PowSyBl may be scripted for a quick solution, but it can also be used as a library to write complex software for power system simulation and analysis. Using PowSyBl, developers can create applications able to perform dynamic power flow simulations and security analyses on the network, handle a variety of formats including CGMES for European data exchanges, and many other tasks.
Project Lifecycle Stage
Early Adoption
Project Special Interest Group
Grid Simulation and Modeling
PowSyBl has a completely modular design, enabling developers to extend or customize its features by providing their own plugins. Modularity is a key value of PowSyBl’s open source design.
The image below shows the PowSyBl network map service, showing the electrical grid as a network over a map of Paris:

PowSyBl provides a complete internal model of the electrical grid, complete with substations, voltage levels, AC and DC lines, two- and three- winding transformers, batteries, generators, loads, shunt and static VAR compensators, and other related equipment.
For security analyses, PowSyBl enables users to define contingencies on the network. The grid model can also be enhanced with extensions that provide complete equipment modeling, including dynamic profile, short-circuit profile, and monitoring.
PowSyBl also provides importers and exporters for several common pan-European exchange formats – ENTSO-E CIM/CGMES, UCTE-DEF, and more.
PowSyBl as a library provides several APIs for power system simulation and analysis, including power flow computation, security analysis, remedial action simulation, sensitivity analysis, time domain simulation, and other simulations. These simulations can run either on a personal computer or on a server. The separation of the simulation API from the implementations allows developers to provide their own implementations if necessary, making the framework very flexible.
PowSyBl is also available as a command line tool for quick-shot modelling and simulation. PowSyBl scripts may be written and executed thanks to the dedicated Domain Specific Language (DSL) code included in the project.
All features of PowSyBl are exposed as web services to make it easy to build web-based applications on top of the framework.
Project Features
PowSyBl includes many features:
-
Grid data model, described with Java classes
-
Extension capability and modular architecture with plugins
-
Data management system
-
Importers and exporters for several formats (CIM-CGMES, UCTE, and others)
-
APIs to various computation modules (load-flow, security analysis, short-circuit computation, sensitivity computation, optimizers, AMPL)
-
Visualization features: single-line diagrams, network-area diagrams, map-viewer, Jupyter widgets
-
Distribution framework for HPC (tested on a 10,000-core platform)
-
Scripting
PowSyBl as a library provides several APIs for power system simulations and analyses, including:
- Power flow computations
- Security analyses
- Remedial action simulations
- Short circuits computations
- Sensitivity computations
- Time domain simulations
These simulations can run on a supercomputer – this has been tested using the CORDIS iTesla project with the Curie supercomputer.
PowSyBl is written in Java but is also available to Python users through Pypowsybl, the Python binding and to Julia users through powsybl.jl.
PowSyBl is licensed under the Mozilla Public License 2.0. PowSyBl was initiated by RTE and contributed to LF Energy in 2019.
PowSyBl Case Studies
Related Posts
PowSyBl Release Train Complete
PowSyBl has completed its latest release train, bringing together new versions across the repositories that work together within the platform. Together, these releases introduce updates spanning network modelling, load flow, sensitivity analysis, remedial action optimisation, ENTSO-E functionality, dynamic simulation, and diagrams. The release of powsybl-dependencies 2026.1.0 concludes the train. The table below provides repository and…
Recap of the 2026 PowSyBl Bootcamp: A path towards a strong community
PowSyBl (Power System Blocks) was born inside RTE, the French transmission system operator, from a very practical need: power system studies were becoming more complex, more numerous, and more tightly integrated with European processes than ever before. It led to designing a modular, extensible software library that could serve as a common foundation for many…
LF Energy Welcomes New Members, Launches Three Projects, and Advances Open Source Grid Technology Across the Portfolio
LF Energy welcomes new members AZX, EcoPhi, and Empa; launches the AINETUS, URPX, and CUPID projects; advances Power Grid Model to Early Adoption; and highlights a TenneT case study demonstrating a 10x performance improvement using PowSyBl. Recent releases across EVerest, OperatorFabric, FlexMeasures, and other projects underscore continued momentum across the LF Energy ecosystem.
The Grid Doesn’t Wait for a Requirements Document
Hugo Pfister, Manager Grid Security Applications, TenneT Netherlands TL;DR:TenneT shows that embedding software development directly within grid operations, rather than separating “business” and IT, enables faster iteration, better use of domain knowledge, and more effective tooling. Built on the open source PowSyBl framework, this model improves performance while leveraging shared infrastructure and community-driven development. The…
Grid Security at Scale: How TenneT Built a 10× Faster Analysis Platform on PowSyBl
Summary Signal: TenneT TSO B.V. achieved a 10× performance improvement in grid security analysis by building ReFlow, an orchestration platform powered by the LF Energy open source project PowSyBl. The solution reduced grid calculation times from minutes to seconds, deployed in five months, with no proprietary licensing required. Download the pdf → The challenge At…
PowSyBl Community Releases powsybl-dependencies 2026.0.0
The PowSyBl community has released powsybl-dependencies 2026.0.0, which concludes the last PowSyBl release train. PowSyBl is an open source library dedicated to electrical grid modeling and simulation. This release aligns versions across the PowSyBl ecosystem. Repository versions and links to specific release notes are provided in the table below. Repository Versions Repository Version powsybl-core 7.2.1…
Related Videos
Lightning Talk: Forecasted Congestion Management Using Plug and Play Model - Ankur Arohi
Open Source for Power Grids: The Business Model of a Service Provider - Nicolas Omont, Artelys
Continental-Wide Coordination of the Power Grid Powered by PowSyBl
Model Your Power Grid with PowSyBl - Anne Tilloy & Jon Harper







LFE Project PowSyBl: Grid Modeling at the Core of Europe’s Power Grid Planification... Nicolas Omont
September 22, 2025 7:41 am