Understanding how multiple socio-technical systems transform in tandem has become an important frontier in sustainability transitions research. While the multi-level perspective has evolved into the multi-system perspective to conceptualise cross-system co-evolution, current studies largely overlook the relational micro-dynamics through which coordination and learning are enacted. To address this gap, this paper integrates experimental governance with the multi-system perspective to investigate how local experimentation can drive both single-system transitions and multi-system alignment. Drawing on policy analysis and 22 semi-structured interviews, we examine the Zhangjiakou wind-to-heat pilot in northern China, where wind power, district heating, electricity trading and emerging digital sectors became increasingly interconnected. Our analysis identifies a five-phase transition trajectory: dual-system coupling, incumbent system transition, emerging system reform, multi-system interaction, and diffusion effects. Our results show that experiments can become coordination infrastructures that temporarily bridge fragmented governance structures, enabling heterogeneous actors to build trust, co-produce knowledge, and adapt strategies through negotiation and iterative learning. These micro-level processes actively construct cross-system linkages, allowing local experiments to evolve into institutional arrangements that support regional low-carbon industrial diversification and economic upgrading. This study contributes to transition theory by grounding the micro-foundations of multi-system transitions and showing how experimentation can help overcome fragmented governance structures by enabling state-orchestrated coordination. • Local experiments drive multi-level system interactions and participant-driven reforms. • Simultaneous experimentation at niche and regime levels fosters system integration. • Cross-system learning facilitates multi-system innovation and policy diffusion. • Fragmented governance is alleviated through temporary collaboration models. • Economic viability and stakeholder cooperation are critical for sustained innovation.
Xie et al. (Wed,) studied this question.