Download high res version of the Sankey diagram (large PDF) here.

This was prepared by Eric Shuster and is an update to the Sankey diagrams published annually by LLNL. It has the energy carriers on the left, energy conversion in the middle, and energy use sectors on the right. Primary energy consumption in the U.S. in 2010 is estimated to have amounted to 98 quads (quadrillion BTUs).

“NETL energy analysts have produced for the public a set of Sankey diagrams based on data obtained from the Annual Energy Review 2010 recently released by the U.S. Energy Information Administration. Graphically representing both quantity and direction, the diagrams place in perspective the relative contributions of major domestic energy sources as well as the flow of fossil fuels around the world.

The “Estimated U.S. Energy Use in 2010″ flow diagram shows the quantity of fuels used to drive each of the sectors in the United States. Overall, 83 percent of the primary energy consumed in the U.S. is from fossil fuels and downstream, due to conversion efficiencies, 89 percent of the total energy delivered to the end-used sectors is derived from fossil fuels.”

The news item also has a link to another presentation ny NETL featuring global coal and gas related flows as Sankey diagrams. These are interesting as will and I will present them here in the near future.

The Sankey diagram doesn’t sport the energy unit, but the text comment says:

The 2007 energy balance of Urumqi shows that about 541 PJ of primary energy was consumed in the city, accounting for 28% of the Xinjiang total (1,927 PJ). Urumqi used 25% of Xinjiang’s coal, 50% of its oil, 12% of its natural gas, and 4% of its renewable energy, much of it in heavy industry. This results in high energy related per-capita CO2 emissions of 22 tonnes. In 2007, the city consumed 14.7 million tonnes of coal (approximately 51% of its primary energy supply) whereby 30% of the coal consumption was used for the heating of buildings.

Click here to visit web page and start exploring…

Flows are in quadrillion BTUs or ‘quads’. The footnote reads:

Hydro, wind, and solar electricity inputs are expressed using fossil-fuel plants’ heat rate to more easily account for differences between the conversion efficiency of renewables and the fuel utilization for combustion- and nuclear-driven systems. This enables hydro, wind, and solar to be counted on a similar basis as coal, natural gas, and oil. For this reason, the sum of the inputs for electricity differs slightly from the displayed total electricity output. Distributed electricity represents only retail electricity sales and does not include self-generation. The efficiency of electricity production is calculated as the total retail electricity delivered divided by the primary energy input into electricity generation. End use efficiency is estimated as 80% for residential, commercial, and industrial sectors, and as 25% for the transportation sector.

Nice graphics and a good idea to convey “What You Need To Know About Energy”.

European (EU-27) Energy Usage:

European (EU-27) Energy Usage (renewable energy sources only):

These two images were posted by Herman B. (apparently linked somehow to the European Comission) in reply to an inquiry by Andrew D. I don’t know the original source or publication. Flows are in petajoule (PJ) for the year 2006.

In my optinion they could do without the background image and the photos, but nevertheless, these are fine Sankey diagram examples.

Craig writes:

“here’s a Sankey diagram of the energy balance in an industrial compressed air system. The factory is situated in Ireland (not too far from Co. Tipperary!) [Note from Phineas: this is where Cpt. Sankey was born]. The work is detailed in: Eret, P., C. Harris, G. O’Donnell & C. Meskell, A practical approach to investigating energy consumption of industrial compressed air systems. Proceedings of the Institution of Mechanical Engineers, Part A (Journal of Power and Energy), 2011. DOI: 10.1177/0957650911423173″

A nice, simple, clear diagram. Thank you. If other readers have Sankey diagrams to share, please send them to blog@sankey-diagrams.com

Page 22 of the PowerPoint has the following Sankey diagram:

The pic isn’t very clear, and it is difficult to see any detail. The overall energy consumption of the Kundl site comes in from the left (962,5 GWh in 2009). It is broken down to electric energy, energy from fossil fuels and energy from biomass (Note: I was wondering about the latter, but this is explained on page 6 that this is “feed for fermentation, solvents, … “). The streams are further broken down by use area. At the right side the flows join again to visualize useful energy and energy losses.

Good to see that large industries are using Sankey diagrams as an important element of their integrated energy management…

The diagram is for predicted energy intensity for buildings. An Excel template is provided that allows entering the data. You can use this with the free trial version of e!Sankey (registering required). All elements of the diagram and the entry sheet is explained in detail by Premnath. In regard to the unit (KBtu per square foot per year) he says:

Last but not least, kBtu/sf/yr is becoming the universal (US) unit of communicating building energy consumption. This unit is called the EUI – Energy Use Intensity and since it is a simulation of how your building will perform, it is called PEUI – Predicted Energy Use Intenisty.

Good stuff, Premnath! Thanks for making this available to everyone.

Note November 2011: Also look at Premnath’s Energy Story here.

The study concludes that it would be advisable to feed the liquid co-products to an anaerobic digester to produce methane. A power generator can use this fuel to meet the electricity demand of the distillery, the surplus could be fed to the grid. Exhaust gases from the generator can be utilised by a waste heat boiler to offset the steam requirements of the stills. This would result in an annual economic benefit of £178,450 and a payback period of 5 years.

