A company called Devecitech has just created what it calls the 'ENLIL' vertical axis wind turbine, that sits at the side of a highway generating electricity from the wind-power created by passing cars
Video here: http://devecitech.com/
My question is: does the presence of this turbine 'steal' energy ('negligible' or otherwise) from passing cars by creating drag where there would otherwise be free space?
If so, will it only ever generate less energy than it 'steals' from the passing cars?
Or is it purely harnessing energy that would otherwise be wasted?