Government policy and innovation activity : a patent study of solar photovoltaic balance of system in Japan



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This report studied innovation activity in four areas of the solar photovoltaic balance-of-system (BOS) technologies (inverters, mounting equipment, monitoring systems, and site assessment) in the Japanese market. Through patent searches with specific keywords, this study found that innovation activity in these four technology areas increased and decreased responding to both supply-side and demand-side policies. This report also empirically studied effects of demand-pull policies on innovation activity in the BOS technology areas. The regression analysis of the patent data found that the demand-side policies such as residential subsidy programs employed by the Japanese government were a major factor which influenced innovation activities in these technology areas in the Japanese market. Finally, the regression analysis also found that the termination of the residential subsidy program by the government in 2006 had a negative effect on the innovation activity of the four BOS technologies.