MESSAGEix is a versatile, open-source, dynamic systems-optimization model. It was developed for strategic energy planning and integrated assessment of energy-engineering-economy-environment systems (E4). The framework includes the possibility for integration with the general-economy MACRO model to incorporate the feedback from price changes on demand for commodities or energy services. The mathematical formulation is based on the MESSAGE Integrated Assessment model developed at IIASA since the 1980s.

The MESSAGEix and MACRO models are implemented in GAMS. This repository contains the GAMS code and a number of tutorials and examples using stylized national energy system models.

The repository includes, as a git-submodule, the interface to the ix modeling platform (ixmp), a modeling "data warehouse" for integrated and cross-cutting scenario analysis.

Copyright 2018 IIASA Energy Program

The MESSAGEix framework is licensed under the Apache License, Version 2.0 (the "License"); you may not use the files in this repository except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0.

Please refer to the NOTICE for details and user guidelines.

A documentation of the MESSAGEix framework, including the complete mathematical formulation and associated files, is automatically created from mark-up comments in the GAMS code and the R/Python packages. The online documentation is synchronyzed with the contents of the master branch of the repository www.github.com/iiasa/message_ix.

Please cite the following manuscript when using the MESSAGEix framework and/or the ix modeling platform for scientific publications or technical reports:

Daniel Huppmann, Matthew Gidden, Oliver Fricko, Peter Kolp, Clara Orthofer, Michael Pimmer, Adriano Vinca, Alessio Mastrucci, Keywan Riahi, and Volker Krey. "The |MESSAGEix| Integrated Assessment Model and the ix modeling platform". 2018, submitted. Electronic pre-print available at pure.iiasa.ac.at/15157/.

Please follow the installation instructions of the ixmp package, which is included as a submodule to this repository. Instead of forking and cloning the GitHub repository iiasa/ixmp, please fork and clone the repository iiasa/message_ix.