Wind energy infrastructure being installed across Japan was found interfering with Self-Defense Forces radars for detecting missiles, prompting the Defense Ministry to call for changes in some projects, multiple sources related to the matter say.
In some instances, the ministry also called for such infrastructure not to be installed in areas that had been singled out by the government as favorable locations for offshore wind power generation, the sources said.
The government is now considering reviewing rules governing wind power installations.
While the ministry has not disclosed specific cases, more than 10 locations, including some offshore ones, have become subject to project changes or investigations, with some energy operators being asked to revise their projects, according to the sources.
However, no legislation exists that allows defensive needs to be used as grounds for restricting infrastructure from being built on the land.
That has left one government official commenting that the situation could be a “defect” undermining national security.
According to the ministry, SDF radars emit radio waves that reflect off objects, with the returning signal allowing those objects to be located.
But large wind turbines sometimes block the radio waves or create larger reflected signals, making those reflected off objects like missiles and planes more difficult to detect.
Onshore wind power facilities are mostly located along coastlines or in mountainous areas, with some of them within the detection range of SDF radars, according to the sources.