Losses in Fruit Production

Food loss or wastage has been a topic a previous posts here on the Sankey diagrams blog before (see here or here).

Here is another Sankey diagram from the dissertation ‘Environmental assessment of Catalan fruit production focused on carbon and water footprint’ by Elisabet Vinyes i Guix (p. 73). It visualizes losses in the production chain for apples and peaches in Catalunya.


For each kg of fruit arriving on the market (or at the point of sales), some 1.21 kgs of fruit are being cultivated. Losses occur in the farming process itself as well as along the retail system. Of the 1 kg fruit purchased by the consumer, only 83% is actually eaten. 17% turns into waste.

Spelling Variants Distribution

Interesting and fun example of data analysis and visualization of distributions using tree-like Sankey diagrams: The Pudding (“a digital publication that explains ideas debated in culture with visual essays”) has a post on the Gyllenhaal Experiment.

How do people spell the more or less difficult names of celebrities? Using occurrences of these names on reddit, they counted the spelling variants, then displayed them in this Sankey-style distribution diagram.

Here is one for the actor Zach Galifianakis (via TNW):


You can read this figure like branching pathways for alternative spellings. The blue path is the correct spelling. All people get the first three letters ‘Gal-‘ correct, but then they go on and spell it differently. Very quickly you get a great number of variations (which I am sure Galifianakis who has Greek roots is used to…).

Only the two main options (‘Galifinakis’ and the correct one, Galifianakis) show the absolute values, and the widths of the bands are apparently to scale. The other options with less hits only show two default widths. I also noted that the further downstream on a path, spelling variants, which would cause further branches, have been ignored.

I wanted to do one myself, and checked the underlying data. Turns out there are 2.632 spelling variants (many of which only have one count), so showing all of them in a tree-like diagram does not make much sense. One would have to either choose the 10 or 20 most common misspellings, and then decide to sum up the rest under “other” or drop them for good.


And here is what it looks like based on the top 10 spelling variants (n=15848). Flows are to scale and absolute numbers have been added. Less than 16% from this group spell the author’s name correctly, the most popular spelling variant collects more than 40% (click image to enlarge)


Maybe time for Zach to consider a name change 😉

European Copper Streams 2012

After all these colorful Sankey diagrams, here is something soothing for your eyes.

This b/w Sankey diagram shows European copper streams in 2012. It is taken from the 2017 dissertation by Simon Gloser-Chahoud of Technical University Clausthal in Germany with the woooh title ‘Quantitative Analyse der Kritikalität mineralischer und metallischer Rohstoffe unter Verwendung eines systemdynamischen Modell-Ansatzes’ (‘Quantitative analysis of the criticality of mineral and metallic raw materials using a system-dynamic model approach’ …thanks Google Translate!).

Flows are in kt. The dotted line references the geographical boundary of the EU-27 states. We can see that 1.100 kt copper concentrate was imported and 830 kt came from mines in Europe. Import and export of finished products containing copper is almost balanced. The overall addition of copper to the European stock (estimated at 90.000 kt) was at 3.200 kt. Copper in waste streams leaving this stock amounted to 2.500 kt, of which 1.750 kt were fed back into the copper production.

LatAm BEN – Colombia

Colombia is next in my mini-series on National Energy Balances (Balance Energético Nacional, BEN) of countries in South and Central America.

Searching for an energy flow chart for Colombia brought up a lot of data and publications by UPME (Unidad de Planeación Minero Energético), an agency of the Ministerio de Minas y Energía (MinMinas). However, finding an actual energy flow chart turned out to be more difficult. I finally found one for 2012 in a presentation ‘Potencial energético colombiano para la generación de energía y su óptimo aprovechamiento’ by UPME on a U.S. National Institute of Standards (NIST) website.

With Colombia being an energy exporter, they seem to have been facing the same problems as Bolivia and Ecuador when drawing the Sankey diagram: The comparatively much larger energy export quantity kind of dwarfed the other flows of the Sankey diagram. Hence, in the same presentation, they excluded the export stream and focused on the domestic energy flows.

Flows are in terajoules (TJ) for the year 2012 in both diagrams. The scale of the two diagrams is not the same, so they must not be compared to each other. What has been reduced to tiny streams and hairlines by the massive export flow in the first diagram, received more weight in the domestic energy flow diagram.

