improved means for powering and increasing evaporative cooling in an indirect - direct evaporative cooling apparatus are disclosed . sustainable energy from solar energy mixed with grid power , when needed , power the idec device . these dc and ac power sources are seamlessly merged in a unique diode interconnect unit . improved means for evaporative cooling include a rayon - based flocking on the wet side of molded plastic indirect evaporative cooling plates . separate wet and dry passages through those plates are facilitated by a unique means for clamping the upper ends of the plates . these clamping means also add to the structural integrity of an array of plates so that the array can be inserted in and removed from a housing containing other operational components of the idec such as fan , direct cooling plates and water distribution means . applicants idec utilizes improved porous piping that allows uniform and continuous distribution of water to all wet passages within both the indirect and direct stages of the idec . operational controls for the system limit the potential water damage caused by overflow of water from the idec housing .