What happens to yard waste and biowaste in Germany? This Sankey diagram from a 2014 PowerPoint presentation titled ‘Flächendeckender Ausbau der Biotonne in Deutschland’ by Peter Krause and Rüdiger Oetjen-Dehne (u.e.c. Berlin) shows how these flows were distributed.

In 2012 there were 14.5 mio. tonnes of yard waste andd 6.6 mi. tonnes of bio waste (kitchen/food waste) were disposed of in Germany. Much of it was collected and treated or – such as in the case of yard waste – composted (7.8 mio. tonnes).

In addition to the absolute quantities the labels along the Sankey arrows show the average per inhabitant (kg/E, a).

A large potential is still in bio waste (orange-coloured arrow) being disposed of in regular household waste (“Restabfall”). Calls for separate collection of bio waste for energy recovery are being made.

Following up on my previous post on Iran’s Energy Balance, here is another Sankey diagram from p. 54 the latest edition of ‘Iran and World Energy Facts and Figures, 2012’ by the Ministry of Energy (MOE) of the Islamic Republic of Iran.

Unfortunately the overall national energy balance of Iran is not depicted in the 2012 edition of the report any more.

This Sankey diagram focuses on electric energy only. Flows are in GWh per year (in 2012). Fuel sources for electricity generation are broken down in thr first arrow. Losses branch out at the ‘pow plant’ node as a blue arrow. The generated electricity is further broken down in the vertical arrow into consuming sectors. The overall efficiency of the power plants is at approximately 34%. Note how the small arrow head peeking out to the left is not to scale, and understates the 63.6% transformation losses.

Nuclear energy is less than 1% of the overal electricity production. In 2011, the first year of production 327 GWh were produced from nuclear fuel, upping to 1847 GWh in 2012. See p. 50 of the report.

Stimulated by the media frenzy and the focus Iran gets in recent days (nuclear deal, lifting of sanctions, Iranian oil production and effects on the world market, U.S. navy boats in Iranian waters) I thought it would be wise to look at the country from my narrow Sankey diagram perspective.

Any Sankey diagrams from Iran on the web? Of course!

The Ministry of Energy (MOE) of the Islamic Republic of Iran has been publishing the Energy Balance of the country: here is the Sankey diagram for 2009. This is from p. 67 of the bilingual report ‘Iran and World Energy Facts and Figures, 2009’ available on their web page.

Flows are in Mboe (Millions of barrels of oil equivalent). Out of the total 2587 Mboe primary total energy source, the largest chunk is oil (1585 Mboe), followed by gas (866 Mboe). More than half of the petroleum is exported (blue arrow). Total final consumption is 1144 MBoe. Note that nuclear energy is not shown in this energy balance. Apparently electricity production from nuclear power plants started in 2011 only.

Flows are not always perfectly to scale in the lower range: comparatively thin arrows have been left at a minimum width it seems. At the branch-offs of some wider arrows (oil, petroleum products) the gap has been color-filled, which makes the arrow look wider than it should be. A funny hump of the mauve arrow bridging the refinery node…

I confess I admire the Perso-Arabic script.

I have two more Sankey diagrams from another Iranian report, but these are for another post … soon.

The last Sankey diagram from the maritime sector I presented in this post receievd was shared a couple of times, so here is another one from the same topic area. Sorry, but this one is a little bit blurry even in the original document.

Taken from page 8 of the 2014 report ‘Next Generation Energy Management’ by DNVGL AS (authors George Dimopoulos, Nikolaos Kakalis).

Losses branch out as dark grey arrows. From the 100% energy in fuel only 28.9% are used as propulsive thrust, some other 5.6% as on-board electricity, heat or service steam.

Many more Sankey diagrams in the same report, check out figures 9, 12, 16 and 17.

The Wikipedia article on ‘Earth’s energy balance’ has recently been updated with another figure by user ‘Cmglee’.

It shows energy “in” from solar radiation, reflection, and energy “out” as heat into space.

This is a more abstract, yet at the same time brillant and beautiful representation of the greenhouse effect figure, that appears twice in the same Wikipedia article, and that I have presented in posts some years ago (here and here). These more infographic-ish figures are all derived from the original Kiehl and Trenberth (1997) work, if I am not mistaken.

Cmglee’s visualization reminded me of a bundle of ropes suspended at two points. Ropes of different diameter, of course, as it is common in Sankey diagrams. See more of Cmglee’s artwork here.

