The document reviews the diffusion of clean technologies and proposes suggestions for future diffusion analysis. It discusses several stylized facts about technology adoption, including that adoption is not instantaneous, the diffusion of one innovation affects others, and that diffusion involves information transfer but is not solely based on information. It also notes that economic attractiveness increases adoption rates but does not guarantee immediate adoption. The document concludes by discussing soft innovations, the age of industrial plants, regulatory pressure, and proposes new econometric methods for analyzing diffusion.