SankeyMATIC Gallery: Energy Flows

Reworking a well-known example

Complex Sankey diagram showing energy flows of many kinds. This diagram depicts a potential scenario for UK energy production and consumption in 2050. The largest inputs represent Nuclear power (roughly 839 TWh) and Oil imports (504TWh). The largest output is the Losses path (878 TWh).

Original Diagram from Observable:

Sankey energy example: Original

Data Source: Department of Energy & Climate Change, Tom Counsell.

Diagram Notes: “This intricate diagram shows a possible scenario for UK energy production and consumption in 2050: energy supplies are on the left, and demands are on the right. Intermediate nodes group related forms of production and show how energy is converted and transmitted before it is consumed (or lost!).”

This energy dataset is used in the big library of D3 examples as a demonstration of D3's Sankey capabilities.

I have adapted the original inputs (found attached to the above page as energy.csv) to be in SankeyMATIC format; you can see the entire list below.

Some of the formatting changes I experimented with:

One interesting oddity about this diagram - when you enter all the original inputs into SankeyMATIC, several flows are called out as imbalanced:

Screenshot of a list of imbalances. The Total Inputs to the diagram add up to 2,842.038 and the Total Outputs sum to 2,840.703. The largest imbalance is on the Node named Electricity Grid, with 1.336 more Terawatt Hours flowing out of the Node than flowed in.

Regarding all the +/- 0.001 TWh differences: those are at the limit of the input data's precision and are easily considered rounding errors and not very important.

The more interesting line is the “Electricity grid” imbalance, which is noticeably larger.

I've tried to look into the original data, but haven't been successful in pinning down what may be missing. My theory is that since these are all projections, it's possible there was a slight miscalculation in the original spreadsheet.

Whatever the source, the error is still quite small: 0.15% of the total size of the “Electricity grid” node. The fact that the IN amount is less than the OUT amount by 1.336 TWh is barely even visible at this diagram size.

Summarizing:

You can copy & paste these inputs to SankeyMATIC to reproduce the above diagram:

See the Manual for more specific examples, or return to the Gallery home page, or go forth and try out a diagram of your own.