The politics of policy-mix-making processes in sustainability transitions: exploring the failure of the Zero Carbon Homes policy mix in the UK

Understanding the politics and policymaking processes in sustainability transitions remains a crucially important challenge (Köhler et al., 2019). A number of recent contributions in the sustainability transitions literature have started to explore these themes, drawing from various disciplines and approaches. These include theories of the policy process (for a review Kern & Rogge, 2017); power relations and agency (Flor Avelino, 2011) and institutional literatures (Andrews-Speed, 2016; Lockwood, Kuzemko, Mitchell, & Hoggett, 2017). Authors have pointed to insights which are useful for conceptualising certain aspects of the overarching multi-faceted processes of policymaking, but there is less attention to linking these ideas or approaches to processes of socio-technical change in a co-evolutionary manner. Developing such a co-evolutionary perspective can help better explain policy outputs as a result of socio-technical change, and how these outputs then stimulate subsequent sociotechnical change. Understanding this dynamic relationship can also help explain policy change or stability over time. Perhaps more importantly, many of the aforementioned contributions have only focussed on single policy instruments and their revisions over time. However, due to the scale, complexity and urgency of sustainability transitions, scholars and practitioners have increasingly recognised the need to implement combinations of multiple policy instruments, coordinated to meet an overall transition strategy (Rogge, Kern, & Howlett, 2017). Accordingly, the policymaking processes for such ‘policy mixes’ are more complex, and both their design and analysis are more challenging. However, despite several calls for more attention to processes underpinning the development of policy mixes over time, there remains little substantive conceptual development. While it is beyond the scope of a single doctoral thesis to synthesise the aforementioned multitude of insights, ideas and approaches related to policy-mix-making processes, the thesis takes a step forward in this regard. It links policymaking processes, socio-technical change, and political and policymaking institutions, to better conceptualise the development of policy mixes aimed at fostering socio-technical change towards sustainability. The thesis first develops (paper 1) and applies (paper 2) a co-evolutionary framework to conceptualise interactions of policy-mix-change and socio-technical change over time. The framework is mostly endogenously orientated in its explanation of change, drawing ideas from policy feedback theory. The central focus is how policy design choices alter actor behaviour to induce change in the socio-technical system, and generate incentives for actors to participate in subsequent policymaking. The core idea of policy feedback is that new policy can stimulate change in ways which helps stabilise it (making it increasingly locked-in over time), or which undermine it. The thesis then turns to institutional literature (paper 3) to help explain how the interests of actors are translated into policy outputs by paying attention to the institutional structure in which the policymaking process plays out. While this approach also contains endogenous elements, it also looks exogenously at the influence of political and policymaking institutional arrangements to analyse their influence on decision-making and policy outputs. The thesis utilises these analytical approaches to help explain the failed transition of domestic housing in the UK, specifically focussing on the Zero Carbon Homes policy mix between 2006 and 2016. The analysis of a failed attempt of a transition not only generates case-specific insights, but also helps identify more generic implications for policymaking about negative dynamics and makes recommendations to avoid their reoccurrence. Paper 2 generate insights about: i) how a virtuous cycle can be offset, and how this could be avoided; ii) what limitations may prevent a policy mix from producing more positive feedback; and iii) how perceptions of policy mix credibility are formed and how these affect socio-technical change. Paper 3 builds upon these insights, paying attention to institutional factors which may limit positive feedbacks and affect policy mix credibility. The main contributions of the thesis are that it develops a novel co-evolutionary framework (paper 1), produces novel insights by applying this empirically (paper 2), before zooming-in on the policy subsystem and developing three heuristic forms of institutional arrangements which contributed to the failure of the zero carbon homes policy mix (paper 3). The thesis therefore links policy design literatures with policy-process theory and political science. By linking these more explicitly, it makes a contribution to the literature on the politics of transitions by generating insights about the influence of politics in policy-mix-making processes and the co-evolutionary relationship with socio-technical change. Ultimately, the thesis derives insights which may help practitioners and analysts make more informed policy design choices by ‘thinking-through’ the potential implications of policy-mix-making decisions. Accordingly, this may enable them to make choices which are not only more likely to achieve their respective policy objectives, but may also help to maintain political support over time.