More wind energy projects could get a green light after the release of an overdue Dept. of Defense study about wind farms' effects on military radar. In a Sept. 27 report to Congress, DOD says it backs developing wind energy sources as long as they don't interfere with radar lines of sight. But critics note the study questions the effectiveness of efforts to mitigate potential radar conflicts and it calls for more research to improve mitigation.

The Federal Aviation Administra-tion must approve wind farms. It considers DOD concerns in its reviews. In June, the Sierra Club sued DOD for failing to finish the report by a May 8 deadline. The group argued that at least 15 wind projects were shut because of FAA concerns about radar conflicts. The American Wind Energy Association says FAA recently approved hundreds of wind farm applications.