Rhythms animate our lives and the worlds we inhabit. Rhythms of getting things done, of working technologies, of day and night and the seasons, and of shared patterns of work, home-life and moving around. Rhythms are also intrinsically about flows of energy - heat, light, motion - from the smallest movements of muscles, to the petrol-fuelled rhythms of the rush hour, the spinning of wind turbines and shifting cycles of solar radiation. This book sets out to energise Lefebvre's rhythmanalysis in order to develop a novel and far reaching polyrhythmic conceptualisation of the beats and pulses of our relations with energy in both its natural and technological forms. Social theory, thermodynamic thinking and diverse streams of energy-oriented research are brought together to trace how the climate crisis has the rhythmic patterning of big power energy systems at its core; and how transitioning to a just, low carbon future means transforming energy systems and our everyday dependencies on them into new rhythmic patterns and interrelations.