves	Nuclear Plant	Solid	Thermal generation	Losses in process	Lost	50
Nuclear reserves	Nuclear Plant	Solid	Thermal generation	Electricity grid	Industry	13
Nuclear reserves	Nuclear Plant	Solid	Thermal generation	Electricity grid	Heating and cooling – commercial	8
Nuclear reserves	Nuclear Plant	Solid	Thermal generation	Electricity grid	Heating and cooling – homes	6
Nuclear reserves	Nuclear Plant	Solid	Thermal generation	Electricity grid	Lighting & appliances – commercial	11
Nuclear reserves	Nuclear Plant	Solid	Thermal generation	Electricity grid	Lighting & appliances – homes	4
Coal reserves	Coal	Solid	Thermal generation	Losses in process	Lost	4.7
Coal reserves	Coal	Solid	Thermal generation	Electricity grid	Industry	3.1
Coal reserves	Coal	Solid	Thermal generation	Electricity grid	Heating and cooling – commercial	4.2
Coal reserves	Coal	Solid	Thermal generation	Electricity grid	Heating and cooling – homes	0.7
Coal reserves	Coal	Solid	Thermal generation	Electricity grid	Lighting & appliances – commercial	4.8
Coal reserves	Coal	Solid	Thermal generation	Electricity grid	Lighting & appliances – homes	0.5
Gas reserves	Natural Gas	Gas	Thermal generation	Losses in process	Lost	5.1
Gas reserves	Natural Gas	Gas	Thermal generation	Electricity grid	Industry	8.4
Gas reserves	Natural Gas	Gas	Thermal generation	Electricity grid	Heating and cooling – commercial	7.9
Gas reserves	Natural Gas	Gas	Thermal generation	Electricity grid	Heating and cooling – homes	4.8
Gas reserves	Natural Gas	Gas	Thermal generation	Electricity grid	Lighting & appliances – commercial	7.3
Gas reserves	Natural Gas	Gas	Thermal generation	Electricity grid	Lighting & appliances – homes	3.5
Green energy	Hydro	Dams	Electricity production	Losses in process	Lost	9.8
Green energy	Hydro	Dams	Electricity production	Electricity grid	Industry	7.5
Green energy	Hydro	Dams	Electricity production	Electricity grid	Heating and cooling – commercial	6.7
Green energy	Hydro	Dams	Electricity production	Electricity grid	Heating and cooling – homes	5.3
Green energy	Hydro	Dams	Electricity production	Electricity grid	Lighting & appliances – commercial	8.9
Green energy	Hydro	Dams	Electricity production	Electricity grid	Lighting & appliances – homes	6.8
Green energy	Tidal	Through Sea	Electricity production	Losses in process	Lost	0.3
Green energy	Tidal	Through Sea	Electricity production	Electricity grid	Industry	0.5
Green energy	Tidal	Through Sea	Electricity production	Electricity grid	Heating and cooling – commercial	0.4
Green energy	Tidal	Through Sea	Electricity production	Electricity grid	Heating and cooling – homes	0.1
Green energy	Tidal	Through Sea	Electricity production	Electricity grid	Lighting & appliances – commercial	0.5
Green energy	Tidal	Through Sea	Electricity production	Electricity grid	Lighting & appliances – homes	0.2
Green energy	Wave	Through Sea	Electricity production	Losses in process	Lost	0.8
Green energy	Wave	Through Sea	Electricity production	Electricity grid	Industry	0.7
Green energy	Wave	Through Sea	Electricity production	Electricity grid	Heating and cooling – commercial	0.9
Green energy	Wave	Through Sea	Electricity production	Electricity grid	Heating and cooling – homes	0.3
Green energy	Wave	Through Sea	Electricity production	Electricity grid	Lighting & appliances – commercial	0.5
Green energy	Wave	Through Sea	Electricity production	Electricity grid	Lighting & appliances – homes	0.3
Green energy	Wind	Wind Power Plant	Electricity production	Losses in process	Lost	3.7
Green energy	Wind	Wind Power Plant	Electricity production	Electricity grid	Industry	17.9
Green energy	Wind	Wind Power Plant	Electricity production	Electricity grid	Heating and cooling – commercial	18.1
Green energy	Wind	Wind Power Plant	Electricity production	Electricity grid	Heating and cooling – homes	5.8
Green energy	Wind	Wind Power Plant	Electricity production	Electricity grid	Lighting & appliances – commercial	5.5
Green energy	Wind	Wind Power Plant	Electricity production	Electricity grid	Lighting & appliances – homes	4
Green energy	Solar	Solar Power Plant	Electricity production	Losses in process	Lost	1.7
Green energy	Solar	Solar Power Plant	Electricity production	Electricity grid	Industry	5.9
Green energy	Solar	Solar Power Plant	Electricity production	Electricity grid	Heating and cooling – commercial	5.4
Green energy	Solar	Solar Power Plant	Electricity production	Electricity grid	Heating and cooling – homes	2.2
Green energy	Solar	Solar Power Plant	Electricity production	Electricity grid	Lighting & appliances – commercial	4.1
Green energy	Solar	Solar Power Plant	Electricity production	Electricity grid	Lighting & appliances – homes	0.7

If you have not installed the ChartExpo in Google Sheets yet then you are missing a lot of visualization to be explored.

Let’s install ChartExpo Add-on and then use the visualization on this data.

Follow the incredibly simple and easy steps below to visualize

your data using Sankey Charts.

• Click on Add-ins> ChartExpo> Open> Sankey Charts

• Select Sheet Name, and then Add new metric. In our case, the primary metric is energy value in Mega Watts.

• 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 from sheet data, as shown below.

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

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

Insights:

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

36% of the country’s energy comes from greener sources.

FAQs:

What is an energy flow diagram?

The energy flow diagram visualizes what’s happening to a particular source of energy with regard to consumption and usage.

These diagrams can be extended to include other forms of energy, such as light, nuclear, electrical, and heat energy.

Why are Sankey Diagrams useful?

Sankey Diagrams visualize transfers or flow within a system. Besides, they help locate the significant contributors to a flow in your data.

This chart is arguably the best visualization to use to visualize complex data, such as energy flow. Use the Sankey chart if you want high-level insights into your data.

Why is the Sankey Diagram Useful in Energy Balance Calculations?

The Sankey Diagram comes in handy, especially if you want to visualize an entire input and output flow in a system, such as a boiler generator, to derive an energy balance equation.

What is the Sankey energy diagram?

Sankey Diagram is a directional flow chart where the width of the streams is proportional to the quantity of flow. And where the flows can combine, split, and be traced through a series of events or stages.

Wrap Up

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

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

The key to reading and interpreting Sankey 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 easy-to-read and interpret Sankey Diagrams is ChartExpo. Sign Up today to visualize energy flow data without having to waste your valuable time.