Sociology has largely ignored the contribution of the German Nobel-Prize-winning chemist Wilhelm Ostwald to the sociology of energy, mainly due to Max Weber’s (1909) dismissive reception of Ostwald’s ‘energetical thought’. This article reclaims Ostwald’s significance for contemporary sociology, through a translation and exposition of ‘Sociological Energetics’, first published in 1908 as the final chapter of a popular book on energy. Ostwald’s deliberations, which derive from his engagement in contemporary debates on thermodynamics and energetics, brought him into contact with classical sociologists, including Rudolf Goldscheid, Georg Simmel, Ferdinand Tönnies and Weber. Ostwald’s contribution to sociology lies in his focus on the cultural significance of energy relations and transformations. In their encounters with Ostwald and energetics, Simmel, Tönnies and Weber all reveal the potential importance of Ostwald’s work on energy relations in thinking productively about the relationship between technology and culture.