DIETER is an open-source power sector model designed to analyze future settings with very high sharesof variable renewable energy sources. It minimizes overall system costs, including fixed and variablecosts of various generation, flexibility and sector coupling options. Here we introduce DIETERpy thatbuilds on the existing model version, written in the General Algebraic Modeling System (GAMS),and enhances it with a Python framework. This combines the flexibility of Python regarding preandpost-processing of data with a straightforward algebraic formulation in GAMS and the use ofefficient solvers. DIETERpy also offers a browser-based graphical user interface. The new framework isdesigned to be easily accessible as it enables users to run the model, alter its configuration, and definenumerous scenarios without a deeper knowledge of GAMS. Code, data, and manuals are available inpublic repositories under permissive licenses for transparency and reproducibility.
Keywords: Power sector modeling, Open-source modeling, GAMS, Python, Energy storage, Flexibility options, Sector coupling, Renewable energy integration