A good solution to a general issue when handling flows with huge differences in the same Sankey diagram.

UK Iron and Steel Industry Energy Flows

A hidden gem (or should I say an easter egg) buried deep in an old report ‘ENERGY TRENDS. June 2011’ published by the Energy Statistics Team of the UK Department of Energy and Climate Change (DECC).

This is from page 47 of the report. Flows are in TWh. The flow chart is explained on pages 44 to 46, and the actual data for each of the numbered flows can be verified in the table on page 45.

Embodied Emissions of Products in the EU

Embodied emissions (similar to embodied energy) is an interesting perspective on the environmental impact of products we use. It takes into account the full life-cycle of the product and aggregates the emissions produced from raw material extraction, from the actual manufacturing, from the transports along the supply chain, and from the disposal of the product after use.

In many cases ’emissions’ is reduced to greenhouse gas emissions (GHGs) and the impact on climate change caused along the product’s life cycle. In this case we could colloquially also call it the ‘carbon rucksack’ of the product.

Kate Scott from the Sustainability Research Institute, School of Earth and Environment, University of Leeds (UK) in her article ‘Extending European energy efficiency standards to include material use: an analysis’ suggests the European Union should – in addition to its energy efficiency policies – add consideration of material efficiency of products to their climate change strategy. GHGs are considered a lead indicator for material efficiency, as “material-intensive manufactured products … offer significant scope for emissions reductions along product supply chains.

This Sankey diagram of supply chain emissions associated with global product flows of the EU is presented.


Source: Kate Scott, Katy Roelich, Anne Owen & John Barrett (2018) Extending European energy efficiency standards to include material use: an analysis, Climate Policy, 18:5, 627-641, DOI: 10.1080/14693062.2017.1333949 distributed under Creative Commons Attribution License.

The diagram doesn’t show much detail as to the individual stream and relies heavily on color coding. Only group sums are shown. Data is for the year 2007. Flows are in Mt (megatonnes) CO2-equivalents embodied as emissions in the products.

“Production emissions in the EU in 2007 were 5,213 MtCO2e, with the width of each flow on the left-hand side of Figure 1 representing production emissions by sector, the conventional accounting approach. In the same year, the EU’s consumption-based emissions, the right-hand side of Figure 1, were 39% higher, at 7,256 Mt due to the EU’s trade balance. Emissions embodied in EU imports were 2,847 Mt and emissions embodied in their exports were 804 Mt, meaning that the EU is a net importer of 2,043 MtCO2e (imports–exports).”

The black streams from the top represent embodied GHG emissions from raw materials, finished products or product components imported into the EU.

Read the full article here.

LatAm BEN – Ecuador

Continuing my mini-series on Sankey diagrams showing energy balances of Latin American countries. After my recent post on the Balance Energetico Nacional (BEN) of Bolivia the neighbouring Peru would be next. However, I have presented a Sankey diagram on energy flows in Peru on this blog before. So today, here is the BEN for Ecuador. It is published every year by the Ministerio Coordinador de Sectores Estratégicos.


Data is for 2016. The unit of flows is ‘kbep’ (kilo barrels of oil equivalents / miles de barriles equivalentes de petróleo). The appearance is very similar to the BEN Bolivia I showed here.

Again the flows are not to scale, which is a pity. Smaller flow quantities (in the range of 0 to 1000 kbep) are shown as arrows with a minimum width, which is fair, because otherwise we wouldn’t see much more than a hairline for ‘Solar’ or ‘Eólica’. However, if you look at the light grey flow of 17,533 kbep derivates exports branching out after the refineries node, it has the same width as the arrow representing 3,024 kbep of own use (consumo própio) – although it should be 5 times wider. The orange arrow depicting 4,433 kbep of natural gas on the other hand is wider than the one 17,533 kbep derivates exports…

I really like the graphical aspects of the Sankey diagram, and I admire the effort made here to come up with an annual Balance Energetico Nacional. In my opinion, not showing the flows to scale thwarts the whole effort, and makes using this diagram type superfluous. I know that doing such a Sankey diagram to scale is sometimes challenging, in particular when there is a very large dominating flow (like here the 139,046 kbep petroleum exports), but nevertheless, the message you are otherwise conveying with the figure is simply misleading.

Just as for Bolivia I will again have to draw this one myself …