Knowledge spillovers from green technologies

This paper analyses and compares the morphology of knowledge spillover networks based on green versus non-green technologies to assess whether one of the two domains diffuses more widely, travels farther in the geographical space, and connects more extensively otherwise distant technological fields. We employ various metrics based on forward citations to measure knowledge spillovers from patented technologies. Our sample includes bibliometric data of 3,809,214 patent applications filed at the European Patent Office from 1981 to 2020, of which 316,897 (8.32%) are classified as green. Results show that green patents receive more citations – both directly and indirectly – from follow-on inventions than non-green ones, thus contributing to a greater knowledge diffusion throughout the entire spillover network. We also find that the spectrum of sectors to which a green knowledge spillover network is targeted tends to be broader. Lastly, the inherent nature of green technologies, along with their potential to act as boundary spanners, results in knowledge transmission within the green do-main being less geographically localized than for non-green technologies.