Thanks for actually answering the question. I was curious, too.

This is a repo build using the PyPSA python framework. PyPSA is an open-source Python framework for optimizing modern power systems with renewable energy, storage, and multi-sector coupling.

The repo linked “seeks to complement the tools currently used in the TYNDP cycles, especially for Scenario Building (SB) and Cost-Benefit Analysis (CBA). This approach is designed to enhance transparency and lower barriers to stakeholder participation in European energy planning. Beyond Europe, the project aspires to demonstrate the viability of open-source (OS) frameworks in energy planning, encouraging broader global adoption.

To build trust in and ensure reproducibility with the new open-source toolchain, the project first focuses on replicating key figures from the 2024 TYNDP cycle, before aligning with the current 2026 TYNDP cycle. This process involves developing new features within the open-source domain to address existing gaps, integrating tools for data interoperability and dynamic visualizations, and publishing best practices to encourage the adoption of open energy models.”

Why this report is shared appears to be an application of PyPSA for others to reference and become inspired by its implementation.

Why it’s open source I think is clear from the above paragraph. Open source standards make it drastically easier to harmonise and collaborate while allowing as much engagement as possible to scrutinise the framework.

There's a very expensive process for resource planning the electrical grid that is highly modeling dependent. Most electricity grids are planned with a least cost expansion modeling approach. A small number of incumbent vendors provide expensive closed source tools to do this. There are quite a few open tools in this space, but open energy transition is building consensus around pypsa and pypsa-eur as equivalent top of class models (better in a lot of ways) to use for various IRPs.