The emergence of a field of global energy policy is usually traced back to the events around the 1973–74 oil embargo. This article provides a prehistory to this by tracing the genealogy of the ‘global energy economy’. This genealogy is reconstructed through the lens of the World Power Conference (WPC, today the World Energy Council, WEC), a non-governmental international organization founded by a British electro-technical engineer in 1924. In a comparison with the engineering of ‘natural forces’ in the nineteenth-century steam economy, I argue that electricity, and particularly large electrical systems, not only changed the meaning of power and institutionalized a regular documentation of the ‘power economy’, but enabled and concentrated ownership of the ‘forces of nature’ as a productive factor. This more comprehensive view of the role of electricity in the economy gave rise to an energo-materialist economics among the electro-technical engineers, technicians, and planners whom the WPC assembled. The WPC imagined itself as the centre of calculation of this ‘global energy economy’, initiating international standardization and complementing the statistics of international organizations such as the League of Nations and the United Nations. As the integration of all ‘energies’ in one statistical model required conversion factors across very different technical processes, it took the urgency of the oil crisis for the WEC to compile a global energy balance, thus statistically ‘representing’ the state of the ‘global energy economy’.