Too many colors in the Sankey diagrams posted recently?

Here are two unicolor ones from the Exergy Design Joint Research Lab at Osaka University in Japan. Not that I understand much, but apparently the one at the top is for a gas engine system.

No absolute values given, so just a schematic representation of the flows.

From what seems to be a 1998 abstract on retrofitting the main engine of the Japanese vessel Fukaemaru come these two Sankey diagrams. Found this on the website of the Kobe University Martime Faculty. Both nice plain black&white.

The first one shows energy efficiency of the original gas turbine equipped machine room. The base seems to be 100% energy (the label actually says ‘fuel exergy’) and the useful energy (arrow going straight up, labeled 出力) is 15.48% only. Losses branch out as arrows to the left and to the right.

The other Sankey diagram shows the energy flows for a diesel powered main engine. Efficiency is up to 37.38%

Read the full abstract here (in Japanese).

On a side note: funny to see that in the description of the figure at the bottom the author actually turned “Sankey Diagram” into a “Keysan Diagram”…

Found the two Sankey diagrams on the website of the Exergy Design Joint Research Lab of Osaka University in Japan. The diagrams are for enthalpy and exergy in a Solid Oxide Fuel Cell (SOFC). Can’t fully understand what it means, but both are simple breakout Sankey diagrams that could also be presented as a pie chart.

The first one is titled “Enthalpy Sankey Diagram”:

The second one is a “Exergy Sankey Diagram”:

Anybody care to explain more?
Looking at the choice of color one could be led to believe that enthalpy is female, while exergy is male.

Some of you might have noticed that I tend to get somewhat excited when I discover Sankey diagrams in other languages.

Here is one I dug out on this webpage of the Tsuji Labs at Osaka University in Japan, and it has the honor to be the first one presented on this blog in Japanese!

The diagram shows the “energy flows” (エネルギーフロー) as relative values for the year 1993 only. On the left side we can see that more than 80% of the energy consumed in Japan were produced from imported fuels (輸入), while only 17.8% came from domestic production (国内生産). The quantities are broken down into the different types of fuels, such as crude oil (原油, 46,1%) , natural gas (天然ガス, 10,5%) or hard coal (石炭, 16,4%). The right side of the diagram shows the consumption sectors, with industry (31%), residential (16,9%) and transport (15,6%).

Losses are at 29% which seems relatively low, if you compare to similar Sankey diagrams from the U.S. But then I am not sure if they accounted for the losses in the same way for this diagram.

There are these two other similar Sankey diagram thumbnails on that site, and my guess is that they represent different energy scenarios, considering renewable energy sources, as an option to reduce dependency from imports. Maybe someone who can read and understand more Japanese than I do wants to comment?

The below Sankey diagram of the ‘Material Flows of Japan in the FY 2000′ has been published by the Japanese Ministry of Environment (環境大臣) and has been reproduced in a number of publications and presentations (sample PPT). Similar charts, representing the inputs into the Japanese economy and the outputs are available for subsequent years.

When I copied the values of the Sankey diagram and re-designed it (see pic 1 below), it quickly became obvious that the inputs (2130 Mio. tons) don’t match the Outputs (2386 Mio. tons). After some research I finally detected the reason for the mismatch in a footnote to the diagram in a press release by the ministry. It said that, “due to intake of moisture, etc., total output shall be larger than total material input.” This footnote might have been dropped unintentionally when using the diagram in other publications. I wouldn’t really call this “lying” (as the title of the post implies), but maybe negligence. I wonder if anyboy doubted the numbers when looking at the diagram?

In the second diagram below I adjusted this difference of 256 Mio. tons on the input side.


Another rather surprising thing in this Sankey diagram is the fact that the domestic food consumption within Japan (127 Mio. tons/year in 2000) was almost as high as the total quantity of material being exported (132 Mio. tons). Taking into account, for example, the number of cars being exported from Japan, and their weight, this sounds a little unlikely. However, I think that many of the produced goods might be hidden in the “Net Addition to Stock”.

And for the readers who study Japanese … Sankey diagram : サンキーダイアグラム