Abstract: A system includes electrical equipment racks arranged in at least one row and including at least one electrical equipment rack having at least one UPS therein. The system further includes a bus duct assembly including an elongate housing extending along the at least one row and having electrical bus bars therein electrically coupled to the electrical equipment racks and including at least one AC bus bar coupled to an output of the at least one UPS and at least one DC bus bar coupled to an input of the at least one UPS. The bus duct assembly may further include at least one cooling air passage in communication with airspaces of the electrical equipment racks.