The Sankey diagram shows electric energy in MWh, co-products in tons per year, and biomass in cubic metres. Hence, these flows must not be compared to each other. I am unsure about the red arrow from the steam boiler to the distillery, which is labelled ’18,841 MWh’ as it doesn’t seem to be to scale with the other energy flows.

Anyways. I like this one. Here’s tae us, wha’s like us? Damn few, and they’re a’ deid.

The draft standard ISO 13579-1 talks about energy balance (‘bilan énergétique’). Part 4.2 shows a sample Sankey diagram and explains that this is a tool that allows to represent the in and out flows of energy (‘outil permettant de représenter le flux d’entrée et de sortie de l’énergie’). In section 9 f on reporting the draft standard recommends that the report shall include a Sankey diagram (‘Il convient que le rapport de mesure du bilan énergétique contienne … Diagrammes de Sankey.’).

Didn’t have the original English version at hand, so I hope this is pretty much what it says in French.

Anyone aware of other ISO standards that mention Sankey diagrams?

The Sankey diagam has a nice mouse over effect, that let’s the user explore the stream as they are highlighted in different colors. The nodes show the contribution from different carriers. Additional information is available when positioning the mouse over the orange bullets. This makes the diagram fun to explore…

In this image the lost energy is highlighted in red.

In the above screenshot the energy flows based on petroleum are shown in brown color, all other flows in light grey.

These are only two static screenshots, please go over to the Bloomberg site to see more.

The report has numerous other Sankey diagrams like this one, similarly structured. They show energy use of coal, petroleum, natural gas, and renewables.

Below is the one on petroleum flows in 2009 in millio tons. A lower threshold has been introduced, so that small quantities don’t fall below a minimum width (see, for example, the flow of 0.7 mio tons to “Rail”, compared to the one of 4.9 mio tons to “Industry”, which would in principal be 7 times wider if it was to scale.

Nice and colorful!

I have presented several similar Sankey diagrams here on the blog for different countries (see Spain, Italy or Austria or browse the tag ‘energy’)

This is a neatly structured and nicely designed example of a energy flow Sankey diagram that could serve as a role model. Primary energy broken down by energy carrier is on the left. Conversion steps are shown in the second tier, as two alternative breakdowns (direct fuel use/electricity generation and motion/heat/other). The line where these two tiers touch don’t always have direct connections, but the overall arrow magnitide matches. The next tier (passive systems) is broken down into vehicle, factory and building. The final services on the right side distinguishes eight different energy use fields.

Flows are in Exajoules (10E18 joules) and values are for the year 2005.

“Better monitoring of process variables, improvement in the operating point (or range) of the process, installation of heat recovery systems (e.g. at heat exchangers), use of heat pumps and replacement of high energy streams (steam) with waste heat streams. Most of these techniques are standard recipes which are readily available in the market. However they are designed without giving any consideration to the specific aspects of a manufacturing facility and also provide no quantitative evidence of the potential benefits. “

This is why they came up with a mass and energy balance model and are using the following Sankey diagram to visualize where energy could be recovered.

Flows are labeled as enthalpy flows, showing the changes in thermodynamic (heat) energy at each process step, hence losses. The Sankey diagram is for a balance period of six hours. No absolute figures are given. Several heat exchangers are installed along the wet section of the paper machine. In the drying section, a large part of the energy is lost as steam/humid air.

The annual report 2010 includes three Sankey diagrams, two of which are shown below. The first Sankey diagram (p. 16 of the report) has the typical pattern of a ‘national energy consumption, conversion and use’ diagram, similar to the ones presented here on the blog several times already for other countries.

The flows from the left show energy sources, the nodes on the right are the use sectors. A nice feature here is that the node heights are adapted to the magnitude of the Sankey arrow, so that the largest energy consumption can immediately be seen. Flows are in in Exajoule (1 EJ = 1000 Petajoule = 10E18 J). The total primary energy consumption in Spain in 2009 was 5.86 EJ (4.95 EJ of which are from imported fuels). Also shown next to the absolute quantities is the relative share of each flow in percent, and the change in comparison to the previous year.

The second Sankey diagram (p.22) is what I would call a value stream Sankey diagram.

This is interesting as the market price for the fuels, as well as for converted energy is used as a weighting factor, so that each Sankey arrow shows the value of the energy flow in millions of Euro. At some nodes you can see that a smaller arrow enters, and a wider arrow leaves: These are the conversion processes where value is added (or energy gets more expensive). This is a compelling concept for a Sankey diagram (another similar example is here), one that somehow could make Sankey diagrams more interesting for economists or controllers, rather than considering them exclusively in the engineering domain.

The third diagram (not shown here, p. 19 in the report) shows the embodied carbon or the greenhouse gas emissions related to the different fuels, broken down by fuel and sector of energy consumption. The embodied carbon in the energy carriers were roughly 285 Mtons in 2009. The Sankey arrows for renewable energy sources as well as for Uranium are not present in the third diagram.

Me gustan mucho estas tres diagramas de Sankey! Merecen elogío.