Knowledge sources and impacts on subsequent inventions: Do green technologies differ from non-green ones?

The paper contributes to our understanding of the nature and impact of green technological change. We focus on the search and impact spaces of green inventions, scrutinising the knowledge recombination processes leading to the generation of the invention and the impact of the invention on subsequent technological developments. Using a large sample of patents filed during 1980-2012, we analyse a set of established patent indicators that capture different aspects of the invention process. Technological heterogeneity is controlled for by comparing green and non-green technologies within similar narrow technological domains. Green technologies are found to be more complex and radical than non-green ones and to have a larger and more pervasive impact on subsequent inventions. However, the results show a variety of distinctive patterns with respect to the knowledge dimension considered. We derive some important policy implications.