Checking further on the authorship of the Sankey diagram I presented in this post, I came to the LCMP website at the University of Cambridge. LCMP? Yes … Low Carbon and Metals Processing. The engineering research group around Julian Allwood and Jonathan Cullen have three large research themes: WellFormed, WellMet2050, and WellMade.

The below Sankey diagrams are from the report ‘Going on a metal diet’ by Allwood, Cullen published within the WellMet2050 research theme.

The first Sankey diagram shows the global steel flows in 2007

the other the global aluminium flows in 2007:

One page 7 of the report the authors explain

“In our maps, the width of each line is proportional to the mass flow of metal. Values for the major flows are given in Mt (million tonnes). Steel flows less than 1 Mt and aluminium flows less than 0.05 Mt are not shown. Each major process step is shown as a vertical black line, with three possible outputs: useful metal (colored), process scrap (grey) and metal losses (black). Useful metal continues to flow to the next process step, while scrap loops back to the appropriate melting stage where it is recycled. Internal recycling loops, for example from the continuous casting processes for steel are shown small oval loops. (…)The working papers … give more detail about creating the Sankey diagrams

Unfortunately these two mentioned working papers are not (yet?) available on the website. These really fantastic Sankey diagrams have been compiled from different data sources. I thought I’d share them with you. Please visit the LCMP website and read about their other exciting projects.

Here is a tasty one … The Scottish whisky distillery of Balmenach has worked with the Energy Systems Research Unit at Strathclyde University in Glasgow to investigate the potential energy production from Whisky distillation co-products (such as draff, pot ale and spent lees). More information on this case study can be found here. Here is the Sankey diagram from this case study.

The study concludes that it would be advisable to feed the liquid co-products to an anaerobic digester to produce methane. A power generator can use this fuel to meet the electricity demand of the distillery, the surplus could be fed to the grid. Exhaust gases from the generator can be utilised by a waste heat boiler to offset the steam requirements of the stills. This would result in an annual economic benefit of £178,450 and a payback period of 5 years.

The Sankey diagram shows electric energy in MWh, co-products in tons per year, and biomass in cubic metres. Hence, these flows must not be compared to each other. I am unsure about the red arrow from the steam boiler to the distillery, which is labelled ‘18,841 MWh’ as it doesn’t seem to be to scale with the other energy flows.

Anyways. I like this one. Here’s tae us, wha’s like us? Damn few, and they’re a’ deid.

Typically it is quite difficult (read: expensive) to get hold of official ISO standards. It is by chance that I discovered the draft version of ISO 13579-1 on ‘Industrial furnaces and associated processing equipment — Method of measuring energy balance and calculating efficiency — Part 1: General methodology’ on the website of AFNOR, the French body of standards. The draft is open for comments as part of a public hearing process.

The draft standard ISO 13579-1 talks about energy balance (‘bilan énergétique’). Part 4.2 shows a sample Sankey diagram and explains that this is a tool that allows to represent the in and out flows of energy (‘outil permettant de représenter le flux d’entrée et de sortie de l’énergie’). In section 9 f on reporting the draft standard recommends that the report shall include a Sankey diagram (‘Il convient que le rapport de mesure du bilan énergétique contienne … Diagrammes de Sankey.’).

Didn’t have the original English version at hand, so I hope this is pretty much what it says in French.

Anyone aware of other ISO standards that mention Sankey diagrams?

Two Sankey-style diagramming tools which I have shamefully neglected until today are ParSets and Fineo. Both visualization tools have been released to the public in 2009 (first publication on ParSets in a research paper in 2006, predecessor project of Fineo, the Design Research Map project first mentioned in 2008). The main idea behind both tools is to visualize statistical data by grouping it into categories and showing bands/streams/parallelograms between the categories to represent the relationships between the categories.

ParSets and Fineo have similarities and differences. But before we go into details, let’s have a look at both tools first. Here is a screenshot from ParSets:

And here is one from Fineo:

ParSets was developed by Robert Kosara (Department of Computer Science, College of Computing and Informatics, University of North Carolina at Charlotte) and Caroline Ziemkiewicz (Brown University). The tool is open source and runs on Mac and Windows platforms. Read more about ParSets on the project page on Robert’s EagerEyes blog. The project had some funding from the U.S. Department of Homeland Security, and the tool is designed to work on census data or other statistical data.

Fineo was developed by the DensityDesign group, a Research Lab in the design department (INDACO) of the Politecnico di Milano in Italy. This is an online tool and can be used by uploading csv data files. Try the online version here, or visit the project page on the Density Design blog. This is a self-sponsored project, targeting at designers and infographers.

There are some differences in the layout and design. ParSets shows the link between categories as parallelograms, while Fineo has curved bands. The main orientation of the diagram is top-to-bottom in ParSets, and left-to-right in Fineo. Hence the nodes (representing categories) are thin horizontal lines in ParSets, and vertical black bars in Fineo. Not sure, but this is probably an option setting.

The main difference though seems to be that ParSets keeps track of subdivisions over neighbouring categories. Fineo looks more at pairs of categories (category – relation – category) and is according to the authors more inspired by this feature of Sankey diagrams (read here). On a side note I would like to add to this that both ParSets and Fineo lack one important of characteristic of Sankey diagrams, which differentiates them from Sankey diagrams: flow direction, or, in other words, a ‘from-to’ relationship. “Both of the visualizations are weighted bipartite graphs”, but not directed graphs.

Still, both tools are very good pieces of work, and I am looking forward to seeing updates in the future.

After my last post on the Paris Urban Metabolism I continued to research that topic a little more. I came across another example from France. The below Sankey diagram is from an article on territorial metabolism in the rural village of Contres in France. (“H4 développe une démarche de métabolisme territorial à Contres”).

In this study, the consultant company H4 Valorisation analysed the material and energy flows liked to the villages economic and agricultural activities. Different scenarios were evaluated, focusing primarily on (1) reducing imports and rejects (waste and pollutants), (2) increasing usage of local resources, and (3) looking at reuse of material internally (les rebouclages internes).

The Sankey diagram shows both mass and energy in one diagram, so the inputs and outputs of the central node (representing the village of Contres) are not balanced when summed up. Mass flows are in tons (per year?) in blue and red colors. Energy is in Mwh per year and shown in orange color. Greenhouse gas emissions from energy used is also represented in pale yellow expressed in tonnes of CO2-equivalents.

Reblogged from ‘I Love Charts’ blog, an absolute cutie:

I used to hang out with this guy who I thought was really sweet. We always hung out together because we were working on a group project that involved sankey diagrams, so before I had to delete the software, I made this diagram of all our shenanigans which, as you can see, involved us making acting like we were 10. I guess he lost interest so I never had the opportunity to send it to him, but how can I put such a well executed diagram to waste? You did mention once that you don’t get enough Sankey Diagrams 🙂


Haven’t seen many Sankey diagrams dealing with urban metabolisms. So I was happy to stumble across this one for Paris, France on Nels’ blog.

Grey and one color seems to be en vogue for Sankey diagrams these days… 😉