Trade-offs between sustainable development goals in systems of cities

TL;DR

This paper uses a stylised simulation model of urban systems to explore the inherent trade-offs between sustainable development goals, revealing multiple compromise regimes rather than a single optimal solution.

Contribution

It introduces a bi-objective optimization framework for urban systems, highlighting the diversity of sustainable development trade-offs in cities.

Findings

No single urban optimum exists for emissions and innovation.

Multiple regimes form as compromises between sustainability and innovation.

Urban systems exhibit diverse trade-off solutions rather than a unique optimum.

Abstract

Sustainable Development Goals are intrinsically competing, but their embedding into urban systems furthermore emphasises such compromises, due to spatial complexity, the non-optimal nature of such systems, and multi-objective aspects of their agents, among other reasons. We propose in this paper to use a stylised simulation model for systems of cities, focused on innovation diffusion and population dynamics, to show how trade-offs may operate at such a scale. We proceed in particular to a bi-objective optimisation of emissions and innovation utilities, and show that no single urban optimum exists, but a diversity of regimes forming a compromise between the two objectives.