The purpose of this paper is to analyze the socio-economic dynamics that are brought about by renewable energy technologies. We call this dynamic "Social Innovation" as it changes the rules of risk-benefit distribution and the roles of social actors. For this purpose, we take up a typical case in Japan, community wind power in which the initial cost is funded by the investment of citizens. Through this case study, we examine how the citizens' initiative can affect the social acceptance of renewable energy as well as social change. Based on interviews with those involved in these projects, we analyze the interests of the various actors involved in community wind power projects in a framework of "actor network theory", which enables us to understand the detail of each actor's position. This study also involved a quantitative survey of investors. The case study clarified that there was a remarkable difference in the interests of the main actors in the community wind power projects, the networks are complex and actors share various interests such as economic interests and a sense of social commitment, participation and contribution. These incentives are also clarified in quantitative data. However, the variety of incentives differs in each project. (c) 2007 Elsevier Ltd. All rights reserved.