Urban Autophagy

Drawing from cellular biology, Hannibal Newsom introduces the concept of Urban Autophagy—a speculative yet actionable paradigm that reimagines sustainable urbanism through the metaphor of biological autophagy, the regenerative process by which organisms self-consume dead or damaged components to promote health and longevity; applying this model to urban environments, the essay frames cities not as extractive entities dependent on external inputs but as metabolic systems capable of cannibalising their own spatial, material and infrastructural excesses for renewal and resilience, challenging the linear resource flows and globalised supply chains that currently dominate urban growth; Newsom outlines existing urban mining, adaptive reuse, and infrastructural retrofitting as nascent practices that already echo this principle, but argues for a systematic, policy-driven adoption of autophagic logics that foreground decay, obsolescence and embedded value not as failures but as latent resources; the essay proposes a methodological triad: identification of endogenous resource nodes (e.g. abandoned buildings, underused streetscapes), strategic deconstruction for material and spatial reintegration, and public imaginaries that reframe decay as opportunity—thus transforming waste into agency; examples include cities reconfiguring vacant lots into urban agriculture loops, converting former industrial districts into carbon sinks or creating closed-loop housing economies using materials sourced from demolition within a city’s own perimeter; fundamentally, Urban Autophagy offers an ontological inversion of growth, prioritising immanent transformation over expansion, and requiring a new aesthetics, ethics and epistemology of urban stewardship aligned with planetary boundaries; in doing so, it envisions not merely greener cities but self-aware urban metabolisms capable of sustaining themselves within the limits of environmental and geopolitical turbulence. Newsom, H. (2022) Urban Autophagy: A New Imaginary for Twenty-First Century Urban Growth. The Plan Journal, 7(1). https://doi.org/10.15274/tpj.2022.07.01.5

Digital Twins as Catalysts for Urban Sustainability

The Barcelona Circular City model, presented by vCity and documented in recent simulations and reports, exemplifies how Digital Twins function as vital instruments for designing and monitoring urban transitions toward sustainability; by virtually replicating city systems in real time, these models enable urban planners to simulate, evaluate and optimise infrastructure, transport, energy and waste management under a holistic lens, integrating social, economic and ecological indicators into a single decision-making environment, especially when guided by frameworks like the Circular City Index, an open-data tool that benchmarks municipal progress across Spain, fostering comparability, policy learning and accountability through a reproducible methodology anchored in transparency and inclusivity, as demonstrated in applications ranging from mobility flows in Viladecans to charging station coverage in Barcelona, where complex spatial datasets are transformed into actionable insights; for instance, in the case of the 15-minute city simulation for Barcelona, the model exposed areas of uneven accessibility to basic services, prompting tailored interventions such as redistributed libraries and expanded metro access, thus evidencing how the digital twin does not merely reflect urban reality but proposes corrections to its inertia, which is further illustrated in the comprehensive report “Circular Barcelona: A New Urban Model” (October 2025), where digital infrastructure and circular economy converge in a civic-technological alliance for resilient futures, co-funded by European recovery programmes and hosted at the Barcelona Supercomputing Center, this initiative operates at the crossroads of research, policy and digital transformation, empowering local governments to shift from reactive to anticipatory planning while anchoring decisions in measurable sustainability metrics. vCity (2025) Report. Circular Barcelona: A New Urban Model. Barcelona Supercomputing Center, https://vcity.tech