Energy planning tools are crucial to Europe’s energy transition. They guide network development, market design, investment decisions and regulatory oversight. Most of the widely used tools today are proprietary and often supplied by vendors outside Europe. This creates strategic exposure. Prices can rise unexpectedly. Licences can change. Vendors can be acquired or pressured by their home jurisdictions. And sensitive data may fall outside European legal control. For a sector as fundamental as energy, this raises a simple question: who controls the digital infrastructure that underpins Europe’s planning capabilities? Open-source models offer a more secure, transparent and sovereign alternative.

Digital sovereignty

Digital sovereignty means having strategic control over the technologies, data and infrastructure that underpin Europe’s economy and public institutions. The World Economic Forum describes it as the ability to shape one’s own “digital destiny”. The European Commission’s Digital Commons EDIC and the Summit on European Digital Sovereignty reflect growing political recognition that critical digital systems must be governed on European terms. Organisations such as Germany’s Sovereign Tech Agency and the Linux Foundation are likewise strengthening Europe’s open-source foundations.

Recent incidents have shown why this matters. In 2024, the European Data Protection Supervisor ruled that the Commission’s use of Microsoft 365 violated institutional data-protection rules, forcing compliance changes and exposing the fragility of this dependence. Data protection authorities in several countries have banned Microsoft 365 in schools. Denmark has begun migrating government staff to LibreOffice to reduce reliance on foreign suppliers. The International Criminal Court has reportedly moved to open-source alternatives, ostensibly after complications linked to US sanctions. And a global outage triggered by a proprietary software update in 2024 disrupted flights, payments and public services across Europe. Together, these episodes underscore the need for digital tools that Europe can inspect, govern and secure on its own terms.

Why energy models are critical infrastructure

Energy system models guide decisions with multi-billion-euro implications. They shape grid expansion, determine flexibility needs, inform adequacy assessments and structure long-term investment. For decisions of such magnitude, blind trust in opaque proprietary models must give way to the evidence-based transparency enabled by open-source software.

The European Alliance for Industrial Data, Edge and Cloud stresses that sovereignty extends from data to the technologies and algorithms that process it. In energy planning, this is decisive. Europe cannot claim control over the energy transition while depending on external vendors for the digital systems that determine how that transition is designed. In contrast, open-source models meet the requirements of transparency, verifiability and local control. They can be operated, maintained and adapted within Europe, ensuring continuity even if commercial or geopolitical conditions change.

Open models as a strategic asset

Digital sovereignty in energy is not about withdrawing from global collaboration. It is about ensuring that the tools guiding Europe’s transition remain under European control. Open-source models provide full insight into modelling logic, long-term independence from vendor lock-in and the flexibility to adapt tools as technologies, market designs or policies evolve.

As digital infrastructure becomes a strategic asset in its own right, open and inspectable tools offer a far more resilient foundation than closed systems whose availability or functionality cannot be guaranteed.

Key advantages of open models

Open models bring many benefits for operators, regulators and policymakers. Three stand out in the context of digital sovereignty:

- Collaboration: Coordinated planning depends on transparent and interoperable tools. Recent analyses show that better-aligned European grid planning could save more than 500 billion euros by 2050. Open-source models enable scrutiny of assumptions, reproducible methodologies and seamless data exchange across borders, creating a shared analytical foundation for TSOs, DSOs, regulators, academia and industry.

- Security: Open code can be audited by internal teams or by the wider ecosystem, reducing the risk of hidden vulnerabilities. The infrastructure that powers the internet and most cloud services already relies on open foundations for this reason. Energy models are no exception: transparency enables institutions to verify how data is handled and processed while maintaining secure environments for confidential datasets.

- Cost resilience: Open-source licenses eliminate recurring software fees and reduce exposure to vendor lock-in, price increases or licence changes. Support and training can be obtained from a competitive market of providers rather than a single vendor, giving organisations long-term control over both technical and financial aspects of essential planning tools. Students and employees can self-learn using open source models for free.

Across Europe, open-source energy models are already in use. NGOs employ them for a range of use cases, from assessing the future of Ukraine’s energy system, to employing open APIs and energy modeling tools for policy electricity reviews. ACER uses open methodologies for flexibility needs assessments. System operators increasingly rely on mature frameworks such as PyPSA and PowSyBl. These tools are peer-reviewed, widely deployed and supported by active communities in academia and industry.

Their advantages extend beyond transparency. Open models can integrate with emerging European data spaces, adapt quickly to new policy questions and support secure combinations of open data and confidential operational datasets. They facilitate interoperability across borders, which is essential for planning in Europe’s highly interconnected system.

Europe does not need to wait. High-quality open-source models already exist. Integrating them into upcoming planning cycles is one of the most practical steps organisations can take to strengthen digital sovereignty and ensure long-term control over critical infrastructure.