The technologies needed to decarbonize the electricity system are already commercially available. There are mathematical models of how these technologies can be deployed sufficiently fast and at a large enough scale to displace fossil fuels to meet climate targets. Yet there is no scientific method to evaluate whether these scenarios are feasible given the real world’s socio-political constraints. MANIFEST develops a new scientific understanding of socio-political feasibility of climate change mitigation that takes into account the context, actors and change over time. Theoretically, MANIFEST combines a definition of socio-political feasibility from political philosophy with the concept of causal mechanisms of energy transitions. Thus, I shift the thinking about the feasibility of climate change mitigation from its current focus on barriers and enablers to a dynamic and context sensitive view with space for actors and agency. Empirically, I focus on transitions in electricity supply including the expansion of low-carbon electricity and coal phase-out. I explore three areas which are critical for the feasibility of decarbonisation of electricity: (i) the role and capacities of international suppliers of electricity technologies, (ii) the competition between electricity technologies at the early stages of their introduction in emerging economies, and (iii) factors shaping the growth of low-carbon technologies and under what conditions they substitute carbon-intensive ones. Methodologically, I develop a new approach to assess the feasibility of climate solutions by constructing dynamic feasibility spaces which are a function of paths, contexts and actors. I test this approach by analysing national low-carbon electricity targets to determine whether states plan to accelerate decarbonisation beyond the current feasibility frontier. This dynamic feasibility space is a breakthrough in assessing the feasibility of national and global climate change mitigation solutions.