The rise of phase-out as a critical decarbonisation approach: a systematic review

Abstract

‘Phase-out’ is increasingly mobilised in research and policymaking as an approach to catalyse the gradual decline of technologies, substances and practices that compromise environmental sustainability objectives. This trend is particularly pronounced in the context of climate change, demonstrated by the accumulation of a vast body of scholarship over multiple decades. Our work provides the first systematic review of the state of this knowledge, mapping out how phase-out is studied and employed as a policy tool for mitigating climate change. We systematically review over 400 publications, spanning three decades (1990-2021) and diverse scientific fields. Our review asks: How has scholarly work discussed phase-out as an approach to mitigate climate change, and how has this changed over time? We tackle this question from five perspectives: (i) elements targeted by phase-outs, (ii) policy instruments, (iii) affected industries, (iv) geographic context, and (v) benefits besides climate change mitigation. Results reveal that phase-out has widely proliferated as a decarbonisation approach, developing into a bridging concept that links diverse communities of contemporary science and practice. This is reflected by engagement with manifold phase-out targets – stretching well beyond the usual suspects related to fossil fuels and end-use technologies – as well as discussion of a growing diversity of industries, policy instruments and geographies in the literature. This global proliferation of phase-outs is propelled by expectations of diverse co-benefits. Aside from gains for the environment, economy, society and health, we find widespread acknowledgment that phase-out can drive innovation and systemic change beyond mere substitution. Our study also identifies several underdeveloped and underrepresented directions meriting further study. These notably include phase-out activity beyond Europe, North America and China, hard-to-abate industry sectors and non-fossil fuel targets. We conclude by carving out broader implications for scholars and practitioners to inform future research directions and climate mitigation efforts.

Public preferences for phasing-out fossil fuels in the german building and transport sectors

“…These determinants likely explain why packaging different sets of policy instruments also shows higher public support when packages include supportive measures (Bergquist et al 2020, Wicki et al 2020. While there has been a rising number of studies focussing on phase-outs, 'there is an additional need to further elucidate the conditions that enable or prevent the introduction and smooth implementation of phase-out policies' (Trencher et al 2022). Indeed, only a few studies have assessed public preferences for phase-out policies.…”

“…For both sectors, we explore preferences with respect to phase-out date, the choice of economic and regulatory policy instruments including taxes and bans on technology purchase and use, and the supplementing of these with support instruments including loans and subsidies. Vis a vis distinct types of phase-out instruments as suggested for example by Trencher et al (2022), this selection covers management and planning, economic, command and control, as well as capacity building policy instruments. The selected policies are salient to current policy proposals at the EU and national levels and could be effective in achieving a full phase-out.…”

Ten new insights in climate science 2023

“…A managed approach is needed, which entails preventing new facilities being built (IEA, 2023c), establishing timelines for phasing-out existing facilities (Trencher et al, 2022), creating financial mechanisms for an orderly wind-down (GFANZ, 2022), coordinating actions on fossil fuel supply and demand to avoid price volatility (Diluiso et al, 2021), ensuring a just transition for workers and communities, and fairly allocating efforts between countries (Muttitt & Kartha, 2020).…”

“…Many national-level efforts are addressing gasoline vehicles and fossil-gas heating systems in buildings (Kerr & Winskel, 2022). In sectors lacking viable alternatives (steel, cement, aviation, shipping), there is less phase-out research and policy (Trencher et al, 2022). Efforts to reduce fossil fuel consumption in military operations, which are a major source of publicly financed emissions globally, also lag (Stoddard et al, 2021).…”

A Divestment Model: Migration to Green Energy Investment Portfolio Concept

“…"Phase-down" is herein defined as the gradual elimination of an act of production at different stages of a process. Trencher et al [2] have reviewed the decarbonization approach and have made recommendations towards advancing Sustainable Development Goals (SDGs) 12 and 13 [3]. Their study pointed out that the approach towards achieving the net-zero GHG should be multi-disciplinary, and that due care must be taken to understand how each country will be impacted by this drastic change.…”