Social Digital Twins and the City: A catalyst for the creation of Net Positive Cities

Fujitsu / December 5, 2025

Trusted Society Digital Shifts AI Data and Security Public Sector

Cities have always been engines of human progress. They concentrate talent, creativity, and opportunity but also magnify challenges. As urban populations are projected to approach 70 percent of the global total by 2050, cities will face escalating pressures on housing, mobility, health, and sustainability. Infrastructure designed for earlier centuries is straining under the demands of an interconnected and unpredictable world.

For years, the prevailing model of “smart cities” has focused on optimization—using technology to increase efficiency and reduce waste. Yet efficiency alone no longer suffices. Cities must evolve from minimizing harm to generating net positive outcomes: regenerating ecosystems, promoting social equity, and improving human wellbeing.

This shift requires a new kind of intelligence one that understands and anticipates the dynamic interplay between people, infrastructure, and the environment. Fujitsu’s Social Digital Twin (SDT) offers precisely that capability: a platform for creating adaptive, data-driven urban systems that enable cities not merely to sustain, but to renew themselves.

From Smart to Net Positive Cities: The Rise of the Social Digital Twin
Understanding Social Digital Twins
Turning Data into Collaborative Insight
Real-World Impact: Social Wellbeing in Japan
The Net Positive Framework in Practice
Reimagining Value Creation
Creating a New Urban Operating System
Fujitsu’s Broader Vision: The Trusted Society
The Path to Net Positive
Conclusion

From Smart to Net Positive Cities: The Rise of the Social Digital Twin

For over a decade, the dominant narrative in urban innovation has centered on “smart cities,” where sensors, data, and algorithms drive operational efficiency. While such advances have improved service delivery, they have not necessarily improved lives. A city can optimize traffic or reduce emissions while still deepening social fragmentation or eroding natural capital.

Fujitsu and The Economist Impact articulate a more ambitious vision through the concept of Net Positive. A Net Positive city or organization “puts back more into society, the environment, and the global economy than it takes out.” It is regenerative by design enhancing biodiversity, inclusion, and wellbeing while strengthening economic resilience. Advancing Net Positive | Fujitsu Global

In this paradigm, technology becomes a means to a broader end. Data is used not just to perform better, but to restore, rebalance, and reimagine the urban ecosystem. Achieving this transformation requires deep insight into how human behavior, policy, and infrastructure interact a challenge that Social Digital Twin^TM are uniquely positioned to address.

Understanding Social Digital Twins

Conventional digital twins replicate physical assets such as buildings, transport systems, or energy grids to model performance or predict maintenance needs. Fujitsu’s Social Digital Twins extend this concept by integrating real-world data about people, organizations, and communities into virtual ecosystems. https://keytechshowcase.com/category/social-digital-twin/

By combining behavioral, environmental, and economic data, SDTs enable cities to simulate how policies or projects might play out before implementation. For example, rather than modeling traffic patterns in isolation, an SDT can analyze how changing transport pricing affects commuting behavior, carbon emissions, and local economies simultaneously. Similarly, it can test how investments in green spaces might improve mental health, stimulate small business growth, and lower healthcare costs.

Infographic on Digital Rehearsal Technology, featuring a layered digital city interacting with the real world, and a multi-aspect simulator diagramming CO2 emission, availability, convenience, behavior selection models, loss, opportunity, profit, and consensus-building among citizens, enterprises, and administrators.

See: "Social Digital Twin" Technology

In doing so, the Social Digital Twin^TM reveals the social systems behind physical systems how choices ripple through communities, economies, and environments. It aligns closely with Fujitsu’s Trusted Society vision, where digital innovation enhances wellbeing, inclusivity, and planetary health. These digital environments become the basis for models that are fusing data from IoT sensors, government records, and ecosystem interactions into a coherent platform for evidence-based collaboration.

Turning Data into Collaborative Insight

Creating a Net Positive city requires collaboration on an unprecedented scale. Governments, businesses, universities, and citizens each hold pieces of the urban puzzle, yet their efforts are too often fragmented. Data remains locked in silos, policies are developed in isolation, and unintended consequences proliferate.

Fujitsu’s Social Digital Twin^TM offers a shared platform where diverse stakeholders can see the same evidence, test assumptions, and coordinate action. By integrating data from transportation, healthcare, energy, environmental, and social systems, the SDT provides a comprehensive view of urban dynamics.

This shared model transforms debate into informed dialogue. City authorities can evaluate how electrifying a bus fleet affects noise, air quality, and community health. Housing agencies can assess how zoning reforms influence mobility, energy use, and equity. The SDT allows decision-makers to visualize interconnected consequences turning uncertainty into clarity and competition into cooperation.

Real-World Impact: Social Wellbeing in Japan

Fujitsu’s Social Digital Twin^TM is already demonstrating tangible results in Japan. In one city, planners used an SDT to explore the relationships among mobility, health, and lifestyle. By merging anonymized transport data, public health records, and demographic insights, the analysis revealed that improving walkability around key transport hubs not only reduced emissions but also boosted physical activity and lowered long-term healthcare costs.

This example illustrates a fundamental insight: modest changes, when viewed through a systems lens, can yield disproportionate benefits. By understanding such interconnections before acting, city leaders can prioritize interventions that generate the highest combined value for people and the planet.

