Delivering net zero by 2050 will require governments to utilise all available abatement opportunities, yet current policy largely ignores socially-driven mitigation in favour of technological innovation in the energy sector. Past energy transitions have typically taken several decades, but policymakers remain confident that low carbon technology can be deployed in time for a 2050 mitigation target. We consider the potential for social transitions to deliver emissions reductions within this time frame. Based on detailed analysis of 12 past transitions, we develop frameworks for technological and social transitions which draw out the relationships between progress, policy and diffusion. Using our generalised frameworks we compare the duration of transitions, finding that the technological transitions in our study take on average four decades longer than the social transitions to go from initial conception to market or behaviour saturation. Our evidence suggests that policymakers who continue to rely on technology transitions to reduce emissions will be unable to deliver climate targets by 2050. By engaging with the public to stimulate social transitions governments could have more impact, more swiftly. Only by utilising both technological and social transitions can policymakers hope to achieve net zero emissions by 2050.

到2050年实现净零排放将要求政府利用所有可用的减排机会，但是当前的政策在很大程度上忽略了社会驱动的减排，而支持能源行业的技术创新。过去的能源转型通常需要花费数十年的时间，但政策制定者仍然相信可以为实现2050年减排目标及时部署低碳技术。我们考虑了在这一时间范围内实现社会转型以实现减排的潜力。在对过去12个过渡的详细分析的基础上，我们开发了技术和社会过渡的框架，这些框架确定了进步，政策与扩散之间的关系。使用我们的通用框架，我们比较了过渡的持续时间，发现从最初的概念到市场或行为饱和，我们研究中的技术转型平均比社会转型要花费四十年的时间。我们的证据表明，继续依靠技术转型来减少排放的政策制定者将无法在2050年之前实现气候目标。通过与公众互动来刺激社会转型，政府可以更快地产生更大的影响。决策者们只有利用技术和社会转型，才能希望到2050年实现净零排放。通过与公众互动来刺激社会转型，政府可以更快地产生更大的影响。决策者们只有利用技术和社会转型，才能希望到2050年实现净零排放。通过与公众互动来刺激社会转型，政府可以更快地产生更大的影响。决策者们只有利用技术和社会转型，才能希望到2050年实现净零排放。