Marie Axt forsvarer sin ph.d.-afhandling
Marie Axt forsvarer sin ph.d.-afhandling "Circular economy strategies for EU open strategic autonomy: The case of critical raw materials in European hydrogen technology value chains".
Forsvaret er offentligt, og alle er velkomne. Forsvaret er planlagt til at vare maksimalt tre timer og vil foregå på engelsk.
Ph.d.-skolen ved Institut for Samfundsvidenskab og Erhverv er vært ved en lille reception efterfølgende.
Vejledere og bedømmelse
Bedømmelsesudvalg:
- Helene Dyrhauge, Associate Professor, ISE, Roskilde University, Denmark (forperson)
- Rikke Dorothea Huulgaard, Associate Professor, Aalborg University, Denmark
- Dr. Heiner Schanz, Professor, University of Freiburg, Germany
Leder af forsvaret:
- Lena Brogaard, Associate Professor, ISE, Roskilde University
Ph.d.-vejledere:
- Hovedvejleder: Lars Buur, Professor, ISE, Roskilde University
- Bivejleder: Julian Kirchherr, Associate Professor, ISE, Roskilde University
- Bivejleder: Brian Baldassarre, Assistant Professor, Delft University of Technology and EU Commission Joint Research Centre
Resumé
This PhD thesis explores the potential of circular economy strategies to support the European hydrogen technology value chain within the context of European Union (EU) public policy. It is motivated by two parallel developments in European economic governance over the past decade. First, the circular economy has emerged as a central sustainability concept in both academic scholarship and policy-making and was formally adopted as an official EU policy doctrine in 2015. Originally promoted as a way to reconcile economic growth with environmental sustainability, the circular economy promises to reduce resource use, minimise waste and decouple prosperity from primary material extraction. Despite its prominence and conceptual appeal, however, empirical evidence shows that the actual adoption of circular practices remains limited, fragmented and uneven across sectors. This persistent gap between ambition and implementation has become a key concern in circular economy research.
Second, European policy discourse increasingly focuses on vulnerabilities associated with globalised value chains, particularly with respect to critical raw materials. Geopolitical tensions, supply chain disruptions and global competition for strategic resources have highlighted the risks associated with external dependencies. In response, the EU has articulated the concept of open strategic autonomy, which seeks to balance openness to global trade with the capacity to secure key technologies, materials and industrial capabilities domestically. Within this context, the circular economy has been advanced as a potential solution to critical raw material challenges by public institutions and practitioners. It is argued that strategies such as reuse, lifetime extension and recycling could reduce dependence on primary imports. This has been reflected in policy initiatives such as the Critical Raw Materials Act. Yet, while conceptually persuasive and proposed in practitioner circles, the contribution of circular economy strategies to strategic autonomy has largely remained hypothetical, and is empirically and conceptually underexplored in academia.
The central aim of this PhD is to bridge this gap by examining whether and how circular economy strategies can contribute to the EU’s open strategic autonomy in practice. It advocates broadening the applicability of the circular economy concept as an approach not only for reconciling economic growth with environmental sustainability, but also to consider it as an approach to address issues of resilience and autonomy. It does so through an in-depth case study
of the European hydrogen technology value chain. The overarching research question guiding the thesis is: Can circular economy strategies contribute to the open strategic autonomy of the European Union and, if so, what are the impeding and enabling factors? The research was conducted in collaboration with the European Commission’s Joint Research Centre in the wider context of the BounCE4ward project, a multi-year initiative investigating the role of circular economy strategies in addressing critical raw material challenges across different strategic value chains. Within this broader effort, this thesis contributes a detailed analysis of hydrogen technologies.
The hydrogen technology value chain was selected for several reasons. Green hydrogen is widely regarded as a key component of the EU’s decarbonisation strategy, particularly for hard-toabate sectors such as heavy industry and long-distance transport. At the same time, hydrogen technologies are classified as strategic assets due to their reliance on critical raw materials, especially platinum group metals. Throughout my research I focused on the specific technology of proton exchange membrane (PEM) electrolysers and fuel cells, which face acute material bottlenecks related to iridium and platinum. These bottlenecks are among the most severe constraints to large-scale deployment. Focusing on these technologies allows for an in-depth examination of circular economy strategies in a context where material scarcity is already shaping industrial and policy debates. While the analysis centres on PEM technologies, many insights are transferable to other hydrogen technologies, such as anion exchange membrane and solid oxide systems.
