LF Energy Summit Europe 2026

Several related power system planning model interoperability initiatives will share their latest progress, challenges, and real-world applications, including consideration of the differing needs of different end users. Panelists will discuss the potential to align efforts and the challenges and opportunities in delivering both a more effective and more streamlined future modeling experience for end users, from grid operators to energy ministries to civil society. Presenters will cover where models overlap, where models diverge, and what the realistic boundaries are for interoperability, and will invite participants to consider which standards will likely align and which will remain distinct, both in the electricity/TSO/DSO domain and in the sector coupling/multi-commodity domain. Session panelists and participants will discuss the anticipated ways that system planning modeling will change in the next decade and how to future-proof interoperability.

Participants may include: NLR (Sienna/GDM), Princeton (GenX), VTT/Nodal Tools (CESM), TU Berlin (PyPSA), OET, Encoord, TZ, RTE, AFRY, Recognis, EPRI, Imperial College (OSeMOSYS), ENTSO-E, SOPTIM (CGMES), Sylvan

Remedial Action Optimisation (RAO) is becoming a key operational capability to manage interconnected power systems across Europe. As requirements evolve and implementations mature, there is a growing need for coordination between stakeholders contributing to and relying on shared solutions.
This Birds of a Feather session is an open, collaborative forum around PowSyBl OpenRAO, bringing together developers such as Artelys, TSOs such as RTE, and RCCs such as Coreso to exchange on experiences, ongoing work, and upcoming priorities.
RTE and Artelys will present developments carried out on OpenRAO over the past year and those planned for the next (algorithmic improvements, countertrading within the optimisation core, …), with a focus on alignment with requirements from ongoing projects, notably SWE ROSC for Coreso. The session will also explore connections with related initiatives, including ToOP.
Rather than a one-way presentation, we will focus on interaction: participants will be invited to share plans, challenges, and expectations regarding OpenRAO. The objective is to foster convergence, encourage contributions, and strengthen a shared vision for OpenRAO within the LFE community.

Energy systems are undergoing rapid transformation as sector coupling intensifies and variable renewable generation grows, creating a pressing need for flexible and transparent modeling tools. While many open-source frameworks offer rich features, extending them with new mathematical models typically requires writing custom software, a barrier for many analysts.

We present GEMS (Generic Energy Systems Modelling Schema), a high-level modelling language designed to make multi-energy system adequacy and planning studies both more expressive and more accessible. GEMS brings model definitions out of the codebase and into simple YAML configuration files, where users describe variables, parameters, and constraints using natural mathematical expressions. These expressions are parsed into abstract syntax trees and automatically expanded into a complete optimization problem. This model-agnostic architecture enables rapid experimentation, lowers development and maintenance costs, and promotes true reusability: adding a new model requires no code, only data. The language is already supported in Antares Simulator and in the Python package GemsPy.

Operating highly loaded grids in real time requires combining powerful topology optimisation with efficient handling of “linear” remedial actions. ToOp, developed by 50Hertz, is a state-of-the-art optimiser for topological measures, going beyond the topology optimisation currently available in OpenRAO.

In TopRAO, we couple ToOp with the Powsybl-based OpenRAO toolbox: OpenRAO optimises linear remedial actions (PST, redispatching, counter-trading, HVDC), while ToOp focuses on topological measures. Together, they form a real-time-capable RAO engine for security analysis at TSO and inter-TSO level.

This demo walks through an end-to-end workflow: importing network data, running joint optimization of topology and linear actions, and analysing resulting constraints, actions and costs using open, transparent components.

Modern grid control systems require interoperable, scalable, and vendor-neutral data infrastructures. While CIM/CGMES has become the standard exchange format for power system models, many implementations still treat it primarily as a file format instead of a semantic data platform.

This session presents practical experiences from building modern utility control system components using RDF, SHACL, SPARQL, Apache Jena, and open-source tooling. We will show how semantic technologies can evolve from offline model exchange into high-performance, real-time knowledge graph infrastructures for power systems.

Topics include high-performance in-memory RDF graph processing, SHACL validation for operational grid models, lessons learned from Apache Jena internals, and the development of open-source tooling such as RDFArchitect and OpenCGMES.

The session shares real-world insights from developing software for transmission system operators and discusses how open semantic infrastructures can support interoperable and future-proof digital energy systems.

Open-source energy models are becoming increasingly important for transparent and reproducible energy planning. At the same time, many institutions still rely on proprietary software for day-to-day planning and decision-making. Closing this gap requires more than open code. Open-source tools also need the functionality, reliability, and long-term support expected by industry users.

This session presents the PyPSA-Taskforce, a joint initiative by Technische Universität Berlin, Università di Pisa, and Open Energy Transition to strengthen PyPSA as a professional open-source tool for energy system planning. The Taskforce focuses on improving areas of PyPSA that are still missing or not yet mature enough for wider industry adoption.

