At LF Energy Summit Europe 2026, Nathalie Lemaître of RTE and Sébastien Scarmure of Elia Group made the case for deeper collaboration among European transmission system operators as software becomes more central to grid operations.
In “Pooling Code, Keeping Control,” Lemaître described open source as part of the operating fabric of critical infrastructure, while Scarmure argued that digitalization is now at the core of the TSO business. Lemaître connected collaboration with preserving technological choice and avoiding dependency or fragmentation, while Scarmure emphasized reducing duplication, accelerating innovation, and improving interoperability.
Open source has crossed a threshold
Lemaître opened with the April 28, 2025 blackout on the Iberian Peninsula. The European expert panel investigating the event selected Dynawo, an open source dynamic simulation platform developed at RTE and hosted by LF Energy, for analysis of the grid event.
For Lemaître, that choice showed how far open source has moved in the sector.
“It’s no longer an experiment. It has become part of the operating fabric of critical infrastructure.”
Lemaître said RTE began this journey in 2018 as a founding member of LF Energy because some challenges were too large to solve alone.
Eight years later, Lemaître described LF Energy as an industrial collaboration platform delivering operational value, with projects being used in mission-critical environments and developed collectively by system operators, technology providers, and software companies.
Collaboration can reduce duplication and accelerate innovation
Lemaître argued that collaboration is not simply about reducing costs. It can also accelerate innovation.
One example came from TenneT Netherlands, which put ReFlow into production in April. Lemaître said the platform delivered a 10-fold performance improvement for security analysis calculations, reducing processing times from minutes to seconds, with five months from project launch to the first production deployment.
Lemaître used the example to show how shared development can compound. RTE invested, TenneT benefited from and improved the platform, and those improvements can then benefit the wider community, including RTE.
That model matters because European system operators are facing different versions of many of the same challenges, including decentralized renewable generation, electrification, battery storage, increasingly complex markets, data center growth, and artificial intelligence.
Rather than solving similar software problems repeatedly through separate procurement and development efforts, Lemaître argued that TSOs can solve more of them together.
Sovereignty means preserving choice
Lemaître connected collaboration directly to technological sovereignty.
“Sovereignty does not mean isolation. It means preserving choice.”
That includes avoiding dependency on a single vendor, but Lemaître also warned against fragmentation.
With organizations and budgets already stretched, endless duplication of effort creates another form of weakness. Lemaître argued that international collaboration should therefore be treated as a strength rather than a vulnerability.
LF Energy, Lemaître said, provides trust, governance, a neutral environment for collaboration, and an ecosystem of operators, vendors, integrators, and developers.
Open source still requires investment, governance, and trust
Lemaître was also explicit that open source does not remove the work required to sustain collaboration.
Successful cooperation requires investment, governance, and trust. At RTE, that meant empowering developers to contribute to a broader ecosystem and accepting that some decisions would become collective.
Lemaître also said community investment can create more value than local optimization.
After eight years of experience, Lemaître said the benefits had far exceeded the effort.
Digitalization is becoming core to the TSO business
Scarmure followed with Elia Group’s perspective on digitalization, cooperation, and open source.
“Digitalization is in fact the business of the TSO.”
Scarmure described practical questions around infrastructure, application development, governance, and where open source technology fits as Elia Group manages both physical and digital infrastructure.
Scarmure also described work on a shared digital environment intended to improve grid coordination and information exchange. The central point was that such an environment cannot be built by one organization alone.
Elia Group wants to collaborate more
Scarmure said working in standalone mode creates duplication and slows innovation. Greater cooperation can reduce costs, improve efficiency, support further innovation, and strengthen interoperability.
That also means agreeing on more of the underlying technology. Scarmure called for greater alignment on technology stacks, integration, and shared services so organizations can work together more effectively.
Scarmure said collaboration should not stop at Elia Group’s organizational boundaries and called for deeper partnership with other organizations.
Open source is central to that approach. Scarmure described open source as a normal way to collaborate and said Elia Group needs to accelerate its participation.
“Open source, it’s at the top of our agenda. Partnership too.”
Pooling code while keeping control
Across both parts of the keynote, Lemaître and Scarmure argued that European TSOs do not need to build every foundational software capability independently.
Taken together, the two perspectives point toward deeper collaboration on software foundations that TSOs increasingly share. Lemaître emphasized preserving choice through governance and avoiding dependency or fragmentation, while Scarmure emphasized working together to reduce duplication, move faster, and improve interoperability.
Watch the keynote
Watch the full keynote, “Pooling Code, Keeping Control.”
Frequently asked questions
Why did Nathalie Lemaître argue for more collaboration among European TSOs?
Lemaître said European system operators face different versions of many of the same software challenges on similar timelines and with similar resource constraints. Collaboration can reduce duplicated work and accelerate innovation.
How did Lemaître define technological sovereignty?
Lemaître said sovereignty does not mean isolation but preserving choice, including avoiding dependency on a single vendor while also avoiding fragmentation.
What was Sébastien Scarmure’s message about open source?
Scarmure said digitalization is increasingly core to the TSO business and argued for deeper cooperation on interoperability, technology stacks, integration, and open source collaboration.
About LF Energy
LF Energy is the Linux Foundation’s neutral home to build the digital foundation for energy together. We host more than three dozen open source projects used to plan, operate, and modernize energy systems. The portfolio spans from transmission system modeling to substation virtualization, smart meter integration to EV charging. We provide the trust layer: neutral governance, legal frameworks, security practices, and community of practitioners that turn open source software, standards, and data into infrastructure the industry can depend on for decades. Members include utilities, energy companies, vendors, researchers, and technology providers, aligned to deliver affordable, reliable, safe, and clean energy. For more information, please visit lfenergy.org.
About The Linux Foundation
The Linux Foundation is the world’s leading home for collaboration on open source software, hardware, standards, and data. Linux Foundation projects are critical to the world’s infrastructure including Linux, Kubernetes, Node.js, ONAP, PyTorch, RISC-V, SPDX, OpenChain, and more. The Linux Foundation focuses on leveraging best practices and addressing the needs of contributors, users, and solution providers to create sustainable models for open collaboration. For more information, please visit linuxfoundation.org.
AI Disclosure
This post used artificial intelligence tools for research, structural assistance, or grammatical refinement. The final content was reviewed, edited, and validated by human contributors to LF Energy to ensure accuracy and alignment with our community standards. We remain committed to transparency in the use of generative technologies within the open source ecosystem.
Last updated: October 27, 2026