Shrouds Can Be Useful in Wind Turbine Design

About once a month, I see a concept for a wind turbine that contemplates some sort of shroud to catch and funnel more wind through a turbine at higher speeds.  In principle, there is no problem with such ideas, other than, of course, the trade-off that is created by the cost of the materials and the room to site them.  Here’s a folksy article about an artistic shroud at a baseball field that has quadrupled the power output of the turbines.