Available open access digitally under CC-BY licence. Portugal is among the best-placed European countries to take advantage of solar power, having achieved a five-fold increase in installed capacity during 2017-2023 despite financial constraints.In 2023, its National Energy and Climate Plan set an ambitious target for a further eight-fold increase from 2.5 GW to 20.4 GW by 2030. How can such fast-paced deployment secure sociospatial justice?What insights do political economic dynamics hold for future transitions?Drawing on long-term, multi-sited ethnographic fieldwork, this book is a one-stop resource for policy makers, practitioners, scholars, and anyone interested in just solar energy transitions. Siddharth Sareen won the 2024 Nils Klim Prize, recognising his exemplary work in the search for renewable and sustainable sources of energy.