From my collection of Sankey diagrams here are three very similar samples depicting energy flows in a building. All three are from Germany (did I mention that more than half of the Sankey diagrams seem to be from Germany or Austria?).

These are all very simple Sankey diagrams. This first one is a hand-drawn goodie from the times when reports were still done with a typewriter. It shows use of fuel oil (‘Heizol’) in a school building, and interesting to see, the flows are given in kilograms fuel oil rather than to represent the heating value. The school building consumes 80 tonnes of fuel oil per year.

Note that flows are not to scale (arrow for equivalent of 10580 kg fuel oil annual heat loss through walls is about the same width as the one representing 31770 kg heat loss through windows). So this Sankey diagram doesn’t deserve an A…


The next building energy flow Sankey diagram shows flows in Watts (W). Not sure where I found this one. Flows again are not proportional (spot the 470 W flow and compare it to the others). Main inputs are radiation (‘Strahlung’) and electric energy. A heat pump cycling energy can be seen, so it seems that this one is maybe for a passive house.

This last one done with a Sankey diagram software hence flows are to scale in this one (although I have some doubts regarding the width of the fuel oil input arrow on the left). Flows are in kWh per year. Main fuel type is natural gas (red), some district heating (blue). Electric energy in yellow, consumed by IT, lighting, air compressors, and so on. This energy flow Sankey diagram is probably for a factory building or complex.

I will try to add the sources where I found these three diagrams. Please forgive my negligence this time.

Digging out some gems from folders on my hard disk. I found this one back in 2010 or so, but had not documented the source properly – shame on me. I just know that it is from consulting firm Motiva. Had I really forgotten to features this here on the blog?


This one is the result of an energy analysis in a company. No numbers or units given in this diagram. Fuels by type on the left (‘polttoaineet’), then from left to right bunkers/tanks (‘kattilat’), two turbines (‘turbiinit’) generating electric energy (‘sähkö’) and steam (‘höyry’).

After posting on Australian Metals Flows yesterday I realized I had never presented a Sankey diagram for energy flows in Australia.

Well, here it is. From the Government of Australia, Clean Energy Regulator, Renewable Energy Target program website comes this beauty (CC-BY license Commonwealth of Australia):


One can really say that Australia is mainly exporting its energy. Flows in Petajoule (PJ) for the year 2012/13. Older energy flow diagrams available in the Australian Atlas of Minerals, Resources and Processing Centres here.

An updated Sankey diagram for the energy flows in Europe (EU-28 countries) is available on the website of the European Environment Agency (EEA).


Copyright holder: European Environment Agency (EEA).

I have reported previously about the energy picture with data for 2012. The Sankey diagram structure is almost identical, just the values have been updated to reflect 2013 data. Minimal changes only, compare for yourself…

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.

I have presented several examples of Sankey diagrams in the field of maritime technology before (see here).

This recent article (Baldi, F., Ahlgren, F., Nguyen, T., Gabrielii, C., Andersson, K. (2015): Energy and exergy analysis of a cruise ship. In: Proceedings of ECOS 2015 – the 28th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems) confirms that “the complexity of the energy system of a [cruise] ship where the energy required by propulsion is no longer the trivial main contributor to the whole energy use thus makes this kind of ship of particular interest for the analysis of how energy is converted from its original form to its final use on board.”

The authors conduct a thorough energy and exergy analysis for a cruise ship in the Baltic Sea. The ship has different operation modes (sea-going, manoeuvring, port stay). The energy analysis “allows identifying propulsion as the main energy user (41% of the total) followed by heat (34%) and electric power (25%) generation”. Nevertheless, “it can be seen that the energy demand for auxiliary power is comparable in size to that for propulsion.”

The data for this Sankey diagrams in the annex of the paper and shows that flows are in TJ for an operation period of 11 months. Blue, yellow and green arrows depict energy use, while the orange arrows reveal heat losses to the environment.

The study continues with an exergy analysis of the ship, since it reveals more on the system inefficiencies. The exergy analysis is shown as a Grassmann diagram in the paper. This is structured similarly to the Sankey diagram above, but has dark orange arrows representing the exergy destruction. This is mainly from the Diesel engines and the oil-fired boilers.

I recommend this paper not only to naval engineers, but to everyone who wishes to get a better understanding of exergy and Grassmann diagrams. Can we consider Grassman diagrams a subset of Sankey diagrams? What do you reckon?

After many national energy flow balances, some of which I have presented here on the blog, energy flow balances on a regional level are now coming out of France.

Benoît Thévard who writes on the ‘Avenir Sans Petrol’ blog (a French version of Peak Oil) has an interesting post on ‘Un scénario de transition énergétique citoyen pour la Région Centre’ (translated: An civil energy transition scenario for the Central Region). It summarizes a report published March 2015 by VEN Virage Energie Centre-Val de Loire.

The report features two Sankey diagrams. The first on page 33 is for the actual 2009 energy flows in Centre-Val de Loire (check here to find out about this French region)

Flows are in TWh. Production of nuclear energy comes with huge losses (efficiency approx. 35%). The main consumers in the region are residential and services, followed by transport. Energy consumption in industry plays a comparably smaller role in the region. The report explains that the region is vast and not densely populated and houses are older and larger on average compared to other regions (“le territoire est vaste et peu dense et les logements sont anciens et sont plus grands”). Another report mentioned on p. 21 calls the region énergívore (a beautiful word I read for the first time).

The other Sankey diagram on page 37 shows a nuclear-free and almost fossil fuel free scenario for 2050. Overall consumption is drastically reduced (2009 energy consumption approximately 75 TWh, 2050 energy consumption scenario 32,4 TWh). The scenario relies on a diversification of energy sources with an emphasis on wind energy and biogas. The region would hardly export any energy in 2050 anymore.

Just like for the India 2031 scenario I discussed in my last post, the two Sankey diagrams shouldn’t be compared directly, since the scale is different.

The report also has clear and straight-forward explanation on how to read the diagrams (page 32). This “diagramme de Sankey se lit de la gauche vers la droite, en partant des productions régionales d’énergie primaire et des importations, sur la gauche, pour aller jusqu’au consommateur final, sur la droite. L’épaisseur des traits est proportionnelle aux flux physiques exprimés en TWh.”

I think this a remarkable piece of information for the public. And not only because it contains Sankey diagrams. It is beautifully non-academic and inspiring to read. Those of you who understand French should have a look.

I have often wondered why we don’t see more Sankey diagrams coming out of India. With a population of 1.252 billion and a solid engineering education (according to AICTE 2011/2012 report: 3495 degree-granting engineering colleges in India with an annual enrollment crossing 1.2 million, 16% of Indian students take an engineering/technology course, number of graduates from technical colleges was over 700,000 in 2011) I would have expected more.

Maybe it is just because I don’t know how to read and write in Hindi, to look for the right term. This should be Sankey diagram in Hindi (please correct me if I am wrong): sankey_diagram_hindi

Anyways, the 2006 report ‘National Energy Map for India. Technology Vision 2030* published by the Office of the Principal Scientific Adviser to the Government of India (PSA/2006/3) does have a number of Sankey diagram figures.

This one shows energy flows for India in 2001

This Sankey diagram below is for one of the different scenarios for energy generation and use in India in 2031, called the ‘High energy efficiency scenario’. The stacked bar at the left is lower, but the absolute numbers for total commercial energy supply are much higher in 2031 than in 2001 in all energy scenarios, so these diagrams mustn’t be compared directly one to another.

See the appendix A5 (pp 271-278) for more Sankey diagrams for other 2031 Indian energy scenarios.