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

The paper investigates the nature and impact of green technological change. We focus on the search and impact spaces of green inventions: we explore the knowledge recombination processes leading to the generation of inventions and their impact on subsequent technological developments. Using a large sample of patents, filed during the period 1980-2012, we employ established patent indicators to capture the complexity, novelty and impact of the invention process. Technological heterogeneity is controlled for by comparing green and non-green technologies within narrow technological domains. We find that green technologies are more complex and appear to be more novel than non-green technologies. In addition, they have a larger and more pervasive impact on subsequent inventions. The larger spillovers of green technologies are explained only partially by novelty and complexity.