Article by Begoña G. Otero and Stefaan G. Verhulst: “The concept of digital twins has quickly become the new darling of the smart city world. By 2030, more than 500 cities plan to launch some kind of digital twin platform, often wrapped in dazzling promises: immersive 3D models of entire neighborhoods, holographic maps of traffic flows, real-time dashboards of carbon emissions. These visuals capture headlines and the political imagination. But beneath the glossy graphics lies a harder question: what actually makes a digital twin useful, trustworthy, and sustainable?
Having recently worked directly on a U.S. metropolitan digital twin pilot, we know the answer is not just shiny and sophisticated imagery. A genuine twin is a living ecosystem of different stakeholders and diverse datasets — integrating maps, open government data, IoT sensors, predictive AI models, synthetic data, and mobility data into a single responsive platform. Done right, a digital twin becomes a decision-making sandbox: where planners can simulate how pedestrianizing a street shifts congestion, for example, or how a Category 3 hurricane might inundate vulnerable neighborhoods.
If the initial rush of digital twin projects has taught anything, it’s that technology alone is not enough. Building a functional digital twin is as much an institutional and governance challenge as a technical one. The platform must integrate data from multiple sources, including government departments, private firms, utilities, researchers, and other relevant entities. Global leaders in the field, from Singapore’s Virtual Singapore to Orlando’s much-publicized holographic twin, have all discovered the same truth: the long-term value of a twin depends not on its graphics but on its data governance. Singapore’s twin works because its government mandated cross-agency data sharing. Orlando’s flashy prototype only turned serious when planners acknowledged that its future hinges on becoming an open ecosystem where utilities, agencies, and even residents can contribute data.
In practice, however, the necessary data is often scattered and siloed. European pilots have shown this clearly: the obstacle was not imagining use cases but finding and accessing the data to make them possible. In the OASC pilot regions, such as Athens and Pilsen, project teams reported that the biggest hurdle was that much of the relevant data sat in silos — owned by private firms, higher levels of government, or agencies unused to thinking of themselves as data stewards. Even when data existed, municipalities often lacked clear mandates, agreements, or technical workflows to integrate it responsibly.
The same applied in Helsinki, which today runs one of the most advanced city twins in Europe. Before reaching that point, the city had to spend years building a reliable data repository, common standards, and trust agreements with residents to ensure equitable use of information. Similarly, in the UK, the Gemini Principles and the subsequent National Digital Twin programme were born out of recognition that without shared governance, data would remain fragmented across sectors such as energy, transport, and the environment. Both cases show that even resource-rich contexts face governance hurdles first; technology comes later.
The lesson is clear: digital twins will only move beyond hype if we treat them as governance infrastructures, not visual spectacles. That means aligning the concept with frameworks of data governance, collaboration, and digital self-determination — in the process, ensuring that digital twins serve public purposes, respect local contexts, and empower communities to shape how their data is used…(More)”
