Month: November 2010

Samples

Pimp my nitrogen Sankey

Below is an example of a Sankey diagram showing a nitrogen metabolism. The original diagram is from a Japanese publication (‘White Paper on Quality of the Environment in Japan 1994’), even though the diagram represents nitrogen loads (in 1000 tons N) in the Netherlands in 1990.

nitrogen_flows_netherlands_1990

A pimped version of this diagram can be found in the e!Sankey download gallery. I don’t like the color very much, but the overall aspect of the diagram is much better than in the b/w version, I think.

netherlands_nitrogen_flows

They seemed to have struggled with inconsistencies in the original diagram, as an annotation suggests. Also the denitrification due to accumulation in the bottom sediment, or nitrogen ending up in durable goods (shown in black in the original) are not represented in the remake. For the rest it pretty much sticks to the original.

Thinking about a new tag “pimp my Sankey”…

Methodology, Samples

Superimposed Sankey diagrams

The below Sankey diagram from the JS Systems homepage tries to show the differences between a normal Otto engine and the “JS Motor”. The prototype JS rotation motor, from what I grasp, has different compression and expansion parameters and could prove to be twice as efficient.

jrc_motor_sankey

To show the difference in efficiency, two Sankey diagrams have been superimposed. The diagram with the grey outline is for the Otto engine, the one with the red outline is for the JS engine. The diagram shows energy losses branching off to the right (e.g. thermodynamic losses 17% in a typical Otto engine, 13% only in the JS motor). Useful energy is represented by the flow to the top.

I am not endorsing this motor, nor have I seen it work. But I like the idea of presenting a comparison in one Sankey diagram instead of two separate Sankey diagrams.

Also, please check out this previous blog post on Sankey diagram overlay.