An additional motivation for selecting this case is that the hydrogen technology industry is still relatively young. As an emerging and rapidly growing sector, it is not yet fully locked into linear production and end-of-life models, which creates a structural window of opportunity to integrate circular strategies early on. From a research perspective, this offers a unique opportunity to study how circularity can be shaped proactively, rather than retrofitted into established industries. It also allows the thesis to make a practical contribution by engaging stakeholders at a stage when institutional arrangements, business models and regulatory frameworks are still evolving.
To address the overarching research question in a structured manner, the thesis is organised around three interrelated articles, each guided by a specific research question. The first article lays the empirical groundwork by mapping the European electrolyser and fuel cell value chain and identifying relevant circular economy strategies across different stages of production, use and end-of-life. Drawing on expert interviews, it analyses the drivers and barriers that shape the adoption of strategies such as material reduction, lifetime extension, reuse and recycling. The first research question asks: What drives or hinders the adoption of circular strategies in the European PEM electrolyser and fuel cell value chain? The findings show that especially strategies to reduce material loads, prolong electrolyser lifetimes, and recycling strategies are of high relevance. While technical feasibility and long-term economic considerations act as drivers, short-term cost pressures, regulatory uncertainty and limited coordination across actors present significant barriers. We highlight key policy recommendations to address these, including a ban on waste
exports containing platinum and iridium, setting a specific iridium recycling target, and setting dismantlability requirements for technical products.
Building on these insights, the second article shifts attention from individual barriers towards system-level coordination in an emerging industry ecosystem. It examines what actions are required from public and private sector stakeholders to establish circularity before linear practices become entrenched. Proposing the Circular Emergence framework, the article identifies key functions that need to be activated across the value chain. The second research question asks: What actions are required from private and public sector stakeholders to establish circularity in an emerging industry ecosystem? The analysis highlights the importance of early guidance, coordinated investment, infrastructure development and legitimacy building to support circular pathways. We propose a matrix of concrete steps across three phases for key value chain stakeholders to pursue.
The third article takes a more conceptual and policy-oriented perspective by examining how circular economy ambitions are embedded within EU governance frameworks for hydrogen technologies. Drawing on public policy values literature, it analyses how the policy goals of growth, sustainability and strategic autonomy are integrated within relevant policy acts, and what this implies for coherent industrial policy. The third research question asks: How are the different policy aims of growth, strategic autonomy and sustainability integrated within the policy acts that govern the hydrogen technology value chain and what are the consequences for the possibility of pursuing a coherent industrial policy framework? The findings reveal that while policy narratives emphasise value alignment, implementation often prioritises rapid scaling and competitiveness over circular design and end-of-life considerations, leading to latent tensions. On this basis, I argue for the consideration of tensions in the policy-making process, to better balance the different policy goals.
Across the three articles, the thesis provides a comprehensive mapping, analysis and discussion of circular economy strategies in the hydrogen technology value chain, an empirical account of what enables or constrains their adoption, and a stakeholder-informed analysis of how circular ecosystems can be developed in practice. By connecting circular economy research with industrial policy and policy values scholarship, the thesis contributes a novel perspective that
highlights the governance challenges of implementing circularity in strategic industries. I argue that circular economy strategies have significant potential to support the hydrogen technology value chain and enhance the EU’s open strategic autonomy and resource resilience more broadly. However, realising this potential is far from straightforward. It requires early, coordinated and coherent policy action that explicitly addresses trade-offs, sequencing and stakeholder responsibilities. Without such coordination, circular economy ambitions risk remaining aspirational rather than transformative. In conclusion, this case study thesis makes a strong argument to shift and broaden the concept of the circular economy as an approach that can reconcile different policy goals, including those of growth, sustainability and strategic autonomy, and therefore is of relevance beyond the realm of sustainability studies.
Afhandlingen vil være tilgængelig for læsning på Roskilde Universitetsbibliotek inden forsvaret (til brug på stedet). Afhandlingen vil også være tilgængelig ved forsvaret.