In the heart of Luxembourg, the city of Differdange is setting a powerful example for urban innovation and sustainability. As part of the EU’s "100 Climate-Neutral and Smart Cities by 2030" mission, Differdange is leveraging cutting-edge technologies—like Local Digital Twins—and collaborative governance to fast-track its path to climate neutrality. Partnering with the Luxembourg Institute of Science and Technology through the CitCom.ai project, the city is transforming data into action, proving that smart, sustainable solutions can be both practical and people-focused.
The solution
Differdange has started the road towards breaking down silos, changing its culture, and embracing a transformative governance model—both internally and in collaboration with its citizens. By promoting collective intelligence, the city is unlocking new avenues for innovation and creativity. In parallel, it is actively involved in numerous inter-communal and European projects, reinforcing its commitment to sustainable urban development.
Luxembourg Institute of Science and Technology is supporting Differdange in this ambitious journey, through the CitCom.ai project. Together, we have co-designed an experimentation roadmap towards adopting Local Digital Twins, developing a proof-of-concept tailored to the city's needs and enabling concrete and incremental use-cases that rely on real city data and challenges.
By accessing the Local Digital Twin via a web interface, city agents are now able to:
- Assess potential energy consumption of existing and simulated charging stations, and compensation using solar generation.
- Monitor energy consumption in public buildings to provide insights in detecting anomalies, optimizing energy use, and improving procurement strategies.
- Understand the efficacy of solar panel subsidisation to private citizens.
How we did it
Differdange is engaged in a strong and sustainable partnership with LIST, the operator of the CitCom.ai Testing and experimentation Facility - named Smart City Hub-, enabling to scope the best suited AI solution to the city missions, challenges and to its level of maturity in the different competence areas.
Well-defined experimentation plans, regular meetings and ideation workshops have enabled the co-design of the technological solution, with a strong focus on interoperability and open components, in order to match the city’s needs and to incrementally improve it with new features and developments. Regular and well-defined releases ensure that the Local Digital Twin remains the underlying purpose-fit asset and continuously adapts to the city’s needs.
Why join in an experiment with Luxembourg Smart City Hub
The Smart City Hub in Luxembourg is deeply engaged in the European Local Digital Twin Toolbox and the OASC working groups on Minimum Interoperability Mechanisms. By working with the Smart City Hub in Luxembourg, acting as an independent organization, cities benefit from:
- Access to validated AI solutions from the market that comply with the AI Act and other European regulations.
- Open-source solutions that prevent vendor lock-in, ensuring flexibility and scalability.
- Guided testing and experimentation, connecting cities with leading solution providers or integrating their existing technology partners.
- Resource efficiency by validating concepts before full-scale implementation.
Cities that engage with the TEF Site Luxembourg follow a structured, phased approach, moving from testing to validation based on their maturity level. The process begins with an initial scoping meeting to define specific needs and objectives, followed by a clear framework with milestone-driven experiments.
Why it’s reliable
At the TEF Site Luxembourg, cities don't just test technology—they build trust. Every experiment is grounded in transparency, security, and compliance, ensuring cities can confidently innovate while maintaining complete control. Here’s why:
- Data ownership: Partner cities retain full ownership of their data and solutions.
- Regulatory compliance: As a TEF, we ensure adherence to national and EU data and AI regulations.
- Transparency: A structured evaluation process with full documentation at every stage of the experiment.
Differdange is leading the way toward a smarter, greener future. By making the most of AI-driven solutions and collaborative governance, cities can turn ambitious climate goals into tangible results.
Explore how the TEF Site Luxembourg can support your city’s journey! Contact us at smartcityhub@list.lu to start your own experimentation and innovation process.
This article is authored by Laurence Johannsen, Andres Meléndez Imaz and Noé Marius.