KEYWORDS: organic energy system, energy history, Sweden, firewood.JEL CODES: N00, N53, N72, N73.T his article discusses the historical conversion of the Swedish organic energy system into a mineral one. The main argument is that there was a dynamic interaction between the two systems during the Swedish industrialization process. For one, growth of the mineral energy system contributed to open previously inaccessible organic resources in the forests of northern Sweden. Secondly, the development of the pulp and paper industry contributed to the switch from charcoal to coke in the iron manufacturing industry. Thirdly, the development of hydropower, itself an organic source of energy, further contributed to the emergence of a mixed energy system. One can therefore perceive the Swedish transition from an organic to a mineral energy system as a shift from a traditional organic energy system to an industrialized one, that is, an organic energy system dependent on the technologies and organizational structures of the mineral energy system in order to function.