OK, this doesn’t claim to be scientific at all. Credits for this idea go to Mariluz Congosto who did such a New Year’s Wishes Sankey Diagram in Spanish two years ago.

This time I refrain from criticism of the Sankey diagram. I could say that there are no units given for the flow quanities. Also, weight of the contributions to the four categories will in most personal cases not be equal. Love must certainly have a much fatter arrow. For some, prosperity might have more importance. Are the categories weighted properly amongst each other? Are the colors chosen appropriately? 😉

Best wishes to all readers of the blog. Have a very happy new year 2016 full of health, happiness, luck and prosperity! For a recipe use the Sankey diagram above.

Original Sankey diagram for 2014 by Mariluz Congosto with whom I share an afición:

Closing my blogging activities for this year with a simple, clear, colorful Sankey diagam. This one is shipped with the demo version of e!Sankey 4 as a sample diagram.

This is for energy flows (heat and electricity) in a hospital. Flows are in MWh per year. Natural gas is used to fire a steam boiler and two cogeneration (CHP) units. Heat is used directly for heating in hospital buildings (red arrows). Power from CHP and electricity from the grid shown as yellow arrows.

As you are aware I am constantly looking for samples of Sankey diagrams, be they good, mediocre, or … fair.

This 2009 report on fuel cell technology (‘Natural Gas – Fueled Distributed Generation Solid Oxide Fuel Cell Systems. Projection of Performance and Cost of Electricity’ prepared by J.Thijssen LLC for US Department of Energy, National Energy Technology Laboratory, and RDS under contract number 41817M2846) has two Sankey diagrams I would like to share with you. The report assesses energy efficiency, water use and CO2 emissions of the fuel cell system.

I confess I am no expert in fuel cell technology (Wikipedia basics), and I assume the technology has evolved quite a bit over the last years. So I limit myself to a description of the Sankey diagrams presented.

On page 9 figure 3-4 shows the energy balance “Sankey Diagram of the Baseline NG DG SOFC System” (NG = natural gas, DG = distributed generation, SOFC = solid oxide fuel cell). With an energy content of the natural gas input of 9.1 MW (based on the higher heating value) and an output of 5.2 MW electric energy the system has an efficiency of 57%.
We can identify three loopbacks: syngas is recovered and fed back into the process, and heat is recovered “by thermal recuperation (by preheating the cathode air and raising and superheating steam) and chemical recuperation (by reforming part of the hydrocarbons, mainly methane, in the fuel)” (p. 8). These are the red arrows.

Now here is what I don’t like about the Sankey diagram: While most of the arrows seem to be to scale, some aren’t. Losses branching out to the top are graphically exaggerated. The arrow representing thermal losses (2.5 MW) should be about half as wide as the one for 5.2 MW ‘Net Power AC’.
The heavy spikes at the head of the arrow for inverter losses and energy used for CO2 compression overemphasize the comparatively small quantities of 0.2 MW and 0.3 MW (?!). The latter arrow seems to be labeled incorrectly (30 MW instead of 0.3 MW).

The Sankey diagram for water use of the fuel cell system on page 22 also has some obvious technical flaws:

In this diagram we are looking at water flow rates in kg/s. It seems as if most of the water is in a closed loop (0.52 kg/s) in the syngas recovery. The report on page 21 explains that “[w]hile the water demand for the NGDG system is considerable, net water use for the NGDG system is minor (only about 0.15 gal/kWh or 790 gal/day […]). The steam reformer has a steam demand more than 10 times this amount (about 0.55 kg/s)”. The label of the feed arrow at the top left has a wrong label and refers to 790 gal/hour(!).

The magnitude (width of arrow) of the main loop representing a flow rate of 0.52 kg/s water in syngas recycle is not maintained especially in the curves.
The main problem however is that it is not clear at which process step water comes in or flows out. I have come to the conclusion that the arrows for inflows (increase of arrow width) and outflows/losses (decrease of arrow width) are actually missing. So if you imagine an outward arrow to the label “0.12 kg/s water consumption at SMR” and two inward arrows from “0.44 kg/s water production in stack” and “0.06 kg/s water production in burner” the Sankey diagram starts to make sense.

Will try to draw my own version of the Sankey diagram and present it here. Note that ‘SMR’ is for steam methane reforming, abbreviation not explained in the report.