ETEM is developed by ORDECSYS and it belongs to the MARKAL and TIMES model family. It is implemented in a free algebraic modelling language (GMPL, part of GLPK), so it can be freely downloaded and solved [1]. A web interface is currently being developed to facilitate online training and more information is available on the tool’s website [2, 3].

ETEM, for Energy Technology Environment Model, is a bottom-up model that finds optimal energetical and technological decisions taking in account the energy needs of a region/a metropolitan. The model aims at finding energy policy with minimal cost, investing in equipment (new technology), production capacity (installed technology) and import/export of primary energy. The model permits to analyse the impact of energy and environment policy, measure emissions due to the energy system with or without strong constraint on the emissions. ETEM is dedicated to local modelling such as a small country, a part of a country, or a metropolitan. ETEM has been developed to provide the following features:

  • Flexible representation of any energy system.
  • Ready to be integrated in a coupling framework with a chemical model (for instance an air quality model), an economic model (computable general equilibrium model),
  • The model has been developed to be modular and then accept easily new features.

An advantage of ETEM is that it is compatible with DET2STO, another tool which can automatically formulate the deterministic equivalent of a stochastic programming problem. A number of additional updates are currently being developed in ETEM including:

  • Robust Optimization (Ordecsys is specialized in optimization under uncertainty)  (ETEM-R)
  • Adaptation Policy options (ETEM-A)
  • Smart Grids management (ETEM-SG)

ETEM has already been used for Luxembourg [4], Cantons of Geneva and Basel-Bern-Zurich (Switzerland), Grenoble Metropolitan and Midi-Pyrénées region (France). Other projects have been submitted for local applications in the UK, Romania, Switzerland, and France.


  1. ORDECSYS Applications. Available from: [accessed 16 March 2012].
  2. ORDECSYS: Operations Research Decisions and Systems. Available from:[accessed 16 March 2012].
  3. Drouet L, Thénié J. An Energy-Technology-Environment Model to Assess Urban Sustainable Development Policies: Reference Manual. ORDECSYS, 2009. Available from:
  4. CRP Henri Tudor. Luxembourg Energy Air Quality Model. Available from: [accessed 16 March 2012].