Megaprojects as regime transformers: Analyzing the role of Norway's carbon capture and storage megaproject on port transition to energy hubs

Positioned at multisystem interfaces enables ports to diversify their services while facilitate decarbonization across maritime and nearby industries by embracing the role of low-carbon energy hubs, and small- and medium-sized ports (SMPs) are no exception to this trend. But empirical studies tend to privilege major ports or compare ports without adequately accounting for inherent differences in type and size. Given their limited yet agile capacity to respond to societal change, I focus on SMPs to explore how their transition unfolds in transformational contexts specifically influenced by low-carbon megaproject development. Megaprojects are large-scale, politicized, regulated initiatives that are conceptualized here as mission-oriented development programs comprising interrelated, coordinated initiatives governed by mission-oriented policies. Empirically, the study examines how Norway's carbon capture and storage (CCS) megaproject shapes SMPs' transition to energy hubs through qualitative data from semi-structured interviews and document review. Findings show that megaprojects entangle multiple systems and build multisystem interfaces across levels, catalyzing interrelated transitions through material, agentic, and institutional interactions. By creating protective spaces for specific technologies, megaprojects shape transition pathways at interfaces, gradually aligned them with regime-level transformation while increasing the risk of path-dependency given megaproject's strong regime interlinkages. This is particularly consequential for SMPs. Despite their limited capacity, strong alignment with megaproject can enable transition despite limited capacities while weak alignment risks stalling it. Yet SMP transitions remain nuanced, shaped by place-specific characteristics and local interlinkages. For policymakers, this highlights a critical tension: while megaprojects accelerate transition, they also heighten lock-in risks, necessitating long-term commitment to diversification and coordinated regulatory and incentive adjustments across interlinked low-carbon technologies. • Theoretical Innovation: Megaprojects reconceptualized as mission-oriented development programs that entangle multiple systems through technological, agentic, and institutional interlinkages, catalyzing interrelated transitions. • Empirical Method: Comparative analysis of Norwegian small- and medium-sized ports (SMPs) transitioning to energy hubs in a transforming regime driven by CCS megaproject development. • Paradoxical Impact: Low-carbon megaprojects drive niche development by shaping technological selection environments and invoking collective agency, driving niche at multisystem interfaces. Yet they might risk technological lock-in that prolongs incumbent regime dominance. • Place-Based Multisystem Dynamics: Despite their limited capacity, SMPs can leverage material, agentic, and institutional multisystem interlinkages with interconnected systems to demonstrate nuanced place-specific niches and diversify their service.