ESL200 electric louvers for the building with energy-saving requirements are very good choice.  It is mainly used for daily ventilation  and  smoke-exhaust of the building.  It can be controlled by linkage with electromechanical equipment, and the louvers are opened when the equipment is running and closed when the equipment is stopped.  It can achieve the maximum energy-saving effect when it is closed, and the opening angle can be customized.