The diffusion of energy technologies. Evidence from renewable, fossil, and nuclear energy patents

Technology innovation is widely recognised as a critical means in tackling climate change and fulfilling energy policy objectives. The objective of this paper is twofold: first, to provide a descriptive analysis of innovation in energy technology across countries and sectors and over time; and second, to explore the determining factors of patented knowledge diffusion of energy technologies by distinguishing between renewables and other energy patents, i.e., fossil and nuclear patents) thorough a regression analysis. The data employed in this paper consists of an original database on renewables and other energy patents applied by firms in the period 1990-2015 and contained in PATSTAT. By drawing on patent citations as an indicator of knowledge diffusion and focusing on characteristics extracted from patent documents, a set of econometric models is estimated. Our results show that those patents containing more citations to previous scientific literature and patents attain greater diffusion. Joint patents with other firms or universities exert a negligible effect on technology regarding renewables. Co-ownership with universities has a negative effect on the diffusion of other types of energy technology. Several policy implications can be determined from our results: for example, the justification for policies oriented towards enhancing the incorporation of scientific knowledge and co-inventorship in energy innovation.