This paper investigates the speed of adoption of energy technologies in a traditionally innovation importing country, Portugal, as compared with countries where these technologies first started. Data were collected on the growth of eight energy-related technologies, both energy supply (e.g. natural gas plants, wind turbines) and end-use (e.g., motorcycles). The analysis is done in terms of the evolution of the number of units and installed capacity, indicating possible scale effects. The results show an average adoption lag of one to two decades relatively to “Core” countries. However, the growth rate increases when a technology arrives at Portugal, confirming the hypothesis that adoption accelerates when technology reaches new markets. Additionally, the duration of diffusion in Portugal is less constrained by the final scale of diffusion, contrasting with previous observations for the Core. The data also uncover the successful diffusion of wind energy in Portugal, showing that growth took off less than a decade after the diffusion in the Core, and achieving similar levels of intensity. The analysis suggests that this was supported by the improvement in the adoption capacity, associated with the development of a wind energy innovation system. These findings open new perspectives for the spatial diffusion of sustainable innovations