Fujitsu is expanding this work into disaster resilience, using SDTs to simulate emergency responses and optimize resource deployment under varying scenarios. Across applications, the goal remains consistent to build self-learning systems that enhance society’s ability to anticipate, adapt, and thrive.

The Net Positive Framework in Practice

Both Fujitsu and The Economist Impact emphasize that achieving Net Positive outcomes demands an ecosystem mindset. No city becomes regenerative through technology alone; it requires alignment across sectors and shared commitment to public value. Our whitepaper on Net Positive Cities further develops this concept. From Smart Cities to Net Positive Results | Fujitsu Global

Social Digital Twins make this possible by creating a neutral data commons, a transparent and trusted space for cross-sector collaboration. For example, during urban heatwaves, energy utilities, health services, and local communities can use an SDT to identify vulnerable areas, coordinate responses, and monitor effectiveness in real time. This strengthens resilience while ensuring that the most affected populations receive attention first.

In this sense, SDTs embody what The Economist Impact calls “inclusive innovation” solutions that extend the benefits of technology to all citizens, not only those at the center of power. Fujitsu’s approach places ethical, participatory, and transparent decision-making at the heart of digital transformation, ensuring that progress is measured not only by efficiency but by empathy.

Reimagining Value Creation

At the core of the Net Positive philosophy lies a redefinition of value itself. Traditional metrics such as GDP or cost reduction overlook critical dimensions of urban health social capital, ecological regeneration, and resilience. Social Digital Twins help make these intangible factors visible and measurable.

By quantifying the co-benefits of policy choices from cleaner air, improved mental health, and enhanced biodiversity, cities can reframe investment and performance around holistic prosperity. This evidence base can attract new funding models, from green bonds to impact finance, aligning economic incentives with social and environmental outcomes.

Furthermore, cities equipped with SDTs move from reactive to proactive governance. Instead of responding to crises such as congestion, flooding, or energy shortages, they can model, anticipate, and prevent them. Predictive intelligence enables limited resources to be deployed strategically, maximizing collective gain and resilience.

Creating a New Urban Operating System

The Social Digital Twin provides the operational intelligence required to manage cities as adaptive, learning systems. By continuously integrating new data and simulating alternative futures, it allows leaders to adjust and refine strategies dynamically. Policies can be tested virtually, monitored in real time, and optimized as conditions evolve.

This represents a profound shift in governance that reacts to events to designing for resilience and regeneration. Cities become self-improving entities capable of evolving alongside environmental pressures, economic shifts, and demographic change.

Fujitsu’s Broader Vision: The Trusted Society

At its heart, the Social Digital Twin is a key component of Fujitsu’s broader vision for a Trusted Society, a world where technology helps to enhance human insight, fairness, and collective wellbeing.

By integrating AI, analytics, and cloud infrastructure with a clear social purpose, Fujitsu helps governments and organizations align digital transformation with the public good. The Social Digital Twin serves as a bridge between data and empathy, turning predictive capability into purposeful action.

Through this lens, cities can evolve from being merely “smart” efficient but impersonal to becoming “wise”: capable of learning, caring, and contributing more to society and the planet than they consume.

The Path to Net Positive

Realizing the full potential of Social Digital Twins requires leadership commitment and multi-sector collaboration. Governments must design governance models that protect individual rights while enabling open data exchange. Businesses must treat participation in data ecosystems as an investment in long-term resilience. Citizens, meanwhile, must be engaged as active partners in shaping the digital commons.

The most forward-looking cities will base their Social Digital Twin on net positive ecosystems, by developing shared platforms for experimentation, learning, and co-creation. In these environments, the boundaries between government, enterprise, and community blur, and shared intelligence drives shared progress.

Conclusion

The next generation of urban innovation will be measured not only by efficient operations, but also by how effectively it helps regenerate environments and contributes to social value. The same is true for their use of AI. Rather than measuring intelligence based on the number of sensors, processes, and agents, we must measure it based on the degree to which insights enhance human and ecological well-being.

Fujitsu’s Social Digital Twin offers a powerful pathway toward this transformation. By integrating behavioral, environmental, and economic data into adaptive models, it enables leaders to design policies that are not just sustainable but restorative.

The Net Positive city is no longer an abstract vision; it is an emerging reality. Through the power of Social Digital Twins, we can create cities that learn, adapt, and give back more than they take.

To explore how Fujitsu can help your organization or municipality harness Social Digital Twins to shape Net Positive cities and communities, visit: https://keytechshowcase.com/category/social-digital-twin/

Nick Cowell

Nick is a technologist and futurist with extensive experience in hardware, software, and service development, having previously worked for leading technology providers across the USA, Europe, and Oceania. Nick was a Principal Consultant & Fujitsu Distinguished Engineer within the Fujitsu Global Technology Strategy Unit.

Dr. Martin Schulz

Martin’s work focuses on the impact of digitalization, government policies and corporate strategies. Today, he is Fujitsu’s Chief Economist, advises governments and teaches at the Mercator School of Management. His analyses are widely quoted in international media - with regular interviews at CNBC, NHK World etc. schulz@fujitsu.com