The accelerating development of open-source energy system modelling tools in recent years has now reached the point where it opens up a credible alternative approach to closed source exclusivity. An ever increasing number of studies are demonstrating that it is possible to produce analysis of a high quality using open-source energy system models, whilst building a wider participating modelling community. This builds confidence in results by enabling more effective peer review of work and therefore more effective feedback loops. It also builds a consistent stream of new talent entering the space to ensure that energy sector analytical capacity can be retained and steadily expanded.

PyPSA-RSA is an open energy model of the South African power system that can be utilised for both operational studies and generation and transmission expansion planning studies. PyPSA-RSA is built upon the the open toolbox PyPSA for which documentation is available. The model is currently under development and has been validated for the single node (1-supply), for more information on the capability of the model please see the associated readthedocs.

This model makes use of freely available and open data which encourages the open exchange of model data developments and eases the comparison of model results. It provides a full, automated software pipeline to assemble the load-flow-ready model from the original datasets, which enables easy replacement and improvement of the individual parts.

PyPSA-RSA has been designed to conduct capacity expansion planning studies at differing spatial and temporal resolutions. Three different spatial resolutions are available in the model:

• 1-supply: A single node for the entire South Africa.
• 11-supply: 11 nodes based on the Eskom Generation Connection Capacity Assessment of the 2024 Transmission Network (GCCA – 2024) regions.
• 27-supply: 27 nodes based on Eskom 27 supply regions as per the original PyPSA-ZA model.

PyPSA-RSA can be solved for a single year, or for multiple years, with perfect foresight. Multi-horizon capacity expansion planning is compuationally intensive, and therefore the spatial resolution will typically need to be reduced to 1-supply or 11-supply depending on the number of years modelled. By defualt PyPSA-RSA uses full chronology (8760h per year), but the number of snapshots can be reduced through the use of time-series segmentation through the open-source Time Series Aggregation Module.

This project is currently maintained by Meridian Economics. Previous versions were developed within the Energy Centre at the Council for Scientific and Industrial Research (CSIR) as part of the CoNDyNet project, which is supported by the German Federal Ministry of Education and Research under grant no. 03SF0472C.

NOTE

Credits to Jonas Hörsch and Joanne Calitz who developed the original PyPSA-ZA model, Meridian Economics who extended the PyPSA-ZA model. PyPSA-RSA is relies on a number of functions from the PyPSA-Eur and PyPSA-Meets-Earth.