The below Sankey diagrams both show wood biomass flows for Finland for the year 2013.

The first one was published in the report VTT Technology 237 ‘Sustainability of forest energy in Northern Europe’ by researchers from VTT Technical Research Centre of Finland and Natural Resources Institute Finland (Luke).


Authors of this figure are Eija Alakangas and Janne Keränen. The diagram is oriented top-to-bottom and shows how the 104.4 Mm³ of round wood that grew in Finnish woods in 2013 were used. Basically there are two (three) main pathways, with a lot of arrows branching out to depict certain uses. 38.3 Mm³ of round wood was used in pulp industry, 26.2 Mm³ in the mechanical wood industry. Another 9.5 Mm³ of wood is used directly for energy generation.

The second Sankey diagram seems to be a remake of the above. It was published in a VTT Research Report on ‘Cascading use of wood in Finland – with comparison to selected EU countries’ by Laura Sokka, Kati Koponen, Janne T. Keränen.


Here the overall orientation is left-left-to right. The color scheme seems similar. There are some minor differences in the energy use part (orange and dark red arrows).

The first diagram has some images and comes across a little more playful than the second one. Although they depict the same data, I perceive them quite differently.
Is it due to the scaling or the vertical vs. horizontal orientation? Let me know your impression in the comments please.

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 feature 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’).

Indmeas, an engineering firm based in Espoo, Finland, provides a tool for on-line efficiency calculation and optimizing plant operation. Their data can be visualized using Sankey diagrams.

Small, but nice. Unfortunately neither units nor quantities in this schematic sample pic I took from their website.

Motiva is a state owned limited company from Finland offering energy efficiency analysis and energy audit for companies. Motiva also developed audit guidelines and models, and engages in training and authorisation of the energy auditors.

In their energy audit reports, they always include a Sankey diagram in the very first chapter. Here is an example:

Other consulting companies, such as Pöyry (not sure how to pronounce this) haven taken on their approach and are also producing Motiva style Sankey

Both Sankey diagrams designed in PowerPoint. Not bad at all, but probably quite a time-consuming task.

I have posted several Sankey diagrams depicting the energy flows of countries. At least California and West Virginia have published state energy flow Sankey diagrams. I was quite excited to discover the two metropolitan energy flow Sankey diagrams shown below in this publication. They are for Toronto and Helsinki and show energy flows in 1988 in these communities.

The two diagrams show energy consumption and use in Toronto (above) and Helsinki (below). Even though the absolute figures in GWh are given, one shouldn’t directly compare them. A per capita basis would be fairer (Toronto had a population of 2.5 mio in 2006, more than 5 mio. in the metro area, while Helsinki had 580.000 inhabitants in 2008 in the city, 1.3 mio in the greater Helsinki area — Toronto is today 4.5 times larger than Helsinki). Both are “cold-climate municipalities”.

The publication calculates a ‘community energy efficiency’ of 50% for Toronto and 68% for Helsinki. “A comparison of the two municipalities reveals that Helsinki significantly improved its efficiency by using the waste heat that is produced by local coal power plants to warm 90% of the buildings and homes in Helsinki. Further analysis has demonstrated that Helsinki’s energy system was able to achieve its overall level of 68% efficiency because the city’s compact land-use pattern made investments in energy-saving infrastructure, such as district heating and public transit, economically viable.”

Does anybody know other metropolitan energy flow studies? I am aware of research activities in the field of urban material flow accounts or urban metabolism (e.g. Lisbon) but have to check whether they show Sankey diagrams in their publications.