A variety of offshore power generation installations have been set in many countries. In the offing of Fukushima, one offshore floating transformer substation and three offshore floating wind turbines have been set as an empirical study to realize the world’s first Wind Farm. However, some effects on ship traffic have been concerned due to installation and collision between ships and installations might occur. In order to maintain and improve navigational safety, it is important to understand collision risks around the installations. In this paper, authors analyzed navigation conditions around the installations by AIS data to consider navigation safety. Also, collision frequencies to the installations were calculated as an index of collision risk based on the analysis of the ship traffic, and consider risks and effects caused by Wind Farm. It is found that there were collision risks because ships navigated near the installations, so that another safety measures may be needed.
