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Emergy Simulator: new free emergy modelling software released

[ Raphaël Valyi, a student at the french engineering school Ecole Centrale Lyon ( has just released new open-source software for modeling eMergy flows called Emergy Simulator or EmSim.

'EMergy' is shorthand for embodied energy, coined by the late systems ecologist Howard T. Odum for use in his pioneering system of energy accounting. Odum used a system of graphical symbols not unlike the symbols of circuit diagram with which he created dynamic models of energy systems. Through creating and running these models on computer he gained insights into the patterns present across ecosystems. His work was, amongst other things, used to model the famous Biosphere2 project.

Odum foresaw the coming energy peak, and released a book, The Prosperous Way Down in 2000, just two years before he died, outlining some of his recomendations for the coming era of energy descent. He saw that this era would require a completely different set of managerial strategies, personal habits and ideologies.

As we enter into an age of strained energy availability, understanding and modelling how energy - and eMergy - behaves may be one of the most important and practical intellectual pursuits for both solving particular problems, and giving general insights.

This new software allows users to create their own models of dynamic eMergy systems. This could be something like a farm, digestion, or society's use of fossil fuels. Anything that involves energy flows. Until now eMergy modeling software tools have been very expensive. Now anyone can (although not without a decent bit of studying) put Odum's pioneering work into practice.

Note for JAVA programmers: Now that version 1.0 has been released, Raphaël is no longer developing the project, but is requesting that others do.

Emergy Simulator was coded at:
LEIA lab in the brazilian university Unicamp

-AF ]

About the software:

Solar emergy (direct and indirect solar energy required for a ressource) is a very pertinent data when comparing alternatives for a sustainable development. However, emergy sudies, seem to suffer of communication low standards, both limiting broad public audience and scientific interest.

Emergy studies would have much more public policy impact if improved communication standards enhance scientific peer review and concepts democratization.

Part of the answer is coming with Emergy Simulator. This new born software is an efficient graph sketcher that allow users to draw an energy diagram while providing:

* an intuitive and drag and drop interface,
* high standard graphical features
* an extensible interactive and multilingual help system.

Then the graph structure containing models and parameters is interpreted leading to:

* a pertinent and universal databank storage as an XML file,
* dynamical quantity simulations based on bond graph and dynamical systems theory,
* an emergy track summing applied either to static or dynamic energy networks,
* unlimited object oriented assembling in order to work on large complex models.

In the Brazilian lab, Emergy Simulator will be mainly used as teaching tool providing an interactive access to the dynamic models from the Computer Minimodels and Simulation Exercises Odum's handbook.

But this tool could be much more: this an opportunity to store systemic emergy data with their connectivity structure in order to properly collect the global knowledge, to develop an error estimation with stochastic simulations, to study application of Giannantoni's mathematical empower formulation...

International collaboration and further development is required to turn this multi purpose Odum's energy modeling platform always more complete. To make it easier, all the code is GNU java open source code only base on standards (Model View Component structure, Jgraph and Fractal Aid libraries) and it's being built as Concurrent Version Source on the internet. Download, learn or develop Emergy Simulator at:

Latest report here:

Editorial Notes: Download link to ECL doesn't seem to be working, but package available via Sourceforge:

What do you think? Leave a comment below.

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