Humanity has spent a long-time shaping today’s living environment. Many cities have experienced development, and within these urban spaces, a wide range of services necessary for human activity are provided. These include housing and building structures that offer shelter functions; transportation systems enabling mobility; energy supply systems that drive urban operations; production systems that extract resources from nature and convert them into useful forms; and waste treatment and resource circulation systems that manage waste and recycle materials. Through these various systems that support urban life, mechanisms have evolved to autonomously enhance functionality, convenience, comfort, efficiency, safety, stability, cost-effectiveness, and environmental sustainability.

At the same time, it is now clear that, as seen in the tangible impact of climate change due to greenhouse gas emissions, our environmental burden is increasing beyond the limits of Earth’s ability to maintain stability-known as “Planetary Boundaries”*1. In response to this reality, requirements for achieving a sustainable society have been articulated-such as “carbon neutrality” in climate change mitigation and nature positive in ecosystem conservation. These developments call for the formulation of concrete strategies and their social implementation. However, the changes required are vast and urgent: for instance, to achieve the 1.5°C global warming target, carbon neutrality by 2050 demands an annual reduction rate of 4%. Therefore, mere improvements based on existing system structures are no longer sufficient. What is needed is structural change across systems and integration between them.

The Urban Energy Systems Lab of the Graduate School of Engineering, (The University of Osaka) has particularly focused on modeling energy demand within the housing and building stock and conducting scenario analysis toward decarbonization. Within this field, conventional measures have included introducing various energy-saving technologies, shifting energy sources in thermal applications like air conditioning and water heating, and promoting the use of renewable energy, primarily solar power. However, the IPCC’s Sixth Assessment Report*2 highlights the need to go beyond existing measures by adopting digital solutions, encouraging behavioral and lifestyle changes among residents and users, and promoting integrated operation between demand and supply sides of services. These broad perspectives are necessary to envision system change and advance integration across systems and sectors. Likewise, such extensive and rapid transformations are also required in related domains.

Urban Digital Twin Platform

Furthermore, Osaka Prefecture and City have been selected alongside Tsukuba City for the Japanese Cabinet Office’s Super City initiative. The Osaka Super City Project is involved in constructing the Osaka Regional Data Exchange Network (ORDEN), which is expected to evolve into a digital twin of the city. At The University of Osaka’s D3 Center, joint research on digital twins for smart cities and smart buildings is being conducted in collaboration with Daikin Industries through the D-child initiative. In addition, the center is researching evacuation simulations using digital twins, contributing to resilient urban development.

Given this background, the DX Society Research Division, the Institute for Open and Transdisciplinary Research Initiative, The University of Osaka and the Urban Energy Systems Lab are envisioning an action plan toward 2050 that includes building a Digital Twin*3 Platform for system integration. This platform will convert and visualize data related to housing, urban structures, and infrastructure into a 3D urban model. It will comprehensively incorporate operational and management data from various systems, enabling real-time understanding of current conditions and future projections within cities, while also supporting analyses based on transformation scenarios.

The platform will allow policymakers, planners, managers, and urban residents to intuitively understand and communicate with each other, facilitating policy decisions and municipal planning. Moreover, by integrating synthetic models simulating people’s locations, daily behaviors, mobility, and corresponding service demands, the platform will reconstruct inter-system relationships with high spatiotemporal resolution and enable real-time responsiveness, which will be useful for disaster response. Designed for scalability beyond Japan, the platform will be adaptable to rapidly developing cities across Asia and contribute to solving urban challenges around the world.

In collaboration with the DX Social Research Division, the D3 Center, the Urban Energy Systems Lab, the Smart City Strategy Department of Osaka Prefecture, and the Social Solution Initiative (SSI), the Inochi Forum will continue its efforts to build a shared urban data platform (Digital Twin Platform). Through this, it seeks to realize decarbonization, zero waste, and disaster resilience, thereby transforming cities into safe and sustainable environments where every Inochi unleashes its radiant light.

[Notes]

*1 The 2023 update to the Planetary boundaries. Azote for Stockholm Resilience Centre, based on analysis in Richardson et al 2023
https://www.stockholmresilience.org/research/planetary-boundaries.html

*2 IPCC, 2023: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, 184 pp., doi: 10.59327/IPCC/AR69789291691647.

*3 Alvi, M., Dutta, H., Minerva, R., Crespi, N., Raza, S. M., & Herath, M. (2025). Global perspectives on digital twin smart cities: Innovations, challenges, and pathways to a sustainable urban future. Sustainable Cities and Society, 126, 106356.
https://doi.org/10.1016/j.scs.2025.106356

[References]

・ORDEN
https://www.pref.osaka.lg.jp/o060020/tokku_suishin2/orden/index.html

・D-child
https://otri.osaka-u.ac.jp/dichild

・Architectural Morphology Cyber Community
http://www.comy.cmc.osaka-u.ac.jp/

・Urban Energy System Lab, The University of Osaka: Publications
https://see.eng.osaka-u.ac.jp/seeue/seeue/paper

・Cross-ministerial Strategic Innovation Promotion Program: Building a smart energy management system
https://www.jst.go.jp/sip/sems

[Action Platform]

Energy and Climate Change / Resource Recycling

[SDGs]