The project focuses on developing and integrating capabilities needed for real-world planning applications while maintaining the transparency and flexibility that make open-source tools valuable. At the same time, it aims to move beyond the limitations of proprietary software by building a tool that can evolve openly with the needs of the energy transition.

On 28 April 2025, continental Spain and Portugal experienced a total blackout, while the rest of the European grid was largely unaffected. This most severe European blackout in over 20 years is analysed using a time-domain model of the Iberian system derived from an anonymised network snapshot. In its final report on the incident, ENTSO-E’s Expert Panel identifies LF Energy’s Dynaωo, an open-source, industrial-grade suite of simulation tools, as the basis for its independent voltage stability study. Simulations closely reproduce recorded measurements and clarify the roles of cross-border exchanges, TSO-DSO interactions, distributed renewable energy sources and limited reactive power margins in the voltage rise that triggered the cascade. The study highlights the value of relying on an open-source industrial tool and shows how Dynaωo has evolved into a robust, high-performance solution. The presentation will detail the modelling and simulation approach, key challenges, and the main insights gained on the 28 April 2025 events, demonstrating how Dynaωo delivers the level of transparency, reproducibility and scientific rigour now expected for the analysis of major power system events.

DyCoV (Dynamic Compliance Verification) is an Open-Source tool built by RTE for bringing transparency to the process of verifying grid-code compliance of the dynamic behavior of new generation facilities. It contemplates both *electric performance* (i.e., "does the behavior pass the requirements?") and *generic model validation* (i.e., "does the model match the actual behavior?").

The tool builds upon Dynawo, RTE's Open-Source dynamic simulator, which in turn uses Open Modelica for its RMS models, including WECC and IEC generic models. This provides a fully transparent process for all stakeholders, thus avoiding the pitfalls of proprietary models and black-box tools. In addition, DyCoV removes the drudgery of measuring, comparing, and extracting all required KPIs from curves: rise/settling times, FRT responses, point-wise diffs, etc.

The tool is built with Python and structured as a series of independent tests, each producing its own report in PDF. The current tests correspond to RTE's connection grid code (DTR document), but DyCoV design uses templating (Jinja) and configuration files to make it easily adaptable to other grid codes, avoiding code changes as much as possible.

Modern AI for power flow and OPF is on the rise, but it will still require large amounts of trustworthy training data and strong conventional solvers for validation (“solver‑certified AI”). An important application are adjacent‑state studies needed for N‑1 screening and decision planning. This session argues that classic algorithms will not vanish, but must be redesigned for batch computation: solving many related grid states faster than repeated Newton-style runs. We reshape ideas from perturbation theory into a load-flow solver pattern that reuses structure across scenarios and maps well to parallelizable hardware. We introduce the key mathematics behind the approaches including the holomorphic embedding load flow method (HELM) and related methods. We then show how to turn them into an engineering workflow that can outperform repeated Newton-Raphson solves in high-throughput studies. We close with an open roadmap: an industrial‑grade implementation under development at 50Hertz/Elia Group and a clear invitation to collaborate on open interfaces, benchmarks, and integration with LF Energy tooling.

Power Grid Model is a high-performance, open-source calculation library built for advanced distribution system analysis.

This joint presentation by Alliander and SOPTIM tells a story of open source collaboration and innovation between a Grid Operator and Vendor within the LF Energy Power Grid Model (PGM) project.

Alliander—maintainer of the Power Grid Model project—and SOPTIM—a key contributor—have met each other at a LF Energy summit, which has led to a productive partnership, including shared development efforts, knowledge exchange, and the introduction of new features that enhance the capabilities of the model.

Overall, the presentation provides a tangible example of how open collaboration within LF Energy can drive innovation, strengthen ecosystems, and accelerate the development of open-source solutions for the energy sector, while also diving into the technical part of new features that support the various use cases at Alliander and SOPTIM.

Grid operations are becoming fundamentally more complex. The classical DC load-flow worked well in the past, but its simplifying assumptions are increasingly violated in modern grids with high renewables, reactive power flows, and tighter operational margins.

DC+ is a voltage-sensitive linearization of the AC load flow that retains voltage magnitude, angles, and reactive power while remaining orders of magnitude faster than full AC solvers.
Conceptually, it corresponds to a single Newton step around the AC base case, capturing the direction and severity of violations far more accurately than classical DC, while scaling to millions of N‑1 evaluations per second on GPUs.

DC+ enables a new class of scalable, open optimization workflows:
Potential use cases of DC+ are:
- Fast contingency screening and ranking?
- Topology optimization with voltage awareness?
- Security constrained voltage Optimization?