Sounds expensive and intermittent: Wind farm's radar system stops birds getting the chop | World news | The Guardian

The installation, which opened late last month, uses radar systems originally developed for Nasa and the US air force to detect approaching birds from as far as four miles away, analyse weather conditions, and then determine whether they are in danger of flying into the rotating blades.

If they are, the turbines are programmed to shut down, restarting once the birds are safely on their way, said Gary Andrews, the chairman of DeTect Inc, the Florida company which developed the technology. The system spots the birds and assesses their altitude, numbers and the visibility. "With all these pieces coming together properly … the turbines will shut down," said Andrews.