Month: July 2012

Summer Time Sankey: Ice, ice, baby!

The charchitecture blog is run by a “third year architecture student in Bill Sherman’s Building, Sites and Systems course”. The below Sankey diagrams are from a November 2011 post and covers the topic of refrigeration.

The first Sankey diagram depicts a cross section of an ice rink and shows a breakdown of the energy use in an inefficient ice-rink.

In the second Sankey diagram an efficient and an inefficient ice-rink are compared.

Sankey arrows represent relative shares in percent, not absolute values. Hence in the second figure the height of the stacked Sankey flows (100%) is the same for the inefficient as for the efficient ice-rink. I think that a direct comparison of the energy consumption is not intended here, but only the different distributions.

The original post has more basic information on refrigerations and explains technologies that can be used to save energy.

Now that’s cool… my summer time post for you.

Freshwater Consumption and Distribution

The below distribution diagram (aka ‘Spagehetti diagram’) was presented on flowing data. It shows the top 10 nations in regard to freshwater consumption on the left, and the sectors where water is consumed on the right (column “Use”).

The author of the diagram is Jen Christiansen and it was originally published in a Scientific American article by Mark Fischetti.

The unit is million cubic metres per year. Only the absolute water consumption per nation is given, no values for the water consuming activities. Many of the commentators of the post pointed out that a per capita consumption of water would give a different, a “fairer” picture.

I refrain from commenting the content of the graphic. But I like the clear layout with the bands running in parallel and nicely stacked.

FOE Diagram: Up in Smoke

Friends of Earth have published this Sankey diagram produced by ‘Information is Beautiful’ on their webpage on July 6. It shows how energy is wasted in the United Kingdom. It shows that “huge amounts of energy are wasted every day in our gas, coal and nuclear power stations” and, in fact, “over half of the energy in gas and around two thirds of the energy in nuclear and coal used to produce electricity is lost as waste heat.”

The diagram is based on data from Department of Energy and Climate Change, DUKES 2011 and Energy Saving Trust 2012. Absolute figures are given for the different sources at the top in the diagram, and for the amount of energy “left after production” (328.3 TWh). So mainly it is the (non-)efficiency of the production expressed as relative percentage figures that is shown.

One interesting thing about this energy flow Sankey is that it distinguishes between “Thermal” (yellow) and “Renewable” (green) sources of electricity. This is in contrast to the classic renewable/non-renewable split, since in this diagram biomass falls under thermal sources. Interesting.

High-res PDF with the diagram can be found here. There is also another Sankey diagram in the original PDF that shows the consumption of energy in private homes. Will show that one in a separate post some other time.

Something went wrong here…

As some of you might know, I also like to post a diagram from time to time that has, … mmmh, say …. has the potential of being improved. This one, found on the website of a German consulting firm, is such an example.


I am glad they don’t call this a Sankey diagram anywhere. Everything that could go wrong did go wrong here. The horizontal arrow segments all have the same width, probably due to the fact that the diagram was prepared by combining rectangles. The added outflows that leave vertically at the bottom are much wider than the horizontal first segment. And the outflows are not to scale when being compared among each other (check the 5% arrow commpared to the neighnouring 11% arrow that should have roughly the douuble width. OMG!

Process Heat from Solar Power

Managed to translate most from a website on process heat from solar systems installed in a brewery I had found recently. (again a Sankey diagram from a brewery!). The article sports four different Sankey diagrams for the energy flows in the brewery: one for the entire calendar year 2010, and three further ones for January (winter mode), March (transition period) and July (summer mode) of the same year. This work at Hofmühlbrauerei Eichstätt brewery was apparently supported by Technical University of Chemnitz.



Energy is obtained from three different solar collector fields with different harvest. Flows are in kWh. Energy harvest in March was 75.158 kWh, and in July went up to 132.155 kWh. A description of the whole system and photos can be seen on this page (text in German only).

There are three consumers (the three pink boxes at the right)) that each have different demands depending on the season: Indoor heating (“Raumheizung”), brewing water and domestic water pre-heating (“Brau- und Brauchwasservorwärmung” – Google Translate didn’t help me on this one…) and warm water for the bottle washing machine (“Flaschenwaschmaschine”).

While in winter most of the energy from the solar collector system is directed to indoor heating, in summer it is the opposite: since no indoor heating is needed the whole energy harvest can go to water heating for the other machines. The storage tanks also have a color scheme indicating the temperature.

Very nice! Good work!