When is it feasible for policies to accelerate energy transitions? The case of REPowerEU

To mitigate climate change, transition to clean energy should proceed faster than in the last three decades. Can policies overcome economic, technological and social inertia to achieve the required acceleration, and if so, under what conditions? The 2022 REPowerEU plan is an excellent case to investigate these questions because it responds to a profound energy security threat (Russia’s invasion of Ukraine) in advanced economies that are already the global leaders in decarbonisation. Here we analyse to which extent REPowerEU and related policies aim to accelerate energy transitions, what has enabled the ambitious targets, and whether these are feasible. Considering policy-technology co-evolution involving multiple feedbacks and non-linear growth, we define policy-driven acceleration as a significant deviation of feasible policy goals from the S-curve of technology diffusion reflecting empirical trends, near-term projections and analogies. We show that REPowerEU sets unprecedented targets implying acceleration of all renewables and a radical deviation from the onshore wind growth trajectory. At the same time, REPowerEU is not an isolated crisis response, but a continuation of a policy shift that started around 2018 and included the European Green Deal (2019), the ‘Fit for 55’ package (2021), and related plans. Before 2018, policy targets extended historical trends and did not become more ambitious over time. Although motivated by climate concerns, they were only weakly linked to long-term climate goals but strongly shaped by technological uncertainties and economic costs. Energy security was seen as protection from short-term shocks through resilient infrastructure and did not directly shape the goals for renewables. In contrast, post-2018 policies decisively link the net-zero vision for 2050 and the 2030 renewable targets. In 2022, these climate-derived targets were securitised through directly linking them to energy independence from Russian oil and gas, now viewed as a long-term security concern. Both net-zero and energy independence goals were inspired by the declining costs of renewables and by the emerging technological opportunities of substituting fossil fuels in transport, industry and heating through low-carbon electrification. We analyse whether the new targets are feasible using the ‘inside’ and the ‘outside’ view of feasibility by Jewell and Cherp (2023). We argue that the main barriers for onshore wind are conflicting land uses, for offshore wind - uncertainties around the infrastructure and complementary technologies, and for solar power - grid integration. We show that the required growth of each renewable technology is similar to the growth of nuclear in Western Europe in the 1960s-1980s. The similarities between the two contexts, including the presence of an energy security crisis, give hope that the planned growth is feasible. However, the combined growth of solar and wind is entirely unprecedented, although on a smaller scale, a similarly fast growth of nuclear occurred in France and Sweden. Our findings indicate that policy-driven acceleration of energy transitions might be possible but requires a unique constellation of motivations and capacities. Historical analogies provide useful benchmarks for the attainable speed of transition, but more research is needed on the applicability of policy lessons across different low-carbon technologies.